加州海岸一直都存在着两只巨大史前海洋生物,他们为了取得海洋的霸主地位而争斗了数百年,直到有一天他们被冰河所冻结。近年来,随着气温的升高,这两只史前生物又复活了,他们在海洋中依然为所欲为,人类的生存受到了威胁,人类必须要解决这样的危机,一场人与史前生物的惨烈争斗开始了。A huge iceberg calves that holds a megalodon (mega shark) and a giant octopus frozen inside it. Deployment of a LFAS (low frequency automatic sonar) unit causes it to shatter. The two behemoths thaw and return to life. The shark terrorizes the California coast while the octopus creates havoc things near Japan. A group of three oceanographers put together a plan to draw the beasts into a trap with pheromones.