Scooby-Doo! and the Goblin King

'Scooby-Doo! and the Goblin King' is a 2008 American animated comedy horror musical film, and the twelfth in the series of Scooby-Doo direct-to-video films produced by Warner Bros. Animation (though it used a Hanna-Barbera logo at the end of the film). It was dedicated to Paulette Oates, who helped resurrect Warner Bros. Animation in the late 1980s. The DVD was released on September 23, 2008. This is the first Scooby cartoon produced entirely without either one of the original producers, William Hanna and Joseph Barbera.

This film calls back to the shared premise of The Boo Brothers, The Ghoul School, and The Reluctant Werewolf films from the late 1980s, where the fantastical elements of the story are genuine, and Scooby and Shaggy alone discover and befriend an entire society of supernatural beings.

Plot
Mystery Inc. attends the annual Coolsville Halloween carnival, where they encounter a magician called "The Amazing Krudsky". After he refuses to let Scooby-Doo see his latest show for causing an accident, the former and Shaggy Rogers retaliate by publicly exposing Krudsky as a fraud, causing him to swear revenge while the gang are thrown out of the carnival. Nonetheless, they decide to go trick-or-treating instead.

Meanwhile, Fairy Princess Willow enters Krudsky's tent and accidentally reveals the existence of a powerful artifact called the Goblin Scepter. When he decides to find it and use it to take over the world, Willow tries to stop him, but knocks herself out, allowing Krudsky to capture her and absorb her magic to become a real magician.

Concurrently, Shaggy and Scooby discover a "genuine magic shoppe". The proprietor, Mr. Gibbles, reveals to them that magic is real before Krudsky interrupts them while recapturing Willow. He then turns Gibbles into a rabbit and steals his magical equipment before leaving. Realizing Krudsky's plot, Gibbles urges Shaggy and Scooby to stop him, grants them monstrous disguises, sends them to the spirit world, and warns them to return before sunrise lest they be trapped there forever. Upon their arrival, the pair struggle to find the Goblin Scepter's owner, the Goblin King, but eventually encounter Jack O'Lantern and the Grand Witch, who uses her flying broomstick "Broomy" to transport them to the Goblin King's castle, only to be shot down by the monarch's bumbling henchmen, Glob and Glum. Crash-landing in a fairy village in the woods outside the castle, Shaggy and Scooby encounter fairies who help them reach the entrance. They use a potion the Grand Witch gave them to assume new disguises and infiltrate the castle, but their disguises wear off, leading to them being captured and sent to the dungeon, though they are saved by Jack, the fairies, and Broomy.

Elsewhere, the rest of Mystery Inc. discover Krudsky conversing with the Goblin King, who reluctantly agrees to exchange his scepter for Willow, his daughter, at midnight. As Krudsky engages in supernatural chaos, Velma Dinkley faints from being unable to comprehend the events while Fred Jones and Daphne Blake formulate a plan to stop the trade. When midnight arrives, the duo spring their trap, but only succeed in capturing the Goblin King while Krudsky obtains the scepter and leads an army of goblins in taking over the world and turning people into monsters. Soon enough, Shaggy, Scooby, Jack, and Broomy arrive, with Jack sacrificing himself to defeat Krudsky. Scooby grabs the scepter and undoes Krudsky's spells before returning it to the Goblin King. In the aftermath, the Goblin King grounds Willow for a year for causing the mayhem; joins Gibbles in resurrecting Jack; takes Krudsky prisoner; returns his army, Willow, Jack, Broomy, and Gibbles to the spirit world; and erases Fred, Daphne, and Velma's memories to keep his world safe, though he allows Shaggy and Scooby to keep theirs since they proved their courage.

Voice cast
The cast for the movie is shown below:
 * Frank Welker - Fred, Afterworld Express Conductor and Scooby-Doo
 * Casey Kasem - Shaggy
 * Mindy Cohn - Velma
 * Grey DeLisle - Daphne, Cat Witch and Honeybee
 * Hayden Panettiere - Fairy Princess Willow
 * Wayne Knight - The Amazing Krudsky
 * Wallace Shawn - Mr. Gibbles
 * Jay Leno - Jack-O'-Lantern
 * Tim Curry - Goblin King, Werewolf
 * Jim Belushi - Glob
 * Larry Joe Campbell - Glum
 * Lauren Bacall - Grand Witch
 * Thom Adcox - Sparkplug
 * Russi Taylor - Owl Witch and Tiddlywink

Original Songs

 * "Who's at the Door?" - Sung by Wallace Shawn
 * "Bump in the Night" - Sung by the Halloween Monsters
 * "Goblin Oogie Boogie" - Sung by Jim Belushi