List of media notable for being in development hell

This article lists notable examples of media projects, including films, music, and video games, that were or have been in development for at least ten years after their first public announcement before release without being officially cancelled, a state known as "development hell", or, in the software industry, vaporware.

Films

 * 1906: A film based on the 2004 historical novel was planned as early as when author James Dalessandro was researching 1906 as a prequel to his novel Bohemian Heart and he made a 38-page outline and six chapters of his novel when he found out the success of Titanic. Warner Bros. Pictures had the script sold despite other companies entering in a bidding war. Due to the big budget, Warner Bros. partnered up with Walt Disney Pictures and Pixar and it would have been the first time Pixar has been involved in a live-action film and the first time Pixar collaborated with a major production company other than Disney with Brad Bird directing though eventually he left the project due to working on Ratatouille. Warner Bros. reserved all sound-studios available on their Burbank lot for production. However, later that spring, Warner Bros. quietly released the reservations while Brad Bird continued rewriting the screenplay in order to lessen the massive scope of the story. In 2011, it was reported by Brad Bird that the film project was still being developed. The issues he raised was his difficulty in narrowing the scope of such a manner as to be true to the story within the constraints of practical film length. In February 2012, it was revealed that a rewrite of Dalessandro's script had been completed by Michael Hirst, and Brad Bird was now rewriting it yet again. In June 2018, Bird mentioned the possibility of adapting the book as a TV series and the earthquake sequence as a live-action film.
 * Akira: Warner Bros. acquired the rights to make a live-action American adaptation of the anime film and its manga of the same name in 2002, and have made a number of attempts to film it. Directors attached to the project since 2002 have included James Cameron, Stephen Norrington, Ruairí Robinson, the Hughes brothers, George Miller, Christopher Nolan, and Jaume Collet-Serra. It was announced in 2019 that filming would be done later that year, in a production produced by Andrew Lazar and Leonardo DiCaprio and directed by Taika Waititi. However, in August of that year, Waititi began work on the Marvel Studios film Thor: Love and Thunder, which once again put filming plans on hold.
 * Alien vs. Predator: Alien vs. Predator was first planned shortly after the 1990 release of Predator 2, to be released sometime in 1993. The production stalled for more than a decade, with frequent actor changes, restarts, and failed promotions of the film until its eventual release in 2004.
 * Alita: Battle Angel: James Cameron's live-action adaptation of Yukito Kishiro's manga series Battle Angel Alita was in development hell starting in the early 2000s. The project was finally completed under the direction of Robert Rodriguez and released in 2019.
 * American McGee's Alice: A film adaptation based on the dark fantasy video game that is loosely based on Lewis Carroll's Alice's Adventures in Wonderland was in development prior to the game's release. The crew at Dimension Films were shown footage of the game and were impressed with the visuals. Miramax head, Bob Weinstein supported the film adaptation. On July 5, 2000, FGN Online published an exclusive piece claiming that Electronic Arts had signed an agreement with Miramax to create a film based on the game with American McGee involved in the film's production. Wes Craven and John August were attached as director and screenwriter, with McGee co-producing the film alongside Collision Entertainment, and Abandon Entertainment acting as international distributor. No actors had yet been signed on, but Natalie Portman, Milla Jovovich, and Christina Ricci were rumored to be attached. Later on, the film was confirmed to be computer animated with a release date of 2003. On March 4, 2004, McGee reported that the project had moved from Dimension Films to 20th Century Fox. On June 21, 2005, The Hollywood Reporter claimed that Universal Pictures had acquired the film and signed Sarah Michelle Gellar on for the lead role with Marcus Nispel attached to direct. Rumors suggested that Jane March was going to be cast as the Queen of Hearts but it was denied. In 2013, McGee wanted to buy back the film rights through Kickstarter. Since 2015, however, McGee said that the feature film had gone on a hiatus.
 * Atlas Shrugged: Film and later television adaptations of Ayn Rand's novel were in development hell for nearly 40 years before the novel was adapted as the first part of a trilogy in 2011. Part II appeared in 2012, and Part III was released in September 2014, but with three different actresses playing female lead character Dagny Taggart in each part.
 * At the Mountains of Madness: Since 2006, Guillermo del Toro and Matthew Robbins wrote a screenplay based on H. P. Lovecraft's story but had trouble getting Warner Bros. to finance the project because Del Toro claimed that the studio was very nervous about the cost and it not having a love story or a happy ending (either of which is impossible to do in a Lovecraft story). In 2010, it was announced to be a 3D film and James Cameron would be a producer while Tom Cruise would star in the film. It was reported that Universal Pictures refused to green light the project due to del Toro wanting an R rating while the heads at Universal wanted a PG-13 rating. Later on, the film was pitched to Netflix after signing a multi-year deal with the streaming service in 2020. The script was rewritten to make it a smaller, weirder, and more esoteric version in respect of the scenes that he has left out before. Del Toro later stated that Tom Cruise feels too old to star in the film. Del Toro also stated that the film could be a stop-motion film.
 * Atuk: A film adaptation of the novel The Incomparable Atuk. Norman Jewison first purchased the film rights in 1971, and since then there have been several attempts to produce it. One Hollywood legend holds that the project is cursed because of the premature deaths of various actors who expressed an interest in the lead role: John Belushi, Sam Kinison, John Candy, Phil Hartman and Chris Farley.
 * Untitled fourth Austin Powers film: Since 2005, plans for a fourth film of the Austin Powers series were in discussion but has not been announced since then despite various updates as years went on.
 * Avatar: The Way of Water: The film was first announced in 2010, aiming for a release by 2014. The timeline has been pushed back a total of 8 times, due to director James Cameron being occupied with other projects, the VFX (visual effects) team working on creating underwater motion capture, and the COVID-19 pandemic affecting production. However, the film was released on December 16, 2022, almost a decade after initial development began, with other sequels in development.
 * Bajirao Mastani: The film was conceived in the 1990s and was finally announced in 2003 but was shelved indefinitely owing to its ever-changing cast. The film was finally revived in 2014 and went immediately in production and was released in December 2015.
 * Barbie: The idea of a live-action Barbie film had been in development at Cannon Films in the mid-1980s; little is known about it, other than a promotional blurb (with the plotline centering around Barbie showing her owner how all her dreams could come true), and it is unclear how far into development it got before Mattel ceased working with Cannon, following Cannon's live-action adaptation of Masters of the Universe (1987) flopping at the box-office. Development on a film based on the Barbie toy line began in September 2009, when it was announced that Mattel had signed a partnership to develop the project with Universal Pictures and with Laurence Mark as producer, but nothing came to fruition. In April 2014, Mattel teamed with Sony Pictures to produce the film, which would have Jenny Bicks writing the screenplay and Laurie MacDonald and Walter F. Parkes producing through the Parkes+MacDonald Image Nation banner they created. Filming at the time was anticipated to begin by the end of the year. In March 2015, Diablo Cody was brought onto the project to rewrite the screenplay, and Amy Pascal joined the producing team. Sony would again have rewrites done to the screenplay later that year, hiring Lindsey Beer, Bert V. Royal, and Hillary Winston to write separate drafts. In December 2016, Amy Schumer entered negotiations to star in the title role with Winston's screenplay; Schumer helped rewrite the script with her sister, Kim Caramele. In March 2017, Schumer exited negotiations, blaming scheduling conflicts with the planned June 2017 filming start; in 2023 she revealed she left the project due to creative differences with the film's producers at the time. That July, Anne Hathaway was under consideration for the title role, with Sony hiring Olivia Milch to rewrite the screenplay and approaching Alethea Jones to direct as a means to interest Hathaway into signing on. Jones was attached to direct until the rights were transferred to Warner Bros. Pictures in October 2018.  Margot Robbie was cast as the lead in 2019, after Gal Gadot turned down the role due to scheduling conflicts, and Greta Gerwig was announced as co-writer with Noah Baumbach before being confirmed as director in 2021.  The film was released on July 21, 2023, and it, alongside Oppenheimer, was a major commercial success.
 * Beetlejuice Beetlejuice: In 1990, Tim Burton commissioned a sequel to Beetlejuice called Beetlejuice Goes Hawaiian, written by Jonathan Gems. After multiple studio rewrites, in 1997 Gems stated that the film will never be made. In 2011, Warner Bros. hired Seth Grahame-Smith to write and produce a sequel. In 2013, Winona Ryder expressed her interest in the sequel saying, "I'm kind of sworn to secrecy but it sounds like it might be happening. It's 27 years later." In January 2015, writer Grahame-Smith said the script was finished and that he and Burton intended to start filming by the end of the year, and that both Keaton and Ryder would return in their respective roles. In April 2019, Warner Bros. stated the sequel had been shelved; however, in February 2022, a sequel was announced, produced by Plan B Entertainment with Warner Bros. Pictures. Brad Pitt will serve as a producer, while Keaton and Ryder will reprise their respective roles. Principal photography began in May 2023, for an intended release date of September 6, 2024.
 * Beverly Hills Cop: Axel F: Since the mid-1990s, the 4th film to the Beverly Hills Cop franchise was being developed yet it was finally given the release date of 2024 via Netflix due to limbo.
 * Bill & Ted Face the Music: An attempt to revive Bill & Ted came to fruition in August 2010 when franchise star Keanu Reeves indicated that a script for a third film was being worked on despite the fact that the character Rufus would not return, because the character's original actor, George Carlin, had died two years prior.  Dean Parisot was attached to direct by August 2012. In March 2013 at the SXSW Film Festival, Alex Winter confirmed progress on the film was still being made.  In April 2016, Winter told Forbes that they had a script, a director, and a studio, and that they were planning to film by early 2017. Reeves gave an update on the film in February 2017 during an interview on The Graham Norton Show, saying the story was written, and discussing the plot of the film: "Basically, they're supposed to write a song to save the world, and they haven't done that. The pressure of having to save the world, their marriages are falling apart, their kids are kind of mad at them, and then someone comes from the future and tells them if they don't write the song it's just not the world, it's the universe. So they have to save the universe because time is breaking apart". During the New York City Comic Convention, Reeves revealed that the title would be Bill & Ted Face the Music. The film was released on August 28, 2020.
 * BioShock: In 2008, it was announced that a film based on the 2K Games video game series was in development and Gore Verbinski got attached to direct yet it was cancelled due to budget concerns and executives not wanting to green lit an R-Rated story due to the failure of the Watchmen film. In 2020, Netflix announced a new BioShock film is in development with Francis Lawrence directing.
 * The Black Cauldron: Walt Disney Productions optioned Lloyd Alexander's five-volume book series in 1971, acquired the rights to Alexander's novels The Chronicles of Prydain, and began development of the movie in 1973. The release date was delayed several times. In July 1978, the studio pushed back the release date to Christmas 1984 due to their inability to animate realistic human characters, which caused The Fox and the Hound to be released in 1981. Re-production of The Black Cauldron began in 1980. Shortly before the film's initially planned 1984 theatrical release, a test screening of the rough cut of the film was held at the studio, but was met with negative feedback that claimed it was too intense and disturbing for the majority of the children in the audience, particularly during the climactic 'Cauldron Born' sequence. The newly appointed Disney studio chairman Jeffrey Katzenberg ordered certain scenes to be removed to calm things down. When producer Joe Hale objected to Katzenberg's demands, Katzenberg responded by taking the film and editing it himself. After Michael Eisner heard from Hale what Katzenberg was doing, he called him in the edit room and convinced him to stop. Though he did what Eisner told him, he requested that the movie should be modified and delayed from Christmas 1984 to July 24, 1985, so that the movie could be reworked. After 14 years of development, the movie was released on July 24, 1985, receiving mixed reviews from critics and becoming a box-office bomb.
