Martin Brody is the new police chief of Amity, an island resort town somewhere in New England. He has a wife named Ellen, and two sons named Michael and Sean. On a Summer morning, Brody is called to the beach, where the mangled body of Summer vacationer Chrissie Watkins has washed ashore. The medical examiner tells Brody that it could have been a shark that killed Watkins. Mayor Larry Vaughn, who is desperate to not lose the money that will be brought in by 4th of July tourists, wants Brody to say Watkins's death was caused by a motorboat propeller instead of a shark, because the thought of a shark in Amity's waters would drive tourists away from Amity. It looks like Vaughn is a mayor who puts money ahead of people's lives. Shark expert Matt Hooper believes Watkins was killed by a shark. Hooper is proven right a few days later, when Alex Kintner is killed by the shark that killed Watkins. Looking for the quickest solution, Vaughn tells all of the local fishermen to let him know if they see the shark. A shark hunter named Quint offers to find the shark and kill it, but Vaughn thinks Quint's price of $10,000 is too high. When a tiger shark is killed and hauled in by a couple of boaters, Vaughn hastily says that the shark crisis is over, but Hooper says the shark that's been killing people a huge great white shark is still in Amity's waters, but Vaughn leaves the beaches opened because all he cares about is the 4th of July tourist money. On the 4th of July, Vaughn encourages people to swim at the beach, and Hooper is proven right again when the shark kills a man, biting the man's leg off. Michael, who was in the water at the time of the attack, is taken to the hospital, where he's treated for shock after watching the shark kill the guy. Brody asks Vaughn to hire Quint to find the shark. Because his own kids were at that beach too, Vaughn agrees to hire Quint to find the shark. Quint, Hooper, and Brody are sent out to sea in Quint's boat, the Orca, ready to do whatever it takes to find the shark.