In the New England beach town of Amity Island, a young woman, Chrissie Watkins, goes skinny dipping in the ocean one evening during a beachside party. While she is treading water, an unseen force attacks her and pulls her under the water. The next day, her partial remains are found on shore. After the medical examiner concludes she was the victim of a shark attack, police chief Martin Brody decides to close the beaches, but Mayor Larry Vaughn persuades him to reconsider, fearing that the town's summer economy will be ruined. The coroner tentatively concurs with the mayor's theory that Chrissie was killed in a boating accident, and Brody reluctantly accepts their conclusion until the shark kills a young boy, Alex Kintner, in front of a crowded beach. A bounty is placed on the shark, causing an amateur shark-hunting frenzy, and eccentric and roughened local professional shark fisherman Quint offers his services for $10,000. Meanwhile, consulting oceanographer Matt Hooper examines Chrissie's remains, confirming that an abnormally large shark killed her.