 * Blair Witch 3: A third film in the Blair Witch franchise was in talks since the October 2000 release of Book of Shadows: Blair Witch 2. Despite rumors, development did not begin until September 2009 when creators Daniel Myrick and Eduardo Sánchez announced a third film in the works from Lionsgate, retconning any events from Book of Shadows. After several scripts were tossed around, Simon Barrett's script was pitched with Adam Wingard announced as director in 2013 under its working title, The Woods. The film—simply under its name, Blair Witch—was released on September 16, 2016, with polarizing reactions from critics and audiences, and was a disappointment at the box office.
 * The Bob and Larry Movie: A film adaptation based on the Christian cartoon series VeggieTales was in development since early 2000s. This would have been an origin story of the show hosts Bob the Tomato and Larry the Cucumber which would have revealed how they got their show made and would have explored how the fruit and vegetables were able to talk. This would have featured humans in the film and would've be the first VeggieTales-related media to do so. After the box office bomb of Jonah: A VeggieTales Movie, Big Idea Entertainment fell into bankruptcy and the film got put on a hiatus due to the film's budget. In 2008, it was considered to be the sequel to The Pirates who Don't Do Anything: A VeggieTales Movie, but talks stalled after the 2008 recession had led to the bankruptcy of VeggieTales owner Entertainment Rights and Classic Media. Series creator Phil Vischer claims that he has a copy of The Bob and Larry Movie on his laptop but can't share it due to being owned by Universal Pictures and DreamWorks Animation. However, Big Idea is facing limbo due to problems going on which lead to the departure of some key members of Big Idea thus putting the film in limbo.
 * Bone: A film adaptation of the 1991 comic of the same name was in development since the late 90s with one attempt being under Paramount under the Nickelodeon Movies banner, A later attempt was under Warner Bros. in 2008 with another later attempt in 2016 with Warner Bros. Feature Animation. An animated series by Netflix Animation was announced in 2019, but later cancelled in April 2022.
 * Call of Duty: Upon the release of Call of Duty: Black Ops III, it was reported that Activision Blizzard launched a studio called Activision Blizzard Studios and have plans for a film adaptation based on first-person shooter game series of the same name. Stefano Sollima was attached to direct the film while Chris Pine and Tom Hardy were considered to be the lead roles for the Call of Duty film. The plot of the film would've been described as a real soldier movie and not a war movie. The film was originally going to begin filming in 2019 just to eye for a 2020 or 2021 release. However, Sollima revealed that the film is indefinitely put on hold because it is not Activision's priority.
 * Captain Planet and the Planeteers: Multiple attempts have been made to create a film adaptation based on the environmentalist superhero cartoon series. The earliest was in 1996 when it was just simply titled Planet. Years later, Michael Reaves revised the concept as Dark Planet or Planet and it would have had a story much darker than its source material complete with a post-apocalyptic time period but the script was lost when Turner and Warner Bros. merged in 1996. Other attempts were made in 2007, 2011, and 2013,. Later in 2016, Paramount Pictures and Appian Way Productions were attempting to develop a new movie with Glen Powell as the titular superhero. In early 2023, Powell claims that hurdles at Warner Bros. Discovery need to be cleared before moving forward.
 * Cats: A film adaptation of the musical of the same name was in development in the early to mid 90s. As an animated adaptation by Amblimation but was abandoned with the studio's closure. In December 2013, Andrew Lloyd Webber, creator and composer of the musical stage production Cats, teased that Universal Pictures, which had purchased the film rights to Cats many years earlier, was putting the project into active development. In February 2016, it was reported that Tom Hooper was in negotiations to direct the film, and was considering actresses, including Suki Waterhouse, to star. In May 2016, Hooper was confirmed as director. In January 2018, Hooper and Working Title began officially casting for the film, while looking into the technical aspect of whether the film would be entirely live-action or animated, with Lloyd Webber announcing he would be writing a new song for the film adaptation. On 24 October 2019, it was announced that the new song was titled "Beautiful Ghosts", written by Lloyd Webber and Taylor Swift. The song was sung by Francesca Hayward, followed later in a reprise by Judi Dench, with a credits version sung by Swift. The version sung by Swift was released on 15 November 2019.
 * Catwoman: An adaptation of the comic character as a spin-off of the 1989 Batman series since Batman Forever with Tim Burton as director and producer Denise Di Novi and writer Daniel Waters also returned. Waters turned in his Catwoman script to Warner Bros., the same day Batman Forever was released. Burton was still being courted to direct. Waters joked that "turning it in the day Batman Forever opened may not have been my best logistical move, in that it's the celebration of the fun-for-the-whole-family Batman. Catwoman is definitely not a fun-for-the-whole-family script". In an August 1995 interview, Pfeiffer reiterated her interest in the spin-off but explained her priorities would be challenged as a mother and commitments to other projects. Ashley Judd as the lead in 2001,  but she eventually dropped out so Nicole Kidman was considered. When Warner Bros. canceled a Batman vs. Superman film scheduled for 2004, the studio decided to quickly produce Catwoman as replacement, starring Halle Berry. Berry chose to be involved with the film after the cancellation of Jinx, a James Bond spin-off featuring her character Giacinta "Jinx" Johnson from Die Another Day (2002). Josh Lucas was considered for the role of Tom Lone.
 * A Confederacy of Dunces: The Pulitzer Prize-winning novel has had a motion picture adaptation announced at least seven times, with some of the attempts even making it to a full script being written and most of the major characters of the novel cast, only to always stall and be abandoned.
 * Dallas Buyers Club: The screenplay was written in September 1992 by Craig Borten. Through the 1990s he wrote ten different scripts, hoping for it to be picked up. It was unable to secure financial backing, going through three different directors, finally being released in 2013, with Jean-Marc Vallée directing.
 * The Dark Tower: An adaptation of The Dark Tower had been in development since at least 2007. The film was eventually released on August 4, 2017.
 * Deadpool: Deadpool was in development hell for more than 15 years. In May 2000, Artisan Entertainment announced a deal with Marvel Entertainment to coproduce, finance and distribute a film based on American comic books publisher Marvel Comics character Deadpool. In February 2004, New Line Cinema attempted to produce a Deadpool film with writer/director David S. Goyer working on the spin-off and actor Ryan Reynolds in the title role; Reynolds himself became interested in the character after finding out that in Cable & Deadpool, Deadpool refers to his own scarred appearance as "Ryan Reynolds crossed with a Shar Pei".  By August, Goyer lost interest in favor of other projects. In March 2005, after New Line put Deadpool in turnaround, 20th Century Fox became interested in moving forward on production for the project. Fox considered a Deadpool spin-off early in the development of X-Men Origins: Wolverine, which had Reynolds cast in the role, and after the opening weekend success of that film announced that it was lending Deadpool out to writers, with Lauren Shuler Donner acting as a producer. Donner wanted the film to reboot the character of Deadpool, ignoring the version in X-Men Origins: Wolverine and including attributes that the character has in the comics, such as breaking the fourth wall. Rhett Reese and Paul Wernick were hired to write the script in January 2010, and Robert Rodriguez was sent an early draft of the screenplay that June. After negotiations with Rodriguez fell through, Adam Berg emerged as a top contender to direct. In April 2011, visual effects specialist Tim Miller was hired as director, making the film his directorial debut. In September 2014, Fox gave the film a release date of February 12, 2016. The film was released on that date to positive reviews  and became the ninth highest-grossing film of 2016 worldwide, as well as the highest-grossing R-rated film of all time, until it was surpassed by its own sequel, Deadpool 2, which itself was later surpassed by the film Joker.
 * Death Note: This 2017 neo-noir supernatural teen horror film, loosely based on the Japanese manga and anime of the same names respectively, was in development since August 2007. The American production company Vertigo Entertainment was originally set to develop the remake, with Charley and Vlas Parlapanides as screenwriters and Roy Lee, Doug Davison, Dan Lin, and Brian Witten as producers. On April 30, 2009, Variety reported that Warner Bros., the distributors for the original Japanese live-action films, had acquired the rights for an American remake, with the original screenwriters and producers still attached. In 2009, Zac Efron responded to rumors that he would be playing the film's lead role by stating that the project was "not on the front burner". On January 13, 2011, it was announced that Shane Black had been hired to direct the film, with the script being written by Anthony Bagarozzi and Charles Mondry. Warner's studios planned to change the background story of Light Yagami into one of vengeance instead of justice and to remove Shinigami from the story. Black opposed this change, and it had not been green-lit. Black confirmed in a 2013 interview with Bleeding Cool that he was still working on the film. In July 2014, it was rumored that Gus Van Sant would replace Black as the film's new director, with Dan Lin, Doug Davison, Roy Lee and Brian Witten producing through Vertigo Entertainment, Witten Pictures and Lin Pictures. The film was eventually directed by Adam Wingard and was distributed by Netflix for an August 2017 release and received mostly negative reviews.
 * Deep: Shane Acker expressed interest in creating more animated projects aimed for older audiences due to the severe lack of them. Like 9, Deep would have been another darker animated film and will take place in a post-apocalyptic world (although set in a different universe). There were no further announcements, but a Facebook profile of the character "the Scientist" was updated with a rather cryptic message. The profile had been inactive since 2009, leading some to speculate the teasing of a sequel.
 * Die Hard 4: A fourth installment in the Die Hard franchise was in the works since 1998 with David Marconi, screenwriter of the film Enemy of the State, penning under its working title, WW3.com and using John Carlin's Wired magazine article entitled "A Farewell to Arms", Marconi crafted a screenplay about a cyber-terrorist attack on the United States. After the September 11, 2001 attacks, the project was stalled, only to be resurrected several years later and rewritten into Live Free or Die Hard by Doug Richardson and eventually by Mark Bomback. Willis said in 2005 that the film would be called Die Hard 4.0, as it revolves around computers and cyber-terrorism. IGN later reported the film was to be called Die Hard: Reset instead. 20th Century Fox later announced the title as Live Free or Die Hard and set a release date of June 29, 2007 with filming to begin in September 2006.  The film was the only film in the franchise to receive a PG-13 rating. It was a moderate box office hit, but as with the first three films, it received positive reviews from critics and audiences.
 * Dinosaur: The film was pitched back in 1988 by Phil Tippett as a stop motion animated film then in 1994 was changed to a CGI animated film after seeing Jurassic Park. The film also had problems with the story, Having many drafts written and even with the final draft a lot of cuts to the film had to be made. The film was in development for 12 years until its final release in 2000.
 * Disney's Don Quixote: Ever since the 1940s, Disney wanted to do an adaptation of Don Quixote with various attempts being different from one another with various mediums for each different version including live action and animation with the latest news of Disney adapting the story was 2016.
 * Dragon's Lair: Since the 80s, Dragon's Lair faced plans for a film adaptation but otherwise went to development hell. The first attempt was a fully animated film titled Dragon's Lair: The Legend which would have focused on how Dirk and Daphne met as teenagers and Mordroc was set to be involved in the plot. It would have also explained why Dirk was mute with ideas like being born mute or losing his voice due to a spell or event in the feature film. Despite this, Michael J. Fox was considered to voice Dirk. The first attempt never got made due to low interest from studios. Eventually on 2015, Don Bluth and Gary Goldman made a Kickstarter page to pledge for a potential fully animated film based on the game of the same name. The story would provide more backstory to Dirk and Daphne, but the latter's "sexualized" appearance would be toned down. In 2020, it was announced that Netflix approved a live action adaptation of the game complete with Ryan Reynolds playing as Dirk.
 * Duke Nukem: Since the 90s, a film adaptation based on the shooter game series was in development. The earliest was when Lawrence Kasanoff announced he was working on the film. Plans were announced during 2001 for a live action Duke Nukem movie to be produced by Kasanoff's company Threshold Entertainment. in 2008, Scott Faye said that was planning to produce the movie. Gearbox Software CEO Randy Pitchford hinted on the making of the film in a 2017 interview. In 2018, John Cena was announced as the star playing as Duke Nukem himself. Legendary Entertainment acquired the rights to make a Duke Nukem film with the team behind Cobra Kai involved in production.
