Real estate developer Jake Berman hires private investigator and war veteran Jake Gittes for some run-of-the-mill matrimonial work. After Berman shoots his wife's lover, who happens to be his business partner, Gittes is drawn into a web of conspiracy and deceit involving the oil reserves beneath Los Angeles. While investigating, Gittes hears a voice from his past that causes him to revisit a traumatic case in Chinatown.

After five years in prison for insurance fraud the sailor Lanarsky is released. Together with his buddy Bone he gets a job as seamen on board the yacht owned by the wife of his insurance fraud-partner Michael Reddick. Lanarsky has a question to his former partner who he thinks tried to cheat him. But Michael Reddich himself has another insurance plan ready where he will kill everybody on board the yacht, blow it up and then claim the life-insurance for his wife. But Lanarsky and the wife Lee escape and follow Michael to the nearby Cayman Island where the final showdown takes place.