Chinatown (1974)

In 1937 Los Angeles, private investigator Jake Gittes is hired by a woman claiming to be Evelyn Mulwray to uncover whether her husband, the chief engineer at the Department of Water and Power, is having an affair. Gittes discovers Mr. Mulwray with a young woman, and the photos spark a scandal. Gittes then slowly uncovers a dark web of corruption involving water control, land grabs, and hidden family secrets, where nobody seems to be who they truly are.