 * Evangelion: 3.0+1.0 Thrice Upon a Time: The fourth and final installment of in the Rebuild of Evangelion tetralogy, based on the anime series Neon Genesis Evangelion, was announced alongside Evangelion: 3.0 You Can (Not) Redo as the final part of the Rebuild tetralogy under its working title Evangelion: Final, as double feature for release in 2008.   Originally scheduled for a release in 2020, it was removed due to concerns over the COVID-19 pandemic thus later being rescheduled for January 23, 2021 until January 14, 2021, when the film was removed from the release calendar again.  The film was finally released in Japan on March 8, 2021, to favorable reviews.
 * The Family Guy Movie: A theatrical film based on the hit Fox series Family Guy was announced since July 2007, over two years after the series was revived from cancellation, but series creator Seth MacFarlane declared it as "nothing official" at that time. In TV Week on July 18, 2008, MacFarlane confirmed plans to produce a theatrically released Family Guy feature film sometime "within the next year." He came up with an idea for the story, "something that you could not do on the show, which [to him] is the only reason to do a movie." He later went on to say he imagines the film to be "an old-style musical with dialogue" similar to The Sound of Music, saying that he would "really be trying to capture, musically, that feel." On October 13, 2011, MacFarlane confirmed that a deal for a Family Guy film had been made, and that it would be written by himself and series co-producer Ricky Blitt. On November 30, 2012, MacFarlane confirmed plans to produce a Family Guy film. The project was put on hold while MacFarlane worked on Ted 2. On August 10, 2018, Fox announced that a live-action/animated film based on the series is in development. In July 2019, MacFarlane confirmed that there will be a Family Guy movie, though the acquisition of 21st Century Fox by Disney has made the timeline for the film's development and release unclear.
 * Fantasia 2000: During Walt Disney's time when the original Fantasia was released, Disney himself considered making more segments for the film and thought of releasing the film in a continual release whereas new segments would replace older ones. It was scrapped due to the film's box office reception and mixed reviews from critics. In 1980, animators Wolfgang Reitherman and Mel Shaw worked on a spiritual successor to Fantasia titled Musicana which would've mixed jazz, classical music, myths, modern art, etc. The idea of a Fantasia sequel was revived shortly after Michael Eisner became chief executive officer of The Walt Disney Company in 1984, when Walt's nephew, vice chairman Roy E. Disney, suggested it to him at a lunch. André Previn was at one point going to work on the sequel but refused to do so after learning that the sequel would feature songs from The Beatles rather than typical classical music. It took a further seven years before the film was reconsidered, after the 1990 reissue of Fantasia grossed $25 million domestically and the announcement of its limited availability on home video in 1991 prompted 9.25 million pre-orders. Disney saw its commercial success as a sign that there was enough public interest in the Fantasia franchise to make a sequel. Eisner finally gave the green-light to the film in 1991, and had Disney serve as executive producer on the basis that its production was funded by the proceeds from the video sales. Production began under the working title Fantasia Continued but was changed to Fantasia 1999 and later Fantasia 2000. It was originally going to be a "semi-new movie" where it would feature most segments from the original Fantasia with only a few new segments but it didn't work out well so the older segments had to be trimmed down to three consisting of The Sorcerer's Apprentice, The Nutcracker Suite, and Dance of the Hours. The former was chosen eventually as the only returning segment to feature in 2000. There was even some unused segments that were meant to be in the final film which include Clair de Lune and Rhapsody on a Theme of Paganini. The film was officially announced on February 9, 1999 and was released on January 1, 2000 via IMAX and June 16, 2000 in the United States.
 * The Flash: Development of a film based on the comic book character of the same name began in the late 1980s when Warner Bros. hired comic book writer Jeff Loeb to write a treatment. The project was later revived in December 2004 when David S. Goyer was brought on to write, direct, and produce a new version of The Flash after penning the script for Batman Begins. After Goyer left the project in February 2007 over creative differences, Shawn Levy was hired to direct with a new draft written by Chris Bancato, before both abandoned the project in October 2007 and David Dopkin was hired to revamp it as a spin-off to George Miller's then-planned film, Justice League: Mortal, with Adam Brody cast as the character. Justice League: Mortal was later cancelled and the film was stuck in further development caused by the 2007-2008 Writers' Guild of America strike. Warner Bros. began development again as part of their newly established DC Extended Universe in July 2013, with a planned release date of 2016. In October 2014, Ezra Miller was cast as the character, with a theatrical release planned for March 23, 2018. Miller portrayed the character onscreen in Batman v Superman: Dawn of Justice (2016), Suicide Squad (2016), and Justice League (2017). Several directors, including Seth Grahame-Smith, Rick Famuyiwa, and filmmaking duo John Francis Daley and Jonathan Goldstein, left the project over creative differences at various points from 2016 to 2018. Christina Hodson and Andy Muschietti were confirmed to be writing and directing, respectively, in November 2019. Pre-production began in January 2020, with Principal photography lasting from April to October 2021 at Warner Bros. Studios, Leavesden. After multiple post-production setbacks and controversies surrounding Miller, the film was released on June 16, 2023, and became a commercial failure.
 * Foodfight!: In 2004, the CGI film Foodfight was announced. Described as "Toy Story in a supermarket", the film promised to bring together over 80 famous advertising characters with voice talent including Charlie Sheen, Christopher Lloyd, Eva Longoria, Hilary and Haylie Duff, and Wayne Brady. Director Lawrence Kasanoff expected it to be a commercial hit and merchandise for the movie appeared on store shelves before the film had a release date. However, the film ran into many problems. In late 2002/early 2003, Kasanoff reported that hard drives containing unfinished assets from the film had been stolen in what he called an act of "industrial espionage." However, those who worked on the film did not recall this happening, with one assistant claiming that the original hard drives were saved and stored properly and believed that Kasanoff was simply not satisfied with them. A behind-the-scenes showreel Kasanoff put together to entice investors is the only significant surviving footage of the original incarnation of the film. After several years, a trailer was finally shown at AHM in 2011, a company bought the DVD distribution rights for the film in Europe, and a quiet video-on-demand American release came in 2012.
 * Freddy vs. Jason: A crossover between Freddy Krueger and Jason Voorhees was first attempted in 1987, but fell apart due to disagreements between Paramount Pictures and New Line Cinema, the respective owners of Friday the 13th and A Nightmare on Elm Street. After the release of Jason Goes to Hell: The Final Friday, which teased Freddy vs. Jason, New Line Cinema spent roughly $6 million on several unused scripts from over a dozen screenwriters, but eventually, Mark Swift and Damian Shannon produced a script that went into production. The film experienced controversy when it was announced Kane Hodder, the longtime actor for Jason, was to be replaced by a different actor, and experienced further controversy when it was revealed that the original 120-page script was to be cut down by a different writer. Both Swift and Shannon had to deal with studio interference and hesitation, as well as fighting a PG-13 rating and having to send out a questionnaire to gauge interest in the concept. Finally, the film released on August 15, 2003, and grossed $116.6 million worldwide on a production budget of $30 million to a mild critical response.
 * Frozen: Beginning development in 1940 as a biopic about Hans Christian Andersen's life, progress on the Disney–Goldwyn project halted in 1942 as the United States entered World War II, with Disney shifting its focus to wartime propaganda. Between 1992 and 2002, Disney attempted a revival of the project, with multiple versions of the film now stored in their Animation Research Library. These versions removed key elements such as a troll and a mirror, requiring creative solutions for the character Kai's departure. Attempts included a story line in Iceland where Kai joins a whaling ship to impress Gerda, while the Snow Queen rides an orca. Other versions experimented with adding comic side characters to the narrative but no one was able to transform the minimally defined characters and episodic plot into a compelling narrative. That was until it was put back into production in 2008 with Chris Buck and Jennifer Lee as directors and was released in 2013.
 * Hellraiser: A remake of the original 1987 film was first announced by Clive Barker in October 2006 in which he stated he was writing the script and it was going to be produced by Dimension Films. He also announced that Pascal Laugier was set to direct, but he was later taken off the project due to creative differences. Then in October 2010, Patrick Lussier and Todd Farmer were announced to be writing and directing the film, but in 2011 they said they were also taken off the project despite drafting multiple scripts with different ideas. Two years later in October 2013, Clive Barker announced he was to head a Hellraiser reboot starring Doug Bradley in his ninth film as Pinhead but he announced in 2017 on Twitter that the script had been sent to Dimension Films years ago with no correspondence since. Finally, Spyglass Media Group and David S. Goyer were confirmed to be working on a Hellraiser remake in May 2019, and in 2020 David Bruckner, Ben Collins and Luke Piotrowski were also confirmed to be directing and writing the script. In October 2021, principal filming finally wrapped up; it was revealed that Jamie Clayton was to be playing Pinhead and the film was coming out on Hulu.
 * The Incredible Mr. Limpet: Development for a remake of the 1964 film of the same name started in 1996 with Jim Carrey in the lead role and Steve Oedekerk as director. By March 1999, Oedekerk left the project following creative differences, while Carrey followed suit in July the same year. In April 2000, Mike Judge was also set to direct with filming set to begin in February 2001. In June 2009, Kevin Lima was attached to direct. In 2010, it was reported that Zach Galifianakis was in talks for the lead role. In March 2011, Richard Linklater entered negotiations to helm the project, and was announced as the director in January 2014. That same month, Femke Wolting and Tommy Pallotta had begun working on the design and animation on the project while Galifianakis would reportedly play the lead character. On July 8, 2014, it was announced that Jon Hamm, Danny McBride, Sarah Silverman, Kevin Hart, Josh Gad, Keegan-Michael Key, and Jordan Peele had entered talks for various roles in the film. On August 4, Linklater left the project to concentrate on his next film That's What I'm Talking About (released in 2016 as Everybody Wants Some!!).
 * ID Forever Part I and II: The sequels to Independence Day were in development hell from 1997 until 2009, when director Roland Emmerich announced the pre-production of the films, which were planned to be shot back-to-back. However, ID Forever Part I was renamed to Independence Day: Resurgence for its release on June 24, 2016.
 * The Irishman: The film had been in development since 2007. It went on to have its world premiere at the 57th New York Film Festival on September 27, 2019, and received a limited theatrical release on November 1, 2019, followed by digital streaming on November 27, 2019, by Netflix.
 * Untitled The Jetsons film: Not to be confused with Jetsons: The Movie. Since 1985, there were various attempts to make a film adaptation of the Hanna-Barbera show of the same name. The earliest was a live-action film by Paramount Pictures but it never got made. In 2001, Paul Foley and Dan Forman were hired to revise a screenplay with Rob Minkoff and Denise Di Novi as director and producer respectively. Then came 2007 where Robert Rodriguez was in talks to make a live-action film based on the animated sitcom though he was uncertain about what project to pursue next. In 2012, the latest announcement for a live action Jetsons film was that Van Robichaux and Evan Susser were hired to rewrite the script. Then in 2015 it was announced that Warner Animation Group would develop a live action Jetsons film. As of May 2017, Conrad Vernon became the director of the film.
 * Jim Henson Idea Man: Since 2010, a biopic based on the life of Jim Henson has been in development at Walt Disney Pictures and The Jim Henson Company. Lisa Henson is the producer of the biopic while Michael Mitnick wrote the script. The film is finally set to be released on May 31 of 2024.
 * John Carter: Several attempts to adapt the Barsoom series had been made since the 1930s by various major studios and producers, including a cartoon animated by veteran Bob Clampett. In the 1980s, film producers Mario Kassar and Andrew G. Vajna bought the rights for Walt Disney Studios via Cinergi Pictures, with a view to create a competitor to the original Star Wars trilogy and Conan the Barbarian. Ted Elliott and Terry Rossio were hired to write, while John McTiernan and Tom Cruise were approached to direct and star. The project collapsed when McTiernan realized that visual effects were not yet advanced enough to recreate Burroughs' vision of Barsoom. The film was picked up at Paramount Pictures in the early 2000s and several directors, Robert Rodriguez, Kerry Conran, and Jon Favreau, came and exited the project before Paramount decided not to renew the film rights. Eventually filmmaker Andrew Stanton lobbied Disney to reacquire the rights, and he was hired as director for his live action directorial debut. The film was released in 2012 as one of the most expensive films ever, and was a notorious flop at the box-office.
