On a small island off the California coast it's the Fourth of July and tourists are washing up dead in Babylon Bay, once again! In 1987, rumor has it that mysterious sea creatures called Aquanoids were responsible for 17 vicious deaths. The Mayor dispelled the sightings as urban legend to protect the local tourist trade. Join environmental activist Vanessa DuMont as her fight to save the endangered abalone on Santa Clara Island turns into a fight of her life.

A group of college students decide to party at the abandoned chemical factory on the outskirts of town, unknowing that one of the former factory workers is still lurking about.