In the tranquil fishing village of Noyo on the west coast of the USA, horror arrives: Fearsome underwater monsters attack the unsuspecting inhabitants, kill the men and rape the women. The brave fisherman Jim Hill and biologist Dr. Susan Drake take up the fight against the creatures, which turn out to be genetically mutated fish. At the annual salmon festival in Noyo, the fish monsters then attack the city. Can Jim save his hometown from the worst?