After wrapping up their latest mystery, Velma gets a call from her mother asking that she check on her younger sister Madelyn, who attends a college for magicians. The gang heads to the Whirlen Merlin Magic Academy, located in an old Irish castle. Once they reach the castle they meet the owner, Whirlen Merlin, along with his brother Marlon, who acts as cook and butler, and Crystal, Whirlen's former stage assistant. The gang learns that a giant griffin has been scaring away the students and staff.