Mike Schultz is boxing as his manager Sal Cooper watches from the sidelines. Cooper tells Schultz to take a dive when mobster Martin gives the high sign. Schultz ignores it and knocks out his opponent. Afterward, Cooper visits Schultz in the locker room and warns him that Martin will take it out on him, but Schultz isn't worried. However, after Cooper leaves, hit man Luca Burnett comes in and disposes of Schultz.
Police Squad investigates but despite the fact Luca made Schultz's death look (vaguely) like a suicide, Ed and Frank aren't convinced. Ed is aware that there's corruption in boxing and has Frank go undercover. Frank needs a boxer that he can convince to go straight. He goes to Jim's Gym and looks up Buddy Briggs, a down-and-out boxer that Cooper owns. Buddy isn't interested, so Frank goes to Cooper and wins Buddy's contract in a poker game. When Cooper goes for his gun, Frank trumps him by drawing his own gun, but Cooper warns that Frank will never get a fight for Buddy.
At Police Squad, Ted discovers whiskers at the crime scene that can be traced to Luca, who works for Martin. Frank goes to see Buddy and his drunken girlfriend Mary, who has turned to drink because Buddy is a loser. Frank tells Buddy that he's his new manager and won't be throwing fights any more. Mary accuses Buddy of being a coward and walks out, and a disconsolate Buddy turns to Frank. Frank assures him that if he goes straight, he can get Mary back.
Next they have to get a fight with the Champ. Frank and Buddy go to the bar where he hangs out, and find Martin and Cooper having dinner together. Martin warns that Frank won't get Buddy a match, so Frank picks a fight with the Champ and Buddy decks him with one punch. The reporters play up the incident and the Champ agrees to the match.
On the night of the fight, Martin comes to the locker room and shows Buddy Mary's toaster: they have her and he either throws the fight in the 12th or Mary dies. Frank vows to find Mary and get her back there so Buddy can win the match and regain his pride.
Frank checks with Johnny the Snitch, who tells him that Luca is at Jim's Gym with Mary. Frank goes there and arrives just as Mary manages to cut her ropes. She runs for it and Luca grabs her, takes her hostage, and ducks into a steam room. Frank manages to find him and is forced to shoot him down.
At the ring, Martin continues to remind Buddy that he has Mary hostage. Buddy starts to go down as the Champ relentlessly pounds him… until Frank and Mary arrive. Inspired by the return of his girlfriend, Buddy takes the Champ down with one punch. Ed and the boys arrest Martin as he tries to make a run for it.
Later at Police Squad, Ed and Frank are relaxing as Martin is brought in for processing. He boasts that he'll beat the rap, but Frank tells him he'll be going to Statesville Prison, just like Sally Decker. Martin gets a chance to make a run for it but fails.