led to the resort's haunted house ride, where Fred and Velma encounter a schoolroom that educates inhuman creatures about human culture, while Daphne discovers a pyramid-shaped artifact called the Daemon Ritus. Fred, Velma and Mondavarious are kidnapped and later possessed by the island's demons. Mary Jane calls the Coast Guard for help, but they don't arrive. The next day, after trying and failing to tell Shaggy that Mary Jane is a demon in disguise, Scooby goes missing as well; Zarkos steals back the Daemon Ritus from Daphne, who is also captured and possessed. Shaggy goes in search of his friends and finds a vat of protoplasm containing the souls of those possessed. He finds and frees the souls of Daphne, Fred and Velma, who discovers sunlight destroys the demons. A voodoo priest who lives on the island informs the gang the demons are to perform their "Darpokalypse" Ritual, which will see them rule the world for ten thousand years if a pure soul is sacrificed in the Daemon Ritus. The gang realizes that the pure soul is Scooby, whom Mondavarious brought to Spooky Island for this very reason. Fred, Daphne, and Velma finally realizes their mistake, they decide to put aside their differences and work together with Shaggy to save Scooby. The gang infiltrate the ritual, where Mondavarious is foiled in sacrificing Scooby's soul by Shaggy. Mondavarious is revealed to be a robot controlled by Scooby's estranged nephew Scrappy-Doo, whom the gang abandoned long ago after his increasingly power-hungry and egomaniacal nature got out of control. Absorbing the tourists' souls, Scrappy transforms into a huge monster and tries to kill the gang. Daphne kills the demons by reflecting sunlight through a skull-shaped disco ball and knocks Zarkos into the vat, returning most of the other souls to their bodies. Shaggy frees the rest of the souls and finds the real Mondavarious imprisoned, having been captured by Scrappy so he could pose as his double. Scrappy and his henchmen are all arrested and Mystery, Inc. reunites. Cast Freddie Prinze Jr. as Fred Jones Sarah Michelle Gellar as Daphne Blake Matthew Lillard as Norville "Shaggy" Rogers Linda Cardellini as Velma Dinkley Rowan Atkinson as Emile Mondavarious / Fake Emile Mondavarious Miguel A. Nunez Jr. as Voodoo Maestro Isla Fisher as Mary Jane Neil Fanning voices the titular character, Scooby-Doo. Scott Innes reprises his role as the voice of Scrappy-Doo and J.P. Manoux