Movie Story : Scoob tells the origin story of Scooby-Doo and Shaggy, showing how the lifelong friends first met and teamed up with young detectives Fred, Velma, and Daphne to form Mystery Inc. Years and hundreds of solved cases later, the gang faces its toughest challenge when a villainous scheme threatens to unleash the ghost dog Cerberus on the world. As they race to halt a global "dogpocalypse," Scooby discovers a secret legacy and a destiny far bigger than anyone expected.