A mysterious blue man-beast called the Heap Creature has been destroying computer inventions all over the city before their unveiling. The gang is invited to stay with Professor Boyd who has yet to have his invention destroyed. Only one other professor hasn't been attacked by the Heap Creature: Professor Arnos, who was fired from the university years ago for performing unauthorized experiments. Fangface and the gang set a trap to try to prevent the Heap from attacking Professor Boyd's home. Fangface eats Puggsy, and while Biff and Kim try to get him free, the Heap escapes with Professor Boyd in tow. The gang follows the Heap's footprints in hopes of solving the mystery and saving the professor in time. The Heap reveals himself to Boyd as Professor Arnos, who has created a metamorphosis ray that can alter a human's appearance. Arnos wants revenge on the scientists who laughed at him, and the gang has to find a way to stop him.