In Scooby-Doo’s greatest adventure yet, see the never-before told story of how lifelong friends Scooby and Shaggy first met and how they joined forces with young detectives Fred, Velma, and Daphne to form the famous Mystery Inc. Now, with hundreds of cases solved, Scooby and the gang face their biggest, toughest mystery ever: an evil plot to unleash the ghost dog Cerberus upon the world. As they race to stop this global “dogpocalypse,” the gang discovers that Scooby has a secret legacy and an epic destiny greater than anyone ever imagined.
Wilbur the pig is scared of the end of the season, because he knows that come that time, he will end up on the dinner table. He hatches a plan with Charlotte, a spider that lives in his pen, to ensure that this will never happen.
Scooby, Shaggy and Scrappy Doo are on their way to a Miss Grimwood's Finishing School for Girls, where they have been hired as gym teachers. Once there, however, they find that it is actually a school for girl ghouls.
In this Halloween Special, Babs Bunny plays the part of host as she and the Tiny Toons gang spoof various popular horror movies and TV shows. Among the works parodied are "Night Gallery", "The Twilight Zone", "The Devil and Daniel Webster", "Frankenstein" and the "Abbott and Costello Meet..." films.