The ex-wrestler rabbit punches the rookie detective, momentarily knocking him unconscious. Meanwhile, Halloran finally locates Garzah and, pretending that Backalis is in the hospital, tries to trick Garzah into accompanying him, but Garzah (knowing he killed Backalis) sees through the ruse. Halloran and Muldoon, using different approaches, have come up with the same killer. Niles then confesses that Garzah killed Jean and Backalis. At Stoneman's office, Muldoon uses Niles to trap the married, respectable physician into confessing that he fell in love with Jean, only to learn that she and Niles were using him in order to rob his society friends. While Halloran and his team canvass the Lower East Side of New York using an old publicity photograph of Garzah, Muldoon compels Niles to identify Jean's mystery boyfriend. Through further methodical but tedious investigation, Halloran discovers that Backalis's accomplice on a jewelry store burglary was Willie Garzah, a former wrestler who plays the harmonica. Muldoon, although skeptical, lets him pursue the lead and assigns two veteran detectives on the squad to help Halloran with the legwork. Halloran learns that a body recovered from the East River, is that of small-time burglar Peter Backalis, who died within hours of the Dexter murder, and Halloran believes the two incidents are connected.
Niles is then arrested for the jewel thefts, but the murder case remains open. Ruth realizes she is engaged to a swindler and slaps him. When questioned about the stolen jewelry, Niles claims that they were all presents from Jean, which reveals his true relationship with her, much to Ruth's chagrin. The killer takes a shot at the cops and escapes down the fire escape onto the nearby elevated train. Learning that Ruth's engagement ring is also stolen property, and that she is engaged to Niles, Muldoon and Halloran take Ruth to Niles' apartment, where they coincidentally interrupt someone trying to murder him. Hylton's Park Avenue apartment, the police learn that the ring actually belonged to her socialite daughter, who, to their surprise, turns out to be Ruth Morrison (having retained the name of Mrs. They also discover that one of Jean's rings was stolen from the home of a wealthy Mrs. The next morning, the detectives learn that Niles sold a gold cigarette case stolen from Stoneman, then purchased a one-way airline ticket to Mexico. Batory, from whom Jean was estranged, arrive in New York to formally identify the body and tell the detectives that they have no knowledge of Jean's acquaintances.
Later, Muldoon deduces from the bruises on Jean's neck that she was killed by at least two men. Because of his lies, Niles becomes the prime suspect. Back at the police station, Muldoon questions Frank Niles, Jean's ex-boyfriend, who lies about everything, claiming only a business relationship with Jean and denying knowing Ruth. Halloran questions the doctor who prescribed the pills, Lawrence Stoneman, and Ruth Morrison, another model and Jean's friend. They also discover a bottle of sleeping pills and her address book. At the scene, the police interrogate Martha Swenson, Jean's housekeeper, about Jean's boyfriends, and she tells them about a "Mr. Muldoon has been a homicide cop for 22 years, Halloran for three months. Jimmy Halloran, are assigned to Jean's case, which the medical examination has determined was murder. Dan Muldoon and his young associate, Det. When one of the murderers gets conscience-stricken while drunk, the other kills him and throws his body into the East River. In the late hours of a hot New York summer night, a pair of men subdue and kill Jean Dexter, an ex-model, by knocking her out with chloroform and drowning her in her bathtub.