Heavyweight Champion Joe Palooka and his friend, Humphrey Pennyworth, find a slain gambler near Joe's training camp. The escaping killers fire at them, but neither is hit. District Attorney Michael Brogdon fails to prosecute the case when the body can't be found. A gangster contacts Knobby Walsh, Joe's manager, and tells him to have his fighter throw his upcoming title-defense. Knobby refuses and is kidnapped in order to force Joe to throw the fight. And, for insurance, Joe is doped in the ring.