The greatest killing machine is three times as deadly when a mutated great white shark with three heads originating from the Great Pacific garbage patch eats its way through an island research facility. As the survivors escape, the shark finds a party boat, forcing the passengers to fight the deadly predator using anything they could find. As the shark chomps its way from one end of the boat to the other, survivors from the research facility arrive and attempt to help the passengers escape. They escape, however is´s only short lived as the shark is hot on their trail .At one point the 3-headed sharks middle head is chopped off, only to find that it grows three more heads in its place. The survivors head off the new island with new boats. As one of the boats is destroyed, killing the remain