Ruh-roh! Fred's cousin, Jed, is nowhere to be found! His animatronic monsters have gone haywire and are attacking everyone in sight! It's up to Scooby-Doo and Mystery, Inc. to stop the creepy costumed creatures, unmask the mystery, and find Jed before it's too late. Could Jed be prime suspect? Zoinks! Get me a Scooby-Snack!