On a hot New York summer night, two men
chloroform ex-model Jean Dexter and drown her in her bathtub. When one of them gets conscience-stricken while drunk, the other kills him and throws his body into the
East River. Experienced
New York City Police Department detective Lt. Dan Muldoon and novice Det. Jimmy Halloran are assigned to the case. At the scene the medical examiner determines the “accidental” death had actually been murder. A pair of men's pajamas yields only the name “Philip Henderson” from her housekeeper, who reports that Dexter's hoard of expensive jewelry is missing. A bottle of sleeping pills leads Halloran to the doctor who prescribed them, Lawrence Stoneman. Ruth Morrison, a model friend of Jean's, is also located and questioned. At the precinct, Muldoon interrogates Frank Niles, Jean's ex-boyfriend, who claims only a business relationship with Jean and denies knowing Ruth, although the pair are actually engaged. He lies himself into becoming the prime murder suspect, but has an airtight alibi. Later, Muldoon deduces from the bruises on Jean's neck that she was killed by at least two men. The detectives learn that Niles has just sold an expensive cigarette case stolen from Stoneman, then purchased a one-way airline ticket to
Mexico City. They also discover that one of Jean's rings was stolen from the home of a Mrs. Hylton. At the matron's
Park Avenue apartment, the police learn that the ring actually belonged to her socialite daughter from a previous marriage, who, to their surprise, is Ruth Morrison. Finding that Ruth's engagement ring was stolen in a different robbery, Muldoon and Halloran take Ruth to Niles' apartment. There they interrupt someone attempting to chloroform him, who shoots his way down the fire escape and disappears onto an elevated train. When questioned about the stolen jewelry, Niles claims he had gotten everything as gifts from Jean. Realizing she is engaged to a pathological liar and a criminal, Ruth slaps him. Niles is then arrested for the jewel thefts, but remains silent regarding his attacker. The body of small-time jewel thief Peter Backalis is found in the East River, having been murdered within hours of Jean; Halloran suspects the two killings are connected. Muldoon, although skeptical, lets Halloran pursue the lead and assigns two veteran detectives already on the case to assist. Through considerable legwork they learn that Backalis' last known accomplice had been Willie Garzah, a former wrestler who plays the harmonica. While Halloran and his team canvass the
Lower East Side with an old publicity photograph of him, Muldoon demands Niles identify Jean's mystery boyfriend. He reveals that "Henderson" is the same Dr. Stoneman, a married society physician. At Stoneman's office, Muldoon uses Niles to trap the doctor into implicating himself. Stoneman confesses that he became obsessed with Jean only to learn that she and Niles were using him in order to rob his wealthy friends. Niles then admits to planning the thefts, but says Backalis and Garzah did the jobs; denied a larger cut, they killed Jean. On his own, Halloran locates Garzah and unsuccessfully tries to take him into custody, but Garzah knocks him out and flees. As the police descend on the neighborhood to organize a
dragnet, Garzah attempts to blend into the crowd, but becomes paranoid and shoots a
guide dog when it bites him at the
Williamsburg Bridge, within earshot of the police's rallying point. The police chase Garzah along the bridge's footpaths and seal off both ends, forcing him to climb one of the towers. Injured by a police bullet and cornered, Garzah shoots at the police, who return fire, fatally wounding him before he plummets off the tower. The next day, the people involved in the case live with the aftermath. In
Times Square, a trashman sweeps a gutter of yesterday's newspapers, and with them the Jean Dexter case. A concluding voiceover states, "There are eight million stories in the naked city. This has been one of them." ==Cast==