Upon Scooby's return to his home town, a demon circus comes to plague Doosberry. It's up to the gang to save the city from being taken over by the phantom three-ring villains.

The gang goes on Boris Kreepoff's TV show in hopes of finding one of the demons and they have their chest of demons stolen. In their search for the chest, they find both a demon and a villain trying to steal the chest for his own gain.