 * Jurassic World: The fourth film of the Jurassic Park series was in development hell ever since the release of Jurassic Park III in 2001 when it was first announced. After scheduling and release conflicts, the fourth film was eventually retooled as a soft reboot known as Jurassic World, which was released theatrically on June 12, 2015.
 * Untitled Keith Moon biopic: For more than 15 years, The Who lead singer Roger Daltrey had a planned biopic based upon the late English drummer. Mike Myers was at one point intended to be the star of the biopic in an early attempt. Later on after many years of development hell, Daltrey said that he was pleased with a script for the film and thus he vowed that the film can still be made.
 * The Legend of Zelda: Since 2007, Nintendo's Zelda series faced plans for a film adaptation. The earliest was when Imagi Animation Studios wanted to make an animated film adaptation of the video game franchise and thus made a pitch reel for a CGI Zelda movie. However, their version of the film got cancelled due to Nintendo not wanting to repeat the same mistakes as what happened with the live-action Super Mario Bros. film. In 2013, Eiji Aonuma talked about how he wanted to make an interactive Zelda movie where players could bring their Nintendo 3DS into the cinema and players can participate in the film somehow. Around June 2023, there were rumors suggesting that after the success of The Super Mario Bros. Movie, Universal and Illumination wanted to do a fully animated film adaptation of the video game series. However, Illumination CEO Chris Meledandri denied the rumors. In November 2023, it was finally announced that a live-action Zelda movie is in the works with Wes Ball directing while Shigeru Miyamoto and Avi Arad being the producers. According to Miyamoto, he claims that he's been working on a Zelda movie for "many years".
 * Live 2 Tell: A film based on the rapper Tupac Shakur's screenplay that he had written during his incarceration in 1995, about a drug dealer's tale of redemption. The project goes back to 2005, where IMDb listed it as currently in-production pending further development. No information was published until 2011 when a company named NStar Studios picked up the project and planned to put it into production in 2012. With an estimated budget of $11 million, a crowdfunding campaign was started to raise $250,000 in 30 days, but it failed and NStar was never able to get the project off the ground. As of 2021, the film is still listed on IMDb with no further information available.
 * Mad God: This stop motion experimental horror film had been in development for 30 years.
 * Mad Max: Fury Road: In 1995, George Miller re-acquired the rights to future Mad Max films from Warner Bros. The idea for a fourth instalment occurred to Miller in August 1998 when he was walking in an intersection in Los Angeles. About a year later, while travelling from Los Angeles to Australia, the idea coalesced. Miller conceived a story where "violent marauders were fighting, not for oil or for material goods, but for human beings." The film was set to shoot in 2001 through 20th Century Fox, but was postponed because of the September 11 attacks that same year. "The American dollar collapsed against the Australian dollar, and our budget ballooned", Miller said, adding that he "had to move on to Happy Feet because there was a small window when that was ready". Mel Gibson, who starred in the original three previous films, would not return to his role as the lead character. Miller ended up re-casting the role because of controversies surrounding Gibson and because he wanted Max to remain at a younger age, as the "same contemporary warrior". Miller announced in 2003 that a script had been written for a fourth film, and that pre-production was in the early stages. The project was given the green light to begin filming in the Australian desert in May 2003 with a budget of US$100 million, but the location was ruined by rainfall. Mad Max 4 then entered a hiatus in light of security concerns related to its Namibian shoot because of tightened travel and shipping restrictions at the onset of the Iraq War. In 2007, after focusing on the animated musical comedy Happy Feet, Miller decided to pursue the project again. He briefly considered producing Fury Road as an animated film but abandoned it in favor of live-action. In 2009, Miller announced that filming would begin in early 2011. Tom Hardy was cast as the title character in June 2010, with production planned to begin that November. Principal photography was delayed several more times before beginning in July 2012. The film wrapped in December 2012, although additional footage was shot in November 2013. The film was finally released on May 15, 2015, to critical acclaim, although after the release of the film in question, there has been an ongoing pay dispute between Warner Bros. and Miller as to producing future sequels.
 * Mai, the Psychic Girl: This film based on the sci-fi manga series did had a film planned out since the 1980s. Pop and rock duo Sparks wanted to turn the manga into a musical with Tim Burton involved in the film but it never gotten around due to Burton wanting to work on other projects. In the 1990s, Francis Ford Coppola got his hands into the project while eventually a new project for the film adaptation was said to be directed by Kirk Wong. Sparks claimed that for six years the band tried to get their Mai film produced with Russell Mael stating "The music is all ready and we are hoping that this still might see the light of day". In 2010, Burton expressed renewed interest in adapting the property.
 * The Man Who Killed Don Quixote: A loose adaptation of the Don Quixote tale co-written and directed by Terry Gilliam. Production originally started in 1998, but during shooting in 2000, a significant number of difficulties such as the set and equipment being destroyed by flooding, the departure of the film's lead owing to illness, problems obtaining insurance for the production, and other financial difficulties led to a sudden suspension of the production and its subsequent cancellation. Part of the development hell is shown in documentary Lost in La Mancha. Gilliam made several additional attempts to revive the project   until filming finally completed in 2017 and the finished film was released the following year.
 * Mary Poppins Returns: The sequel to Mary Poppins had been in development since the 1960s, and was in development hell until its release in 2018.
 * Me and My Shadow/Edgar Wright's Shadows: DreamWorks Animation's film about shadows is infamous for having troubled production due to various factors going on at DreamWorks Animation thus putting the shadows movie in limbo currently. Public attention has risen high of the unreleased shadows film a whole decade after it was announced and during its limbo. Though many are eager to see it, the fate of the DreamWorks shadow film is uncertain.
 * Megalopolis: A passion project by Francis Ford Coppola, the film was developed since 1983 and underwent significant delays and numerous cancellations over the years. However, the film was revived again since 2019.
 * Mega Man: Since December 2014, 20th Century Fox announced a film adaptation based on the Mega Man video game series by Capcom. In September 2015, Chernin Entertainment and its CEO Peter Chernin were going to produce the film, with David Ready and Michael Finfer overseeing the production for Chernin, while Mike Ireland and Ryan Horrigan were overseeing for Fox. Henry Joost and Ariel Schulman were in the final negotiations to write and direct the film for both Fox and Chernin when Masi Oka joined as a producer. Capcom in 2018 announced that a live-action film is in development and it was part of Capcom's plans to increase value to the Mega Man franchise following the release of Mega Man 11 and was set to depict the series through a higher-budgeted film production. In 2019, The Walt Disney Company acquired Fox while Bob Iger announced eventually that several films in development at Fox would not be progressing and the Mega Man film is one of them. That October, Capcom announced that the film is still happening. Eventually, Chernin made a deal with Netflix. Later, it was revealed that Mattson Tomlin shared his own version of the script that it was going to explore the titular character as a real person. Supermarché was revealed to be developing the film alongside Chernin Entertainment for Netflix with Orlee-Rose attached to produce. The film would explore the future of automation and "man and robot becoming one" as either good or bad. Josh Koenigsberg was also writing a new draft of the screenplay and said he had replayed past Mega Man games to research the property.
 * Metal Gear: Since May 2006, a film adaptation of the series was in development with the film being based on Metal Gear Solid according to Hideo Kojima. Producers had expressed interest in Equilibrium director Kurt Wimmer as writer and/or director, or Paul Thomas Anderson to direct. Viggo Mortensen and Hugh Jackman were considered for the role of Snake. In January 2010 Michael De Luca claimed that work on the Metal Gear film has been postponed believing that the entire Metal Gear franchise could seriously get affected if the film adaptation performs poorly. The film was revived in 2012 just as soon as Kojima said that Arad Productions and Columbia Pictures will be working on the film with Sony Pictures distributing the film. Jordan Vogt-Roberts became the director of the film and said that the script for the film could be an R or PG-13 rating. The script has been completed and Jordan wanted an R rated Metal Gear film thus another draft was completed. So far, the most recent news for the film is that Oscar Isaac got officially cast as Solid Snake. Oscar previously has expressed interest in the role.
 * Minecraft: Since February 2014, Markus Persson announced that Mojang Studios was in talks with Warner Bros. Pictures to develop an official Minecraft film to be produced by Roy Lee and Jill Messick. The film was said that it might be released in 2018 due to its "large-budget". Shawn Levy was set to direct the film but left the project. In 2015, Rob McElhenney got hired to direct the film and claims that he had been drawn to the film based on the open-world nature of the game and was given a release date of 2019 while Jason Fuchs is set to write the script and Steve Carell is set to star in the film. Eventually, McElhenney's version of the film died down due to scheduling conflicts. Aaron and Adam Nee were tapped to rewrite the film yet it was delayed as a result so no new director was announced at the time. In 2019, Peter Sollett will write and direct the film and it will have a different story compared to McElhenney's version while the late Messick will be credited as producer. The film was set to be released in March 2022. the COVID-19 pandemic prompted Warner Bros. to adjust its release schedule. Jared Hess became the new director while Jason Momoa got into some early talks to star and Matt Berry was in negotiations to join the cast. The film now has a release date of 2025. Principal photography on the film would start in New Zealand, but it was delayed in July due to the 2023 SAG-AFTRA strike.
 * Untitled second The Nightmare Before Christmas film: Plans for a sequel of The Nightmare Before Christmas were as early as 2002 when Disney wanted to do a sequel that would use computer animation rather than stop motion. In 2009, Henry Selick did express interest in doing a sequel if he and Burton had a good story for it. In 2019, it was announced that a new Nightmare Before Christmas film is in the works with Disney in the form of either a stop motion sequel or a live-action remake. Chris Sarandon had interest on reprising his role as Jack Skellington if a sequel film ever materializes. On October 14, 2023, Selick stated that he was inclined to do a prequel film of  how Jack became king of Halloween Town.
 * Pac-Man: Various attempts for a feature film based on Pac-Man have been planned since the peak of the original game's popularity. Following the release of Ms. Pac-Man, a feature film was being developed, but never reached an agreement. In 2008 however, a live action film was announced with Crystal Sky Pictures developing the film. In 2022, plans for the live action Pac-Man film were revived at Wayfarer Studios, based on an idea by Chuck Williams.
 * Pinocchio: A darker stop-motion animated adaption of the Italian novel The Adventures of Pinocchio was conceived by Guillermo del Toro in 2008. On February 17, 2011, it was announced that Gris Grimly and Mark Gustafson would co-direct the film written by del Toro and Matthew Robbins. On May 17, 2012, del Toro took over for Grimly. The movie was initially scheduled to be released in 2014, but no new information regarding the film was made public for several years during this period of development hell. In January 2017, Patrick McHale was announced to co-write the script. On August 31, 2017, del Toro told that the film need a budget increase of $35 million. In November 2017, del Toro reported that the project was cancelled, because no studios were willing to finance it. However, on October 22, 2018, it was announced that the film had been revived by Netflix. The film was finally released in December 2022 to critical acclaim.
 * The Postman: Author David Brin described the ten-year effort to get his novel produced as a film. Production began in 1987, but the final film was not released until 1997. In the process, the screenplay went through so many revisions that the shooting script only loosely resembled the book, and writers later "borrowed" elements from the book to improve the film. The film was a box-office bomb and was negatively reviewed.
 * Puss in Boots: The Last Wish: A sequel to the 2011 Shrek spin-off, Puss in Boots, was announced in November 2012 by Guillermo del Toro. In 2014, voice actor Antonio Banderas announced that work had begun and it was tentatively titled Puss in Boots 2: Nine Lives and 40 Thieves. The film was further stuck in limbo by the corporate restructuring of DreamWorks. In 2018, Chris Meledandri signed on as an executive producer alongside another Shrek film. The film was released on December 21, 2022, and was a critical and commercial success, being nominated for Best Animated Feature at the 95th Academy Awards.
