I Know What You Did Last Summer (franchise)

I Know What You Did Last Summer is an American horror film franchise consisting of three slasher films and one television series, loosely based on the novel of the same name by Lois Duncan. The first installment was written by Kevin Williamson, directed by Jim Gillespie, and released in 1997.

The first two installments star Jennifer Love Hewitt, Freddie Prinze Jr. and Muse Watson. Co-starring Sarah Michelle Gellar, Ryan Phillippe, in addition, the supporting cast includes: Johnny Galecki in the first film, with Brandy, Mekhi Phifer and Matthew Settle in the second film.

Novel
In 1973, Lois Duncan's I Know What You Did Last Summer was published. It was republished as a tie-in to the film in 1997 and once again in 2018 with some of its content modernized. The film adaptation reenvisioned the story of the novel as a violent slasher film, as opposed to the slow-burn mystery nature of the novel.

I Know What You Did Last Summer (1997)
After an accident on a winding road, four teens make the fatal mistake of dumping their victim's body into the sea. But exactly one year later, a mysterious fisherman begins stalking the friends.

I Still Know What You Did Last Summer (1998)
The murderous fisherman with a hook stalks the two surviving teens, Julie James and Ray Bronson who left him for dead. Despite Julie's warnings, her friends do not believe her until it is too late, and the fisherman begins a second murder spree at a posh island resort in the Bahamas.

I'll Always Know What You Did Last Summer (2006)
A group of teenagers in Colorado find themselves being stalked and killed one by one by a mysterious figure with a hook, exactly one year after they covered up a friend's accidental death.

Untitled fourth film (2025)
In September 2014, Sony Pictures revealed plans to remake the film, with Mike Flanagan and Jeff Howard writing the script. The film was a high priority and was initially set for release in 2016. The project required an estimated budget of $15–20 million. Flanagan confirmed that his new iteration of the franchise would be a fiction and not include elements of the 1973 novel nor of the 1997 feature film. The project was ultimately never made and was subsequently canceled.

In February 2023, after years of remaining in development hell, a legacy sequel was announced to be in development with Jennifer Love Hewitt and Freddie Prinze Jr. in negotiations to reprise their respective roles. Jennifer Kaytin Robinson will direct the film from a script written by Leah McKendrick, based on an original story co-written by Robinson and McKendrick; while Neal H. Moritz will serve as producer. The plot is said to be similar in approach to Scream (2022), in which characters from the original film are included in a story featuring a younger cast. Later in March, however, Prinze Jr. stated that he had not yet signed on to reprise his co-starring role. In December, Hewitt stated that she will definitely reprise her lead role.

In March 2024, McKendrick revealed that the influence of social media will factor into the film's plot. In May, the untitled film was officially slated for a July 18, 2025 release date. Under Jennifer Kaytin Robinson's direction, from a script co-written by Kaytin Robinson and Sam Lansky, from a previous draft by Leah McKendrick, and based on the original story co-authored by Kaytin Robinson and McKendrick; Jennifer Love Hewitt and Freddie Prince Jr. are in negotiations to reprise their starring roles, while an ensemble cast will factor into the plot. The project will be a joint-venture production between Sony Pictures, Columbia Pictures, and Original Film; while Columbia Pictures will handle distribution.

I Know What You Did Last Summer (2021)
Amazon Studios acquired the rights in July 2019 to develop a television series adaptation with Neal H. Moritz and James Wan producing. Craig Macneill directed the pilot episode, written by Sara Goodman. Madison Iseman, Brianne Tju, Ezekiel Goodman, Ashley Moore, Sebastian Amoruso, Fiona Rene, Cassie Beck, Brooke Bloom, and Bill Heck star in the series. It was released on October 15, 2021.

Novelization
In 1998, a paperback release of the screenplay for I Still Know What You Did Last Summer was published by Pocket Books.