A Californian housewife is terrified of having sex because of a past assault. When this phobia threatens to destroy her marriage, she takes refuge in a series of erotic fantasies about a masked man. But is it really all just a fantasy?

The staff and vacationers at a first-class resort on the island of Maui are beginning to mysteriously disappear. A biologist believes that an underwater earthquake has caused a giant and very hungry dormant prehistoric fish to be released from its slumber. The fish voraciously helps itself to a tourist buffet. Now it is open season for the local fishermen to find and kill the creature.