 * Ray Gunn: Since late 1995, director Brad Bird was developing an animated film for Turner Entertainment but the WarnerMedia merger happened and thus it got scrapped. However, Bird announced that he wants to revive the project at Skydance Animation years later.
 * Red Sonja: A second Red Sonja film has been in development for some years. In 2008, Robert Rodriguez and his production company Troublemaker Studios were working on a version that would have starred Rose McGowan as the titular character. By 2009 however, the Rodriguez project had been scrapped, and in February 2010, rights holders Nu Image announced they were moving forward with another projected new film, to be directed by Simon West. Producer Avi Lerner said he would like to see Amber Heard take the role of Sonja. In 2018, Bryan Singer was confirmed to be the director at one point but was dropped out due to recent sexual allegations with Singer. In June 2019, Joey Soloway signed on to write, direct and produce the film. Soloway left the project alongside Hannah John-Kamen who was originally going to star in the remake and thus M. J. Bassett was hired as the new director. This film is currently a reboot film that is supposed to be released in 2024.
 * Saints Row: Rapper 50 Cent said he was working on a screenplay based on the action adventure video game series thus starting development of a Saints Row film since 2009. F. Gary Gray in 2019 said he will be directing the film with Greg Russo working on the script.
 * Sangam (Hindi for "Union") is an Indian film that was in development hell for at least 15 years. It was originally developed under the original title Gharoanda (Hindi for "nest", literally "house of twigs"), but was withheld by company R.K. Films for a couple of reasons. Then, in 1963, it was remade as Sangam and starred Raj Kapoor, Vyjayanthimala, and Rajendra Kumar, among others. It was released in 1964 with a duration of about 4 hours, being the first Hindi film with two intervals. It was a box office success.
 * Shrek 5: A fifth film of the Shrek series was as planned as May 2004 just after the success of Shrek 2. Jeffrey Katzenberg revealed that the Shrek story had been outlined into five films almost from the beginning. The fifth film was going to reveal how Shrek came to be in his swamp. However, DreamWorks Animation and Bill Damaschke said that Shrek Forever After would be final film of the series. Katzenberg in an interview during the year of 2014 said that a fifth Shrek film can still be made. Since NBCUniversal bought DreamWorks Animation in 2016, Steve Burke had plans to continue the series as well as other DreamWorks films. Later that year, Eddie Murphy claims that a fifth Shrek film could release in 2019 or 2020 and the script was already complete. Michael McCullers wrote the script while Chris Meledandri is said to be the executive producer. Meledandri also stated much later in 2023 that the fifth film was still in talks with the original cast being expected to return.
 * The Simpsons Movie: The idea for a film adaptation was considered back in 1992 in the early years of the series, but did not materialize due to the lack of experience on making a theatrical film. The film took around 15 years to be released in 2007.
 * The Sims: Since 2007, this life simulation video game series was set to get a live-action film with 20th Century Fox working on it. The film was in development for years until the merger with Fox and Disney. However, LuckyChap Entertainment and Vertigo Entertainment revived the project in March 2024.
 * Sin City: A Dame to Kill For: A sequel to the 2005 film Sin City was announced shortly after that film was released. Director Robert Rodriguez and creator Frank Miller planned for the film to be based on A Dame to Kill For, with the latter stating that it would be a prequel and a sequel, and that the script would be done by 2006 and production would begin later that same year. However, Rodriguez had also said that official casting would not start until the script was finalized and in the studio's hands. In March 2012, Rodriguez announced that production on Sin City 2 would begin in mid-2012. He also mentioned that the cast would be "of the same caliber and eclecticism" as that of the previous film. It was also announced the film would be released in 3D. On April 13, 2012, production of the film was confirmed, in addition to a new title, Sin City: A Dame to Kill For. The film was expected to go into production in the summer of 2012, but principal photography began near the end of October 2012. On June 17, 2013, the film's release date was pushed back from October 4, 2013, to August 22, 2014. Rodriguez later explained that the film was always intended for release in 2014 and that they were merely holding the October date for Machete Kills. Unlike its predecessor, the film was a critical and commercial failure, but would gain a cult following on its home and digital release later on.
 * Sonic the Hedgehog: The film based on Sega's own flagship video game character was in development hell as early as 1994, when studios such as Metro-Goldwyn-Mayer and DreamWorks dropped the script for a Sonic film. It was only in 2013 that Sony Pictures announced that its Columbia Pictures brand and Original Film acquired the rights to the video game series and the film would be a joint venture with Sega's owned Marza Animation Planet and Blur Studio. In October 2017, Paramount Pictures announced that they had acquired the rights after Sony's Columbia Pictures put the film into turnaround. In February 2018, it was announced that the film would be released on November 15, 2019. However, after negative reactions from the first trailer, the studio changed its official theatrical release date to February 14, 2020, for more retooling by Moving Picture Company.   The film was a box office success and received favorable reviews from critics.
 * Space Jam: A New Legacy: A sequel to the 1996 live-action/animated hybrid Space Jam was in the works in 1997, with Joe Pytka from the first film to direct, Bob Camp to design an all-new character, Berserk-O! and his henchmen, and Spike Brandt and Tony Cervone signing on as the animation supervisors. The potential sequel reentered development as Spy Jam and was to star Jackie Chan in a different script. The studio was also planning a film titled Race Jam, which would have starred Jeff Gordon. Additionally, Pytka revealed that following the first film's success, he had been pitched a story for a sequel that would have starred professional golfer Tiger Woods, with Jordan in a smaller role. Pytka explained how the idea came from an out of studio script conference, with people who worked on the original film allegedly involved. Another idea for a Space Jam sequel, entitled Skate Jam, was in early development with Tony Hawk in the starring role. Plans were underway for production to begin immediately following the release of Looney Tunes: Back in Action, but it was cancelled given that film's poor box office performance despite otherwise improved critical reception from Space Jam. Over 10 years later however, talks for a sequel were resurrected with LeBron James as the main star. Filming began from June 25 to September 26, 2019, with Malcolm D. Lee helming as director.  In addition, in March 2020, photos during the shooting were leaked as Warner Bros. characters outside the Looney Tunes franchise would also appear in the film, such as Superman, Batman, Pennywise, Scooby-Doo and Shaggy, Harry Potter, Joker, Gollum, Bane, Scorpion and Sub-Zero, Agent Smith, Mad Max, Finn and Jake, The Mask, the Gremlins, Tom and Jerry, Austin Powers, King Leonidas, George the Gorilla, Dr. Manhattan, Harold and Kumar, Yakko, Wakko, and Dot, Rick and Morty among others.  The film, titled Space Jam: A New Legacy, was released on July 16, 2021, to generally negative reviews.
 * Speed Racer: A live-action Speed Racer film was in the works since 1992 when Warner Bros. optioned the rights to make a film version of it in conjunction with Silver Pictures. In October 1994, singer Henry Rollins was offered the role of Racer X. In June 1995, Johnny Depp was cast into the lead role for Speed Racer, with production slated to begin the coming October, In September 2000, Warner Bros. and producer Lauren Shuler Donner hired writer-director Hype Williams to take the helm of the project. In June 2004, Vince Vaughn spearheaded a revival of the project by presenting a take for the film that would develop the characters more strongly. Vaughn was cast as Racer X and was also attached to the project as an executive producer. With production never becoming active, Vaughn was eventually detached from the project. However, the Wachowskis were brought on board by the studio to write and direct the film in October 2006. The film was released on May 9, 2008. Although critics gave it mixed reviews and was a box office bomb, it was received positively by fans and garnered a cult following.
 * Spy Hunter: Since the summer of 2003, Universal Pictures acquired the rights to the 1983 arcade game of the same name from Midway Games. In September, Dwayne Johnson was going to star in the film adaptation based on the game with Michael Brandt and Derek Haas got hired to write the screenplay despite no director being decided at the time. Later on John Woo was attached to direct the movie while Zak Penn replaced previous screenwriters. In April 2005, Stuart Beattie replaced Zak for screenwriter yet on May on the same year John Woo left the project due to scheduling conflicts. Pre-production work was underway with designs such as the morphing Interceptor vehicle driven by Alex Decker. Production was halted as Dwayne Johnson was detached from the project. However, a game based on the movie titled SpyHunter: Nowhere to Run got released despite its film not getting released. In 2007, Paul W. S. Anderson became the new director to replace Woo with a new script unrelated to Nowhere to Run but he left due to his commitment to Death Race 2 as a producer. In 2013, Warner Bros. - due to Warner Bros. Games owning the assets of Midway Games - announced that Ruben Fleischer was brought on board to direct.
 * Strange Magic: The idea for this film was in development since 2000 alongside the Star Wars prequels, with it being conceived by George Lucas as "Star Wars for 12-year-old girls" and pitched as a Beauty and the Beast story where the Beast doesn't change. The film would be released in 2015.
 * Superman Lives: The name given to a project begun by producer Jon Peters in 1993 as Superman Reborn. The proposed film would have followed the comic story line known as The Death of Superman. Jonathan Lemkin was hired to write the initial script, but Peters brought on a series of additional screenwriters to overhaul the script, including Gregory Poirier in 1995 and Kevin Smith in 1996. Director Tim Burton became attached to the film, with Nicolas Cage cast as the Man of Steel, and several more screenwriters were brought on board for several more rewrites. Burton backed out in late 1998 citing differences with producer Peters and the studios, opting instead to direct Sleepy Hollow. Additional writers and directors were attached to the project at various times over the next few years. Peters' project went through several more permutations before evolving into Superman Returns, released in 2006, 13 years after initial development began. The film's journey through development hell was later explored by a documentary on the topic, The Death of "Superman Lives": What Happened?, released in 2015.
 * Tangled: Since 1996, Disney wanted to do an adaptation of the Brothers Grimm story Rapunzel. At one point, it was originally going to be called Rapunzel Unbraided which is supposed to have a Shrek-like tone and would have centered around two teenagers who live in San Francisco and how they ended up in a fairy tale world where they ended up inheriting the bodies of Rapunzel and the prince Beau respectively while the actual Rapunzel and Beau would've turned into a squirrel and a dog. It took until 2010 to get the film released.
 * Terminator 3: Rise of the Machines: A third installment in the Terminator franchise was announced even before Terminator 2: Judgment Day was released. In July 1991, while the sequel was in its theatrical run, Cameron said that if the film was successful then "there may be some economic pressure" to do a sequel.  When Carolco Pictures, the production company behind the second film, filed for bankruptcy in 1995, director James Cameron was hired to come back and direct the third film for 20th Century Fox. A year later, when Cameron's 3D film ride, Terminator 2 3-D: Battle Across Time, would open, the project team reunited the main cast of the second film and prompted Cameron to begin writing a script for a Terminator 3 film, despite him being too busy working on Titanic for 20th Century Fox during that time. Eventually, former Carolco founders Mario Kassar and Andrew G. Vajna founded C2 Pictures, and rights for the third film were backed by German and Japanese investors by 1999. Jonathan Mostow was set to direct, and Arnold Schwarzenegger returned by 2000, despite his focus on the 2002 California gubernatorial elections two years later during filming. The film was released on July 2, 2003, and was met with mixed reception with critics, fans, and the general public, but nevertheless was a box office success.
 * The Thief and the Cobbler: Originally conceptualized in 1963, the film was released in 1993, although under a slightly different title.
 * Untitled Thomas & Friends film: After the box-office bomb of Thomas and the Magic Railroad, there wasn't any new Thomas theatrical films until later in late 2000s-to-early 2010s it was announced that a new Thomas film is currently in development. Shane Acker was set to direct the film with the film now being titled The Adventures of Thomas and Wētā FX was doing the visuals for the film. In 2020, it was later announced that Marc Forster is directing a new Thomas the Tank Engine film.
