Scooby Doo and the Mystery youth, Inc. have returned. Velma discovers that he has inherited cursed castle of his great-great-uncle Dr. Von Dinkenstein in Transylvania town in Pennsylvania. When Velma goes with her friends to see their heritage, the castle ghost gives a warning: they blow away the mysteries. The team must solve the mystery of who this time is personal. Who is responsible for Dinkenstein Von monster? What family secret hiding Velma? Fred will recover from the loss of his beloved cars? Does any snack will remain untouched by the enormous appetite Shaggy and Scooby’s?