These are two early designs of Scooby, the one on the right looking more realistic and the one on the left looking more cartoony.
Seeing that Scooby-Doo (2002) was in development since the mid-90s under Universal but due to the Turner/Time Warner merger, the film was put under the Warner Bros.. banner and went through some changes in tone, plot, and even rating.Examples
- Development of the film dated back to the mid-1990s when Turner Pictures was being setup; Kevin Smith was at one point linked to the project
before Turner and Time Warner merged. - Jim Carrey was originally cast as Shaggy, while Lochlyn Munro auditioned.
- Jennifer Aniston and Jennifer Love Hewitt were considered for the part of Daphne Blake before Sarah Michelle Gellar was cast.
- Carla Gugino, Alyssa Milano and Christina Ricci were considered for Velma Dinkley before the casting of Linda Cardellini.
- Anthony Anderson was considered to play the Voodoo Maestro but had schedule conflicts with Down and Under.
- Weezer was asked to make appearances as actors, but rejected the offer.
- The original script was more faithful to the series and acted as a prequel story, explaining how the gang came together:
- The original script and the final film don't have much in common, other than a darker and higher stakes story than the series with an end of the world scenario, a character arc with a love interest unintentionally coming between Shaggy and Scooby (though the original script had her as more of a goth/grunge girl who shared Shaggy's passion for food as opposed to the Mary Jane character in the final movie), and risque humor with jokes about the old rumors that Shaggy was a pothead, hinting Mr. Wickles was a transvestite, and Scooby would have called the dogcatcher an 'rasshole'. Ironically, it ended up having more in common with the 2009 direct-to-DVD prequel film, Scooby-Doo! The Mystery Begins.
- The gang were originally meant to be enrolled in a college that had a newly instated 'No Dogs Allowed' rule that brought in a sadistic dogcatcher, forcing Shaggy to hide Scooby.
- Daphne would have been an aspiring reporter for the school's newspaper who was danger prone as she was in the series and is invited to attend and write about a part at the old Kingston Mansion (a call back to the classic series episode "What The Hex Going On?") on campus grounds but her roommate Velma comes with her due to a power outage and would meet Shaggy and Scooby, who were delivering pizzas, at the party.
- The party would have been broken up by the ghost that was rumored to haunt the place, but a series of events leads Scooby to knocking the ghost down and Velma unmasks him to be none other than Fred, who was doing it as a House Initiation Dare. The now five members of the gang would have been left in the mansion where the plot would take off and be attacked by the Ghost of Elias Kingston and they'd stumble into the film's mystery.
- There was also going to be a more serious romance arc between Daphne and Fred, who initially dislike each other but come to care deeply for one another, especially when Daphne discovered Fred is homeless and lives in what becomes the Mystery Machine.
- Other characters from the show such as Mr. Wickles and Old Hank would have appeared along with other Hanna-Barbera properties making cameos, such as Josie and the Pussycats appearing as a band at the party, an inanimate Speedbuggy in a parking lot, The Jetsons playing on TV, and William Hanna and Joseph Barbera themselves were also intended to make cameos at the end as the presidents of the university, praising Mystery Inc. for saving the school.
- Hadley Kay was going to voice Scooby, reprising his role from Johnny Bravo before he was replaced by Neil Fanning.
- Scrappy wasn't supposed to appear in the movie at all (not even being ditched by Scooby and the gang as part of the backstory), though James Gunn's original draft does have the U.S. Coast Guard threaten to put Scooby to sleep, with Shaggy adding, "Like what happened to Scrappy.". The main villain was instead supposed to be Old Man Smithers, the Luna Ghost from the beginning of the movie, living up to his vow of revenge; this is why the Luna Ghost's shadow is so prominent on the posters, home releases, and promo materials.
- A full-sized stand-in puppet of Scooby◊ was built by Jim Henson's Creature Shop for the film but it ultimately went unused and Scooby became a CG character instead.