 * Tomb Raider: A film reboot of the franchise of the same name was announced by producer Graham King and studios Metro-Goldwyn-Mayer and Warner Bros. back in 2009. Stars like Olivia Wilde, Kristen Stewart and Megan Fox were originally slated to audition the role as Lara Croft. It was announced in 2015 during the release of 20th Century Fox's Hitman: Agent 47 that Adrian Askarieh, producer of the Hitman films, stated that he hoped to oversee a shared universe of Square Enix-based films, with Just Cause, Hitman, Tomb Raider, Deus Ex, and Thief, but admitted that he does not have the rights to Tomb Raider. In May 2017, the Game Central reporters at Metro UK suggested that the shared universe was unlikely, pointing out that no progress had been made on any Just Cause, Deus Ex nor Thief films. Deadline Hollywood had previously reported that Daisy Ridley was considered for the role, though she later stated in an interview with Vogue that it was just the "craziest rumor" she had ever heard about herself. Eventually, the role was given to Alicia Vikander as the titular character and the film was released on March 16, 2018, with mixed reception from critics. A sequel, with MGM being the sole distributor, was scheduled to be released on March 19, 2021 until September, when it was delayed to an unknown release date due to the COVID-19 pandemic, before being cancelled in 2022 after MGM's film rights to the Tomb Raider series expired.
 * Tom & Jerry: Plans for a theatrical Tom and Jerry movie were drawn up in 2009 as a live-action animated film following the success of Alvin and the Chipmunks. 6 years later, Warner Bros. wanted to place a renewed focus on animation, and plans changed from a full-on live-action film to a full-on animated film. 3 years later, plans have officially been finalized as a live-action/animated hybrid that began to film in 2019, originally planned to be released on April 16, 2021, before being pushed back for a December 23, 2020 release. The film was officially released on February 26, 2021.
 * Treasure Planet: An animated outer space adaptation of Treasure Island described as "Treasure Island in space" was pitched as far back as 1985 with constant rejection from then-Disney CEO Michael Eisner and then-chief of Walt Disney Studios Jeffrey Katzenberg until 1997; after the release of Hercules, the film was greenlit for release in 2002. The film was a box office bomb and received mixed-to-positive reviews from critics.
 * Tron: Ares: Plans for a 3rd Tron film were as early as 2010s. The first draft of the script was complete under the name of "TR3N". In 2015, the film got delayed by Disney and it was mostly blamed on the box office bomb of Tomorrowland. Despite all this, actor Jared Leto was cast as a new character named Ares during the years between 2016 and 2017. In 2020, Garth Davis was announced to be the director of the film with Leto's role as one of the main characters still intact. At one point, Davis was removed as director with Joachim Rønning got into negotiations to replace him. The film was planned to be filmed on August 14, 2023, but it got delayed due to the 2023 Hollywood labor disputes. Later on, the film is said to begin filming following the holiday season.
 * Uncharted: A film based on Naughty Dog's Uncharted games was in development since 2008 when film producer Avi Arad stated that he was working with a division of Sony to develop a film adaptation of Uncharted. Principal photography began on March 16, 2020, with Ruben Fleischer directing, but was shut down in mid-March 2020 due to the COVID-19 pandemic. Production resumed on July 20,  and filming concluded on October 29, 2020. Owing to the COVID-19 pandemic, the film's release date was delayed to October 8, 2021. The film was moved up to July 16, 2021, taking the original release date of Spider-Man: No Way Home, before releasing on February 11, 2022.
 * Warcraft: A live-action adaptation of the Warcraft series was first announced in 2006. The film spent several years in development hell before the project advanced. It was scheduled for a 2016 release. The film was released in June 2016 worldwide with a Paris premiere in May.
 * Watch Dogs: Since 2014, Ubisoft wanted to work on a film based on the action-adventure video game franchise. The film's announcements were on a hiatus until it was announced that Sophie Wilde will be starring in the film.
 * Watchmen: The 2009 film based on the Alan Moore graphic novel from DC Comics had undergone much various production problems, such as penning the script from four different studios and directors and attaching different screenwriters for the project. Development was halted for twenty years until 2006, when Zack Snyder, fresh out of production of the then-soon-to-be-released 300, was hired as director for the film. It was eventually released on March 6, 2009, with mixed reactions from critics and moderate success worldwide at the box office, but received more acclaim from fans gaining more of a cult following over the years.
 * Where the Wild Things Are: A film adaptation of the Maurice Sendak children's book of the same name that was in development since 1983, being tossed around to various studios, starting at Disney as a traditionally hand-drawn animated adaptation directed by John Lasseter in 1988. In 2001, plans for a CGI adaptation of the film produced under Universal Pictures and directed by Eric Goldberg were reverted to live-action and later produced under Warner Bros. in 2009.
 * Untitled Who Framed Roger Rabbit sequel: Plans for a Roger Rabbit sequel was as early as 1989 where J. J. Abrams wrote a script yet it was eventually abandoned. Nat Mauldin wrote a prequel titled Roger Rabbit: The Toon Platoon (later renamed as Who Discovered Roger Rabbit) which would still feature characters from The Golden Age of American animation and it would have had Roger live on a farm during his early days and traveling to the west to seek his mother. He also meets Jessica who happens to be his future wife. Roger was also going to be in the army while Jessica was kidnapped to do pro-Nazi Germany broadcasts and thus Roger and new character Ritchie Davenport goes on a quest to save her and thus being accompanied by several other Toons in their army. It would also reveal that Roger would reunite with his mom as well as his dad Bugs Bunny. It was cancelled because just as soon as Steven Spielberg saw the script, he left due to not wanting to satirize Nazism after directing Schindler's List. Eventually it was reworked into a different story (Roger would have found himself in rising stardom on Broadway and Hollywood while still searching for his mother) in and test footage was made in Lake Buena Vista, Florida which consisted of CGI, traditional animation, and live-action which didn't please Disney. A second test entirely made the Toons CGI but the film was scrapped due to budget reasons. Don Hahn doubts that a sequel would be made due to the rise of computer animation. In 2009, another attempt was made through ImageMovers yet the human characters will be done via Motion capture much like films including The Polar Express and Disney's A Christmas Carol while the Toons would still remain in traditional animation. It was cancelled eventually due to Bob Hoskins' retirement from acting in 2012 and later his eventual death, the unsatisfactory performance of A Christmas Carol, and the failure of Mars Needs Moms which lead to projects like the Roger Rabbit sequel, Calling All Robots, a remake of Yellow Submarine, and The Nutcracker to be cancelled. Later, Zemeckis said that a sequel could still be possible without Hoskins. In 2013, it was announced that an animated Disney buddy comedy film starring Mickey Mouse and Roger called The Stooge which would have been based on the 1952 film of the same name and would have been a prequel. In 2016, Zemeckis said that the sequel moves the story of Roger and Jessica into the next few years thus moving on from film noir to the world of the 1950s. It would also feature a "digital Bob Hoskins" due to Eddie being depicted as a ghost in the film. While hand drawn is still going to be used in the film, the chances of Disney green-lighting the film are "slim". In 2018, Zemeckis claims that Disney is unlikely to ever make the sequel.

Television

 * Big Nate: A TV series based on the comic strip of the same name since 1991 for a Saturday-morning cartoon on NBC. Lincoln Peirce "was paid $5,000 to write a quote-on-quote bible describing the characters and outlining a few story ideas". However, the day after this deal was finalized, NBC cancelled their Saturday Morning cartoons line up, It would get a second attempt on Paramount+ in 2022.
 * The Boys: A film based on the comic series The Boys was in various stages of development between 2008 and 2016 with several names attached to the project such as Adam McKay, Phil Hay and Matt Manfredi. Russell Crowe and Simon Pegg were asked to play Billy Butcher and Hughie respectively but declined. However, it was scrapped in favour for a television series headed by Eric Kripke, Evan Goldberg and Seth Rogen and was to be developed by Cinemax. In November 2017, it was announced that Amazon had given the production a series order for a first season of eight episodes and it had its premiere in 2019 at the San Diego Comic-Con.
 * Crash Bandicoot: A TV series based on the video game was in development since the first games inception with the unused cutscenes for the first games being a semi-pitch for the series which were uploaded to YouTube by producer David Siller in 2015. In 2007, The Animation Picture Company produced four web-short films, to promote the game Crash of the Titans, titled Crash Bandicoot: No Use Crying, Crash Bandicoot Monster Truck, Crash Bandicoot – Titan Idol and Crash Bandicoot – Have Another, all lasting for about three minutes. These are available for free download on the Xbox 360 video service or are available to watch on the web, originally available for viewing on the Crash Bandicoot official website. Crash Bandicoot's appearance Skylanders Academy in the episode Crash Landed was also a lead way into a possible series. On January 13, 2021, test footage from a scrapped Crash Bandicoot series was leaked on Reddit. The series would have been a co-production between Activision and Amazon Studios. The series was allegedly canceled due to a script dispute.
 * The Magic 7: Is a half animated/live-action TV Special that started development in early 1990 and would have featured an all star voices cast of John Candy, Madeline Kahn, Michael J. Fox, James Earl Jones, Jeremy Irons, Ice-T and Dirk Benedict and live action cast of Kevin Bacon, Bette Midler, and Judy Collins appear as themselves in live action roles. The film was delayed and shelved for many year due to lack of funding and the deaths of both Candy and Kahn were also a factor.
 * Muppets Haunted Mansion: Attempts for a Halloween special for The Muppets went back as the early 90s. Following Jim Henson's death, his son Brian planned to continue the franchise's presence on television by releasing a series of holiday specials, with the first one tentatively centered around Halloween. Although those plans never went through the story for the special was used in the video game Muppet Monster Adventure. In March 2009, it was announced during a special event at Disney's Hollywood Studios, that The Walt Disney Company, who acquired The Muppets in 2004, was developing a Halloween special based on the franchise. A 2010 release date was later announced. However, the special was postponed in order for The Muppets Studio to focus entirely on the 2011 film, and eventually cancelled. In May 2021, a Muppets Halloween special based on the Disney theme park attraction The Haunted Mansion, titled Muppets Haunted Mansion, was announced to be in development. Filming took place in April 2021 during eighteen days. In August 2021, longtime Muppet director Kirk Thatcher revealed that he wrote and directed the special, and shared a teaser image from it.
 * Phineas and Ferb: The show was pitched to many networks for 15 years such as Cartoon Network, Nickelodeon, and Fox Kids until it landed on Disney Channel in 2008.
 * ReBoot: The series was conceived in 1984 and went through 8 years of development until the series reached it's detailed look in 1991 due to the limitations of CGI at the time, future episodes were produced in the remaining years until they aired in 1994.

Music

 * Alpha: The debut studio album by South Korean rapper and singer-songwriter CL went through several delays and cancellations since was first announced in 2014 when she signs with Scooter Braun and SB Projects.
 * Brainwashed: Released posthumously as the twelfth and final studio album by Beatles member George Harrison, 15 years after his previous studio album Cloud Nine. Recordings began over a decade before Harrison's death but were repeatedly delayed.
 * Chinese Democracy: Rock band Guns N' Roses began work on this album in the late 1990s. In the time between its conception and release, nearly the entire lineup of the band had changed numerous times. It was once dubbed "The Most Expensive Album Never Made" by The New York Times. Recorded in 14 separate studios with reported production costs of $13 million, Chinese Democracy was eventually released in November 2008.
 * Closure/Continuation: The eleventh studio album by British progressive rock band Porcupine Tree is their first since 2009's The Incident. Despite public uncertainty of the band's future after frontman Steven Wilson's focus on a solo career in 2010, the album was recorded intermittently in complete secrecy among Wilson, Gavin Harrison, and Richard Barbieri across the course of the following decade, without long-time bassist Colin Edwin. With the COVID-19 pandemic putting members' separate plans on hold, the band found time to completely finish the album in September 2021. Towards the end of the year, the band's reformation was publicly announced, alongside the album's release date of 24 June 2022.
