In Los Angeles, two criminals Al Barkis [Edward Binns] and Pete Monty [Lee Van Cleef] attempt to hotwire a car inside a crowded car lot, while Vickie Webb [Joan Vohs] bids farewell to Jack Hartrampf, a married undertaker [Porter Hall], in a nearby apartment building. A tense confrontation erupts when Kellogg, a sharp police officer [Barry Kelley], tries to arrest Monty inside the vehicle, but Barkis shoots him in the chaos. As the getaway car zips away, Hartrampf races to Kellogg’s aid and is pulled into the city’s thicket of investigations. He is brought to police headquarters for questioning, yet he remains intent on shielding his personal life, reluctant to testify lest his affair become public knowledge.
Captain Barnaby [Edward G. Robinson] strides into his office, where his secretary Ginny [K.T. Stevens] delivers the grim news that Kellogg is in critical condition. In a parallel thread, Miss Easton [Christine White] arrives with a troubling concern: her mother is being targeted by an overseas fake count in a marriage scheme. Barnaby emphasizes that he needs more evidence before moving forward and assigns Sgt. Atkinson to dig into the case. In the hall, he encounters Frankie Pierce [Jay Adler], a parolee who insists Barkis is planning a bank robbery, laying the groundwork for further tension between law and crime.
Inside the interrogation room, Barnaby pleads with Hartrampf to testify about the shooting, but Hartrampf stands firm. A police lineup follows, and Barnaby is handed Frankie’s criminal record, prompting him to task Lt. Chisolm [Lewis Martin] with the investigative work ahead; meanwhile, Kellogg succumbs to his injuries. In a warehouse nearby, Barkis and his crew move forward, awaiting Dutch, who has just been detained for the lineup and is unknowingly delayed. Dutch [Charles Tannen] is released and arrives to warn the group that Kellogg is dead, complicating their scheme.
Back at the police station, Barnaby informs bank president Schaefer [Mack Williams] of the impending robbery and lays plans for a strategic trap. When Dwight Foreman arrives—an attorney who has ties to one of the alleged players—Hartrampf reiterates that he did not see the criminals the night in question due to darkness and movement around the apartment building. Barnaby then learns that Mona Ross, who runs an escort agency, may cooperate if two of her workers are released, and he agrees to the condition, hoping to maneuver the investigation forward. Elsewhere, Alfredo Di Nova, the overseas “Count,” is detained and shown to have committed identity fraud, given the option to depart town to avoid charges.
With the bank heist looming, Barkis and his accomplices press toward the bank as Chisolm and his undercover officers exchange fire with them. Dutch and another robber perish in the exchange, while Barkis wounds Lt. Chisolm and abducts Carol Lawson [Mary Ellen Kay], a bank teller, before escaping. In the wake of the shootout, Hartrampf faces a brief return to custody before being released again, though a later arrest is falsely attributed to him for drunkenness and disorderly conduct. In a tense exchange, Barnaby phones Mona to force information from her, using the leverage of her operation to squeeze out leads.
Mona arrives to reveal that one of her girls, Dolores, has been seeing Marty Kusalich [Adam Williams], a member of Barkis’s circle, who is staying at Dolores’s apartment. Two officers promptly arrest Marty, and during interrogation he claims no direct knowledge of the attempted robbery. Ballistic tests confirm that Barkis fired the shot that felled Kellogg, which leads Barnaby to a calculated strategy: pin Marty to the crime. Hartrampf is instructed to identify Marty and is released from custody to do so. Under pressure, Marty confesses that Barkis and Monte were the true culprits and discloses the warehouse location.
On the run, Pete Monty steals a boat to head toward the warehouse, where Barkis is holding Carol hostage. Carol makes a last-ditch attempt to escape, but her glasses fall away in the struggle, exposing her vulnerability. Detective Lacey [Harlan Warde] arrives to launch a rescue and shoots Barkis, bringing the immediate threat to an end. Monte is arrested soon after, and Barnaby arrives on the scene to confirm the night’s chaotic developments. As the wheels of justice grind on, Miss Easton phones her mother to report that she and her daughter are safe, closing this fraught chapter with a fragile sense of resolution.
