An American talks a retired French crook into robbing a bank, but kidnappers demand the loot as ransom.

In the heart of Paris, a restaurateur's mundane life is disrupted by the arrival of his ex-wife's daughter, who claims to be in need after her mother's death. After marrying her, tensions rise when she becomes involved with a young student, leading to betrayal and murder. As secrets unfold, he uncovers the truth about her past and her manipulative nature.

Four women were murdered, each was knifed and, though they had their clothes torn, they weren't molested. As the famed police inspector Jules Maigret pieces the clues together, he comes to realize that for the elusive man that he suspects to be unmasked, he has to set him a trap.