When the aunt of Edna Wallace (Jean Wallace) is murdered, Inspector Jules Maigret (Charles Laughton) is brought into the case. Initial suspicion is thrown on a knife sharpener (Burgess Meredith), but Maigret soon takes notice of a student, Johann Radek (Franchot Tone), who keeps goading the police. Unfortunately, there is no evidence against Radek. The psychological games between Maigret and Radek escalate as the police narrow in on the killer, leading to a harrowing chase across Paris.