The gang takes a vacation to Hawaii where, unbeknownst to them, a nearby volcano is about to erupt thanks to an ancient amulet possessed by the evil Queen Medula. The descendant of Medusa, with her servant Kumo, plans to turn all of the investigating scientists to stone and sell them to the highest bidder, but Fangface, Fangpuss, and Puggsy overhear here scheme. The gang has to defeat Medula and rescue the scientists... without being turned to stone themselves.