Tim Curry (Goblin King and Werewolf Bouncer) voiced Ben Ravencroft in Scooby-Doo and the Witch's Ghost (1999). He was offered the role of Emile Mondavarious in the first live action Scooby-Doo (2002), but turned it down because the movie featured Scrappy Doo, his least favorite character.
This is the first Scooby-Doo animated movie to be made without co-creator Joseph Barbera, who died on December 18, 2006.
Most of the ghouls and monsters in the tavern are identical to the disguises used by numerous villains-of-the-week that Mystery Inc. met between 1969 and 1984. Ironically, their lookalikes in this movie are mostly nice people, despite being real monsters.
Mystery Inc.'s hometown is confirmed as Coolsville on the carnival sign.
Wallace Shawn (Mr. Gibbles) plays the regular character Rex in the Toy Story franchise. Wayne Knight (The Amazing Krudsky) played The Collector in Toy Story 2 (1999) and Emperor Zurg in the Buzz Lightyear spin-off series.