Robbie Amell (Fred), Hayley Kiyoko (Velma), Kate Melton (Daphne), Nick Palatas (Shaggy), Frank Welker (Scooby-Doo), Richard Moll (Elmer Uggins), Ted McGinley (Uncle Thorny), Alexandra Quinn (Twisting Girl), Carey Jones (Lake Monster Suit Performer), Jade Quon (Scooby Hip Hop Suit Performer), Luke Youngblood (Scooby Suit Performer), Nichelle Nichols (Senator), David Dedinsky (Tennis Player), Marion Ross (Hilda Trowburg), Beverly Sanders (Wanda Grubworth), Patrick Babbitt (Wolfman), Karee Higashi (Hawaiian Dance Girl #2), Michael Berryman (Zombie Head), David Joyner (Sinister Clown), Cherisse Ligot (Hawaiian Dance Girl #1), Alexandria Quinn (Twisting Girl), Brad Morris (Witch Doctor), Danielle E. Hawkins (Scooby Roller Disco Suit Performer), Jane Oshita (Scooby Hawaiian Dancer Suit Performer), Philip Albuquerque (Scooby Hip Hop Suit Performer), Mike Cochrane (Settler #1)