 * Detox: A studio album by American hip hop recording artist Dr. Dre, slated to be his swan song album, was originally slated for release between 2011 and 2012 through Aftermath Entertainment and Interscope Records. Production for Detox began in 2000, but has been delayed several times as Dr. Dre wanted to concentrate on producing for artists that were on his Aftermath record label. Work for the upcoming album dates back to 2001, where its first version was called "the most advanced rap album ever," by co-producer Scott Storch. Even at the beginning of Detox's production, it was announced that it would be Dr. Dre's final studio album, which had been confirmed at different points throughout the album's 10-year production process. Because Dr. Dre had stated he was tired of rapping about marijuana use and a stereotypical gangster lifestyle, he planned to make Detox a hip-hop musical telling the story of a professional hitman and his family, with an intended summer 2003 release date. Initially announced in 2000 after the release of Dr. Dre's previous album 2001 (1999), Detox went through many iterations during its 11-year production period, failing to have a confirmed release date due to Dr. Dre believing the project "wasn't good enough". However, the album spawned two official singles, "Kush" and "I Need a Doctor". In January 2004, Storch listed guest appearances such as 50 Cent, Eminem, Game, and Snoop Dogg. Keri Hilson told Rap-Up that she had recorded material for the album but was unsure if the tracks would make the final cut. J. Cole stated that he recorded with Dre but refused to explain further. The album's production was eventually cancelled on August 1, 2015, with Dr. Dre instead releasing a brand-new album, Compton, inspired by the concurrent production of the film Straight Outta Compton, a week later on August 7.
 * Fear Inoculum: Tool frontman Maynard James Keenan announced at the 50th Grammy Awards in February 2008 that the band would start working on a follow-up to their 2006 album 10,000 Days "right away". However, a number of creative, personal, and legal issues delayed the writing and recording of the album, which was eventually released at the end of August 2019.
 * Good-Ass Job: The initial fourth studio album from Chicago hip hop recording artist Kanye West announced in a 2003 MTV article detailing West's plans for his first four studio albums. Good-Ass Job was meant to follow Graduation however, after the passing of his mother and the end of his engagement to Alexis Phifer, 808s & Heartbreak was released instead. Despite some speculation on a potential revival of the Good-Ass Job project during the making of My Beautiful Dark Twisted Fantasy, no information came out regarding the termination or continuation of the album. In September 2018, during Chance the Rapper's Open Mike event in Chicago, West made a surprise appearance and announced that he was working on a collaborative studio album with Chance titled Good-Ass Job. Although, after the critical and commercial failure of Chance's debut studio album The Big Day, the collaborative project has seemingly been cancelled as no news has come out since and Chance's relationship with West significantly soured during the recording of Donda, West's tenth studio album.
 * i/o: The tenth studio album from British art pop musician Peter Gabriel, i/o began production in April 1995 following the conclusion of Gabriel's Secret World tour, concurrently with his seventh studio album, Up (itself not released until 2002).  Gabriel originally stated that the album would be released in 2004, only for extensive touring in support of Up to delay these plans considerably. Gabriel repeatedly gave vague updates on the album's production over the following years, first stating in 2008 that he was "shifting focus" towards both i/o and his cover album Scratch My Back (which saw release in 2010) before later claiming in 2011 that i/o was still just a number of unfinished "song ideas" that he had yet to elaborate upon. Gabriel would continue to post about the album's production during the remainder of the 2010s, ultimately stating on BBC Radio in April 2019 that he was planning on finishing songwriting for i/o by the end of the year. Despite his plans to "get a record out" by early 2020, the album was delayed further as a result of lockdowns imposed in the wake of the COVID-19 pandemic. In an interview with Uncut magazine for their September 2020 issue, Gabriel stated that despite the delays, "I have enough songs to make a record I'm proud of," and that a complete album could be expected at an indeterminate point in the future. The album's lead single, "Panopticom", was eventually released on January 6, 2023, with additional singles coming out each successive full moon that year. The full album was released on December 1, 2023, 28 years and eight months after production began and nearly two decades after its originally announced release date. i/o received notoriety for its repeated delays, with Rolling Stone calling it the "Chinese Democracy of Peter Gabriel albums", and Stereogum calling it "the Smile (or perhaps the Chinese Democracy) of art-rock."


 * Look Outside Your Window: An unreleased studio album recorded by four members of the American band Slipknot. The material was written and recorded concurrently with the sessions for the band's fourth studio album All Hope Is Gone (2008). However, its emphasis on experimentation and a more melodic rock style kept it classified as a separate body of work from Slipknot's aggressive heavy metal sound. The album was scheduled for release during the latter half of the band's We Are Not Your Kind touring cycle, which was postponed due to the COVID-19 pandemic. After a few years of uncertainty, on January 2, 2023, percussionist Shawn Crahan spoke about the possibility of the album being released later this year.
 * The Smile Sessions: Archival recordings of the Beach Boys' unfinished album Smile took nearly 45 years to compile for a dedicated release. Numerous complications contributed to its excessively protracted delay, including bandleader Brian Wilson's irrational fear of the album. Brother and bandmate Carl Wilson compared the album's structuring to editing a film, as compiler Alan Boyd explains, "I think he was right about that. The kind of editing that the project required seemed more like the process of putting a film together than a pop record."
 * Starship: A studio album by Italian electronic band Eiffel 65, this would be their fourth album since 2003, and the first one after ending their "Bloom 06 project" in 2010. Members Gianfranco Randone and Maurizio Lobina reunited that same year with Gabry Ponte, who had left the band in 2005 to "reunite once again to produce new music as well as touring". In an April 2012 interview, Jeffrey Jey commented that "within the next two or three months" they would release "some" songs online. Four years after, on June 1, 2016, they released "Panico/Critical", their first single in twelve years. They have toured Europe with their "New Planet Tour" since 2010, mainly in Italy, and occasionally in other European countries, as well as in Australia in 2012. As of 2021, the band is semi-active; Gabry Ponte has stated that he does not participate in record production and concerts, but he has never officially left the group either. In 2020, Italian rapper Shiva released a single called "Auto Blu ft. Eiffel 65", which is a remake of Blue (Da Ba Dee) with different lyrics. Some unreleased Eiffel 65 songs have been leaked, but the album remains unreleased almost ten years after its announcement, five years after their last original single was released, and eighteen years after their last studio album was released, with no further details or release date set for their new album, if ever.
 * Still Sucks: This is the sixth album from American nu metal band Limp Bizkit, released a decade after the band's fifth album Gold Cobra was released in 2011. Production began when they left Interscope and signed up with Cash Money Records in February 2012, with attempts to release a new album under its initial name Stampede of the Disco Elephants. The first single "Lightz (City of Angels)" was released on October 26, 2012. After many delays, the second single for the album, "Ready to Go", featuring label mate Lil Wayne was released on April 16, 2013, to positive reviews. The band officially left their previous label Cash Money Records on October 26, 2014. In February 2016, Metal Injection reported that the band was still in the studio recording the new album. The album remained unreleased, with no release date set for several years. Guitarist Wes Borland has already completed writing and performing guitars for the record, but stated in late 2017 that frontman Fred Durst is still working on his parts. Borland again reiterated the band's progress in November 2018. In July 2017, Durst claimed on Instagram that the album had already been available online for a year and a half on Soulseek, but Borland refuted this saying he "doesn't know what [Durst] is talking about." In August 2021, the band announced they would begin releasing songs in close succession, leading up to the album's release, before announcing the album title as Still Sucks and the release date. The album was released on October 31, 2021, to positive reviews. None of the previously released singles were included on the album.
 * Time II: This is the upcoming fourth album by Finnish metal band Wintersun and a follow-up to their 2012 album Time I. Both albums were planned to be one full album tentatively titled Time. As of the commencement of recording in May 2006, frontman Jari Mäenpää stated that the album length would run over 65 minutes, and that it would be a concept album. Furthermore, according to Mäenpää, the album's sound was to be highly intricate. Each song was said to contain about 200 tracks. On February 27, 2009, Mäenpää announced through Wintersun's official website that the band would cancel all their live appearances, including Bloodstock Open Air and Summer Breeze, in order to make way for the slow progress of the album. On April 26, 2010, Mäenpää announced on the Wintersun message board that "Land of Snow and Sorrow" was completely finished and that the tracks "Storm" and "Silver Leaves" would be done soon. On November 17, 2010, the band members announced on Wintersun's official website that the album was close to being completed for the most part and that the synths and orchestrations might be finished around December 2010/January 2011. Jari intended to start mixing the album afterwards. On December 25, 2010, Jari stated on the Winter Madness message board that "Silver Leaves" was finished except for some orchestrations. On December 26, 2010, Jari stated that three songs are finished and ready for mixing, and that four songs have "bits and pieces" missing, including vocals. On March 19, 2011, Jari announced via the Winter Madness message board that mixing had been put on hold until late summer at the earliest due to various complications, ranging from a lack of 64-bit DAW plugins to noisy nearby construction. Time was eventually announced to be split into two halves and released separately, with the titles of Time I and Time II. Time I was released in October 19, 2012 in Europe and October 22, 2012 in North America. Since then, production of Time II was marred with years-long delays for a multitude of reasons, until 12 January 2024, when Wintersun announced on its social media that Time II is "100%" complete. Three days later, on 15 January 2024, the band announced that "the album release will happen in the late summer of 2024, the latest early fall" and a second crowdfunding campaign was also announced. On 9 February, the band revealed the track list and cover art for Time II. On 26 February, the band announced Time II would be released on 30 August.
 * United World Rebellion: This is what was planned to be a trilogy of two extended plays and one studio album from the American heavy metal band Skid Row that was meant to last a year or two, but ended up being a decade because of the studio album's delays. United World Rebellion: Chapter One was released on April 16, 2013, and is the band's first EP since 1995. The recording was released by Megaforce Records and sold 1,500 copies in its first week in the US. "Kings of Demolition" was released as a single and features a music video. "This Is Killing Me" was released as the second single and also features a music video. Rise of the Damnation Army – United World Rebellion: Chapter Two was released on August 5, 2014, by Megaforce, and sold 1,300 copies in the US in its first week. "We Are the Damned" was released as a single and features a music video. United World Rebellion: Chapter Three, originally scheduled for release in 2015 but pushed back to 2016 following Solinger's departure from the band and then pushed back again due to Tony Harnell's sudden departure. When released it was expected to feature new lead singer ZP Theart. Originally planned to be the third EP which will complete the United World Rebellion album, the band has now stated in an interview that chapter 3 will be a full-length studio album. According to guitarist Dave "Snake" Sabo, it was expected to be released on September 16, 2022. The third chapter was ultimately scrapped with the band's next record having the title The Gang's All Here instead, and Erik Grönwall as lead vocalist instead of Theart.
 * Untitled Minecraft album: C418, who was originally the sole producer of Minecraft ' s original soundtrack, has been planning to release a third soundtrack album as a follow-up to 2011's Minecraft - Volume Alpha and 2013's Minecraft - Volume Beta. However, the third album has been delayed indefinitely from its original 2017 release window, and its fate remains uncertain as C418 officially resigned from working on Minecraft in late 2021; the game's version 1.13 update in 2018 contains the only new music that's been contributed to the game itself by C418 since the release of Volume Beta. In a 2021 interview, when asked about the album, he said he "considered it finished" but things had become complicated with Minecraft, so he was unsure if it would ever release.
 * Untitled X Japan album: The upcoming sixth studio album by Japanese heavy metal band X Japan was initially planned to be half new songs and half re-recordings of old songs; this was abandoned at some point in its 10 years of production in favour of all-new material. Several different release dates were announced in that time, but the album remains unpublished despite drummer and bandleader Yoshiki confirming its completion in September 2018. However, several songs reported to be on it have been made commercially available digitally. If released, it will be X Japan's first album of new material in two and a half decades, their first since reuniting in 2007, their first to feature newest member Sugizo, and their final album with longtime bassist Heath, after his death in 2023.
