When a colleague mysteriously disappears off the coast of Amity Island, Mat Hooper leads a team of marine biologists to investigate what happened. Accompanying him is Mike Brody, the son of Amity's legendary police chief, Martin Brody. Both Mat and Mike have reasons for returning to Amity Island-personal reasons. Suspecting that another great white shark is responsible for the disappearance, the team soon realizes that is not the case. In the end, they discover astonishing revelations that will prove earlier speculations about the great white and sharks in general to be wrong.