一艘在海上航行的船只,被一种变异的双头鲨鱼袭击。幸存者游到了一座荒岛上寻求庇护,但是噩梦远没有结束。Terror takes a ghastly form when a gigantic two-headed shark sinks a ship full of students, and the survivors wash up on a tiny atoll. But just when the kids think they're safe, a tsunami sweeps them back into the deep to face the twin jaws anew.