 * Wildflower: The second studio album by Australian electronic music group the Avalanches. After the release of their debut Since I Left You, the group toured for three years and collaborated with various musicians, such as Luke Steele in 2003. The first song made after the debut was Saturday Night Inside Out. These sessions would produce early versions of songs which made the final cut, such as Colours. During this time, member Robbie Chater was ill for three years with two autoimmune diseases, leaving him unable to produce music and further delaying the project. The group attempted several projects, including collaborations with Ariel Pink, Jennifer Herrema, and Danny Brown (the origin of Frankie Sinatra), and a psychedelic hip-hop animated feature film of Yellow Submarine (the origin of The Noisy Eater). By 2014, all members had left except Chater and Tony Di Blasi, and the record label Modular had announced that "Album sounds awesome, but there's no dates or anything planned. The official line is 'stay tuned.'". Wildflower was released in July 2016 and features remnants from these projects, with re-edits, rewrites and production lasting from 2000 until 2016.

Video games

 * Aliens: Colonial Marines: First announced in 2001, Aliens: Colonial Marines spent over 12 years in development hell. The original game, which was announced in 2001 to be in development by Check Six Games, was cancelled. The video game rights for the Alien franchise were sold in December 2006 to Sega. Gearbox Software subsequently announced that it would take over development of Colonial Marines, intending it to be a direct follow-up to Aliens. The game would spend another 7 years in development, during which Gearbox's resources were also being consumed by other projects, such as Duke Nukem Forever, as well as its own franchise Borderlands, resulting in much of the game's development being outsourced to other studios. The game was released in 2013, where it was criticized for having various bugs and gameplay issues, low-quality graphics, as well as a lack of consistent continuity with the Alien film franchise. Further controversy emerged when it was found that Gearbox and Sega had presented demos of the game at conventions that had a noticeably higher graphics quality than the final product.
 * Beyond Good and Evil 2: An upcoming sequel to the 2003 video game, Beyond Good & Evil. The original was released in 2003, was critically praised and gained a cult following, but was considered a commercial failure. Its director said in a May 2008 interview with the French magazine Jeuxvideo.fr that a Beyond Good & Evil sequel had been in pre-production for a year, but was yet to be approved by Ubisoft. Ubisoft officially announced a sequel in 2016.  Ubisoft showed the first new trailer for Beyond Good and Evil 2 during their E3 2017 conference, with it being announced as a prequel to the first game.
 * Dead Island 2: Published by Deep Silver, Dead Island 2 was first pitched as the sequel to Techland's Dead Island in 2012, however would instead be shifted to Yager Development, then Sumo Digital and finally Dambuster Studios during the decade-long production cycle, eventually releasing in 2023.
 * Diablo III: Development began in 2000 by Blizzard North and continued until the studio closed in 2005. An entirely new development began in 2006, and the game was released in 2012.
 * Duke Nukem Forever: The sequel to the 1996 game Duke Nukem 3D, Duke Nukem Forever, was in development hell for 14 years: from 1997 to its release date in 2011, earning it the nickname “Duke Nukem Fornever”. The long development time was caused by numerous factors, including a switch from the Quake II engine to the Unreal Engine, having a relatively small development staff by modern standards (3D Realms' co-owners George Broussard and Scott Miller infamously maintained that the game would be released "when it's done"), conflicts between 3D Realms and its publisher, Take-Two Interactive, over how it had been handling the constant delays, and the eventual bankruptcy of 3D Realms. In 2009, the rights to the Duke Nukem franchise were sold to Gearbox Software, who eventually completed the game and released it in 2011.   The game was ultimately a critical disappointment, with most of the criticism directed towards the game's clunky controls, long loading times, offensive humor, and overall aged and dated design.   The game eventually proved to be profitable, according to a statement by Take-Two during its earnings call in August 2011.
 * Earthworm Jim 4: Plans for a fourth installment was in development since 2001 Due to the poor receptions of Earthworm Jim 3D, Doug TenNapel has been pitching and developing ideas for a fourth installment to the series. One was a 2.5D platformer for the Xbox and PlayStation 2 with similar gameplay to Klonoa but was scrapped. In 2006 remake for the PlayStation Portable were planned but also scrapped due to legal issues. Another attempt was announced in 2017 and planned to be released sometime in 2020s for the Intellivision Amico.
 * Final Fantasy XV: Originally titled Final Fantasy Versus XIII, it was announced in 2006 as a spinoff of Final Fantasy XIII exclusively for PlayStation 3. Following a long period with little news on the game, it was re-announced as the next mainline installment of the series on PlayStation 4 and Xbox One which underwent large changes in direction such as making the game a self-contained story and replacing the main heroine. The game was released worldwide on November 29, 2016, more than 10 years after it was initially announced. Additional story content was released post-launch in the form of episodic DLC.
 * Half-Life 2: Episode Three: In May 2006, Valve Corporation announced a trilogy of episodic games that would continue the story of Half-Life 2 (2004). Valve president Gabe Newell said the approach would allow Valve to release products more quickly after the six-year Half-Life 2 development, and that he considered the trilogy the equivalent of Half-Life 3. Episode One was released on June 1, 2006, followed by Episode Two on October 10, 2007. Episode Three was initially planned to be released on Christmas 2007. Concept art surfaced in 2008, and reports surfaced that Valve was working with sign language on a deaf character.   Valve released little information regarding Episode Three in the following years; though Valve still discussed Half-Life, there was no clarity on whether further games were coming. In March 2010, Newell spoke of "broadening the emotional palette" of the series, and said that the next Half-Life game may return to "genuinely scaring the player". In 2011 he said: "We went through the episodes phase, and now we're going towards shorter and even shorter cycles ... For me, 'entertainment as a service' is a clear distillation of the episodic content model." That year, Wired described Episode Three as vaporware. Valve eventually abandoned episodic development. In 2015, Episode 3 was cancelled due to internal conflict with management over at Valve.
 * Kirby's Return to Dream Land: Development began in 2000 immediately following the release of Kirby 64: The Crystal Shards, but the game was not revealed to the public until E3 2005, alongside two other game demos which were both eventually cancelled. Due to development issues, as well as being developed late in the GameCube’s lifespan, the project would not officially be shown again until E3 2011, and the game would finally see a release later that year on its successor, the Wii. Some concepts that were scrapped would eventually be revisited in Kirby Star Allies and Kirby and the Forgotten Land, which were released for the Nintendo Switch in 2018 and 2022, respectively.
 * Metroid Dread: Metroid Dread was intended to be a sequel to Metroid Fusion (2002) by Yoshio Sakamoto but was initially stopped by hardware limitations. The first attempt was made in 2005 for the Nintendo DS and first appeared in a 2005 Nintendo internal software list for "key DS games to be announced in the future"; however, by late 2005, many rumours were circulating that the game was in development hell due to the DS's hardware limitations. The second attempt at the game was a playable prototype shown in E3 2009 behind closed doors. The prototype didn't meet Sakamoto's expectations however, so production was halted in 2010. Despite denying Dread's existence since 2010, Nintendo announced that MercurySteam were developing the revived Metroid Dread for the Nintendo Switch with a release date of October 8, 2021.
 * Mewgenics: First announced in 2012 by Team Meat, the game was intended to be the company's follow-up project to the highly successful Super Meat Boy. Originally set for a 2014 release, the game suffered from feature creep and differences in priorities between Team Meat's owners, Edmund McMillen and Tommy Refenes. The game was initially shelved in 2014, but after two years of no development, was cancelled in 2016. After leaving Team Meat, McMillen acquired the rights to Mewgenics in 2018 and rebooted its production with Tyler Glaiel and new gameplay. It is tentatively set to be released in 2025, over twelve years after its announcement.
 * Mother 3: A sequel to the 1994 Super Famicom RPG Mother 2 (released as EarthBound in 1995 in North America). The game was initially intended to be released on the Super Famicom like its predecessor, starting development shortly after the latter's release, before shifting focus to the Nintendo 64's Disk Drive add-on. Following the failure of the add-on, the media format of the game was shifted to a standard N64 cartridge before the development team's inexperience with 3D-oriented video game creation and a large series of delays led to the game being quietly cancelled in 2000. Eventually, assets from the cancelled project were collected and converted to a 2D format, and the project restarted development on the Game Boy Advance. Twelve years after its conception, Mother 3 was finally released on the Game Boy Advance in 2006, but only in Japan.
 * Six Days in Fallujah: The game was originally scheduled for a release in 2010, but development was soon halted due to the insolvency of the developer studio Atomic Games. It was later revealed in 2021 to have restarted development through Highwire Games, with the game planned to release on 2023. On June 22, 2023, the early access for the game was released.
 * Star Citizen: Development of the game began in 2011, and is being mostly financed from a large crowdfunding campaign. The game was originally planned for a 2014 release, but significant delays in production and expansion of gameplay features meant it had to be delayed indefinitely. Due to mismanagement, some of the early work done for the first-person-shooter module has been scrapped altogether, resulting in wasted financial resources and development time. As of 2023, there is no clear release date for the game.
 * StarCraft: Ghost: StarCraft: Ghost was set to be the first game in a sub-series of games set in the StarCraft universe in the genre of third-person shooters unlike the usual real-time strategy of the series. First announced in September 2002, Blizzard confirmed that the game would be worked on in conjunction with Nihilistic Software for multiple consoles and that the game was aimed for a late 2003 release date however, the game got continuous delays throughout the following months and in 2003, Nihilistic said they were discontinuing their work on the project. Soon after this, Blizzard began collaborating with Swingin' Ape Studios for a September 2005 release date but after the GameCube version was cancelled and the other two console versions were delayed to a year later, Blizzard announced an indefinite postponement of the game in order to explore possibilities of seventh generation video game consoles. Despite sporadic information on the game between 2006 and 2008, Blizzard Entertainment finally officially cancelled StarCraft: Ghost in a 2014 interview with Polygon about the similarly cancelled MMO Titan.
 * Star Fox 2: In 1993, development for a Star Fox sequel began with the intention of releasing it for the Super Nintendo Entertainment System with the implementation of the Super FX 2 chip. However, in 1995, technology was advancing quickly, leading developers to believe that the game would not sell well at the time. Nintendo instead focused on making a new Star Fox game for the Nintendo 64 and thus the sequel game was cancelled. In 2017, the game was released for the Super NES Classic and later on Nintendo Switch Online.
 * The Elder Scrolls VI: The long-awaited sequel to the 2011 hit, The Elder Scrolls V: Skyrim, was announced at E3 2018, however it only began active development after the launch of Starfield in 2023. Being delayed significantly from its originally planned launch in 2024 according to leaked documents, producer Todd Howard said in 2021 that the game would come "some fifteen to seventeen years after Skyrim" (2026 to 2028), and Microsoft Gaming CEO Phil Spencer estimated in 2023 that the game's release was still "five plus years away" (indicating a launch of 2028 or later), suggesting further delays. This would possibly make TES6 a game shipping on a 10th generation console, quite a big jump from its predecessor, Skyrim, that originally launched on 7th generation consoles.
 * Too Human: Announced by the developer Silicon Knights in 1999 to be released on the PlayStation, the game would feature a futuristic take on Norse mythology, as well as an ambitious class system and online multiplayer. Development halted when Nintendo announced an exclusive partnership with Silicon Knights, and the game was moved to the GameCube in 2000, and then moved again to the Xbox 360 when Silicon Knights announced a partnership with Microsoft in May 2005. Silicon Knights also announced plans to develop Too Human into a trilogy. After 9 years in development, Too Human released in 2008 exclusively for the XBox 360. It received mixed reviews and sold poorly, which was followed by with a lawsuit filed against Silicon Knights by Unreal Engine creators Epic Games regarding the Unreal Engine 3 engine used in the game. Silicon Knights was dissolved following the lawsuit and plans for the eventual trilogy were scrapped.