In the French Riviera, a series of high-profile burglaries rattles the wealthy community. The modus operandi of the thief closely resembles the signature style of a famed retired cat burglar, John Robie, who has settled into a quiet life of seclusion tending to his vineyards. The French police, alert to the similarities in the crimes, immediately suspect Robie of returning to his old ways. However, Robie knows he's innocent and understands that the only way to prove his reformation is to catch the real thief himself. To preserve his carefully constructed new life, Robie embarks on a quest to clear his name.

Robie's pursuit leads him to the opulent world of the rich tourists vacationing on the coast. He strategically befriends a wealthy American heiress, Frances Stevens, and her mother, hoping to use their high-society connections to gather information. As he tries to flush out the copycat, Robie finds himself entangled in a game of deception and attraction. Amidst fireworks and lavish parties, he must navigate the complex web of suspicion and allure, maintaining his guise and engaging in a delicate dance with the heiress, who is more observant and involved than she initially seems.