Singer-turned-boxer Andy 'Kid' Clave signs a contract with a shady promoter Joaquin Vargas. But Clave turns against Vargas when the promoter's thugs kill Clave's girlfriend when he thinks about backing out of the contract. While seeking a way to get revenge against Vargas, Clave learns that he has a blood clot in his head. But nothing will deter him from getting his revenge and making a shot at the title.

The life of boxer Jake LaMotta, whose violence and temper that led him to the top in the ring destroyed his life outside of it.