Dr. Robert Bolton and his partner Dr. Luther Paradigm create a machine, known as the "gene-slammer", capable of changing aquatic animals into anthropomorphic hybrids. Attempting to prevent Paradigm from using the machine for personal gain, Bolton is transformed into an unseen monstrosity and subsequently Bolton's four sons are lured into a trap and transformed into man-sharks. When Dr. Paradigm captures their friend Bends, the resulting "Street Sharks" dive headfirst into a rip-roaring rescue mission.