In the year 1987, 17 people were killed by humanoid creatures called Aquanoids. These sea creatures seem to appear randomly and in the year 2003 return to Babylon Bay. The heroine of the story, Vanessa, sees the creatures and warns the town of the imminent danger. Vanessa's mother was one of the individuals killed in the first wave of attacks sixteen years ago. But the town's mayor, in an effort to acquire a major land deal for a new mall, tries to disguise the attacks as boating accidents.