Jim poses as an inside man at the baseball stadium's payroll window to nail a gang of thieves disguised as security guards.

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.

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.

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.

After Jim shoots and kills an armed robber, the man's father retaliates by kidnapping Jim's father Dan.

Sam refuses to believe it, but all the evidence in two murders points to his former partner, now a hot-shot Lieutenant.