Superman stops Larry Trent, former heavyweight champion of the world, from committing suicide by jumping off a bridge. He learns that Trent had been betrayed by his manager, who conspired with a gangster to drug him, in order to clean up on all the bets for Trent. Superman vows to restore to Trent his lost title. He disguises himself as Trent, battling his way to the top, meanwhile training Trent for his own comeback. When the championship fight comes, Superman switches with Trent, who wins his own fight, taking back the title. At the same time, Superman sees the crooked manager and gangster taken care of.