A murder witness identifies Dan as the killer and his bizarre behavior hinders Sam and Jim's attempts to clear him. Dan is trying to protect his crippled ex-partner Tony and Tony's daughter Ani, who are being blackmailed.
A frightened builder is killed in an explosion after talking to Stone and Briggs, and Sam tries to shake Maitland a building inspector in the pocket of racket boss Koster.
A war hero, who saved Sam's life in Korea, thinks the smugglers he's aiding are trafficking uncut diamonds. What they're really smuggling is pure heroin and Sam must work to extricate his friend from the scheme.
Sam is suspicious when deposed syndicate leader Harry Majeski offers to testify against his successor, Vic Durrant, and is then abducted from police custody during an ambush.
Frightened victims of high society burglars give false information to Sam and Jim, hindering their investigation. When the crooks pursue the victim's daughter at Marineland, the Squad must race to the rescue.
Langley thwarts all attempts to investigate Betty Barnes's death, even going so far as to nearly kill Sam and Dan, so Sam comes up with a new plan which involves the tycoon's fear of germs.
Sam refuses to believe it was an accident after the beautiful young girlfriend of powerful millionaire Adam Langley is found dead in his swimming pool.
Jim is wounded and left for dead in the city's sewer system while chasing a burglary suspect, and Sam puts pressure on the crook, Layton, to try and find his injured partner.
Stone's attempts to bust paramilitary leader Flagg are hampered by the man's embittered former second-in-command, who wants revenge for being thrown out of the group.
Jim's girlfriend Cloris introduces him to a man she says is her brother. He's really her ex-husband convict who's shaking her down for money to get out of town. He steals Jim's gun and badge and uses them to commit murder.
During a spell of excruciatingly hot weather, Stone and Briggs turn up the heat to find two murderous muggers. Unbeknownst to Sam, they've forced their way into the home of Albie Froehlich, one of Sam's top snitches.
Captain Nye is critically wounded in an elevator, Stone and Briggs must search for a well-dressed hit man before he makes a second attempt on the Captain's life.
An argument leads to a senseless murder in an all-night diner, putting the officers on a trail of two thrill-seeking punks who are now plotting an extortion scheme against a woman.
A deluded Korean War Veteran breaks out of an Army Hospital and stalks a beautiful housewife, whom he believes is a USO dancer he fell in love with during the war.
An Internal Affairs investigation on fellow detective Bill Ehlers is done when he is suspected of stealing money recovered from a bank robbery. He refuses help from his fellow officers and sets out to find the robbers himself.
A death-row inmate Joe Caslin points out the similarity between a current crime and his conviction, which in turn sets about a turn of events to save Joe.
Detective Jim Briggs breaks up a parking lot quarrel between a valet and a hot-shot lawyer who offers money and is arrested for attempted bribery. When Gorman fakes an injury and accuses the detective of police brutality, Sgt. Stone puts his own badge on the line to help him.