At the start of the heavyweight championship boxing match, the fans boo at title holder Coke Mason, as his estranged wife Rose bitterly recalls the circumstances that brought them to this day: Coke works as a miner and Rose as a store clerk in Coal Town, Pennsylvania. Coke saves all his money so they can marry and open a radio store to escape their hated jobs and the stifling small town. When fellow miner Alex repeatedly picks fights with Coke, Coke's older brother George encourages the two to box. Alex dominates the match until the ordinarily composed Coke becomes enraged and beats him viciously. Frightened by his own brutality, Coke vows never to fight again. Days later, Alex uses too much dynamite to blast a hole in the mine and the roof collapses. George heads the rescue effort and works throughout the night to rescue the men. Later, at the hospital, after she overhears George urging Coke to give up low-paying, dangerous mining work for boxing, Rose convinces Coke that if he boxes for only one year they will have enough money to open their shop. Coke begins to train with his pal, Tommy "Speed" O'Keefe. During his first fight, Coke again is foundering until he becomes incensed and pummels his opponent, causing the crowd to boo him for what they see as dirty fighting. Over the next few months, Coke continues to win in the same manner and the crowds grow to despise him. Max Watkins, an esteemed sports writer, reports that Coke is murderous and should not be allowed to fight. Coke despairs over the crowd's animosity, but as the money pours in, Rose and George encourage him to keep fighting until one day they watch as he is badly beaten in a fight with champion Jackie Savella. Realizing that he is not a skilled fighter, only a brutal one, they urge him to quit, but Coke has grown cold and insists on proving to the fans that he is a champ. Soon, while Speed begins to fight his own matches and gains a reputation as a beloved, clean fighter, Coke grows more despised and bitter. At a party, George and Herb Riley, Savella's manager, recognize that during the upcoming Mason-Savella fight, the boxers will destroy each other, either because of Savella's skill or Coke's rage. Hoping to avoid this, George convinces Rose to pay all their savings to Riley in exchange for Savella taking a dive. After Coke wins the fight, however, Max is suspicious and calls for an investigation. The hearing convinces Coke that Rose and George have no faith in his skill, and he punches both Rose and Speed and storms out. Weeks later, Coke, still estranged from Rose and George, tells Max that he is the only person he can trust. Coke reveals that as a child, he was always taunted and forced to fight for his life, an experience he cannot now shake. Max agrees to manage him but instructs Coke that he must learn to take humiliation without wanting to kill his opponent. Soon, Coke wins the heavyweight championship, and the only fighter he has yet to compete against is Speed, who has become a close contender for the title. When Rose learns that the two are scheduled to fight, she berates Max, who explains to her that this fight will be Coke's ultimate challenge and may force him to grow up. Back in the present, Rose watches nervously as the fight begins. During the match, the fans and reporters stir when they realize that Coke is not fighting dirty. The competition is fierce, but in the last round Speed wins. George rushes to Coke's side, and as he helps the fighter leave the ring, the crowd slowly rises to its feet in a standing ovation. When Rose runs to Coke, he embraces her while the fans cheer.