Ignoring the advice of his attorney, Arthur Brennan, gambling ring boss Jeffrey Hilton continues to interfere with racketeer Oney Kessel's gambling operations. One night, Hilton is fired upon by one of Kessel's hitmen and dies in the arms of his fiancée, Vivian Saunders. Soon after the murder, Jeff's younger brother Joe, a quick-fisted World War II veteran, takes over Jeff's gambling enterprise. Joe's first order of business is to get the $5,000 that Donelli, one of Jeff's casino operators, owes the company. Later, Joe meets and falls instantly in love with Lynn Turner, an operator at one of his casino gaming tables. When word reaches Kessel that Joe is trying to cut into his business the same way Jeff did, he vows to stop him, and assigns Nichols, one of his new henchmen, to the task. Vivian, meanwhile, tries to charm Joe, but he rejects her attentions and begins dating Lynn. Joe continues to see Lynn, even though she is determined to reform him. One day, Vail, a mayoral candidate with reformer backers, threatens to close down Joe's casinos unless Joe quits the business. When Vail tells Joe that his casinos are illegally employing under-aged women, Joe vows to find the ones under twenty-one and fire them. After firing Lynn, who is nineteen years old, Joe tries to help her by delivering her to her father. Lynn's father, however, is an uncaring alcoholic and refuses to take her in. Later, while dining with Lynn at a nightclub, Joe tells her that he took over his brother's business to exact revenge against civilians who made great profits while he was fighting in the war. In the hopes of preventing Vail from becoming mayor, Joe and Kessel call a truce and agree to support the candidate who is opposing Vail. Joe, however, inadvertently undermines his own plan when he loans money to his army pal, Sam Austin. Sam, a reformer, donates the money to Vail's campaign effort, and his donation results in Vail's victory. When Kessel learns that Vail has won the election with Joe's money, he believes that he has been double-crossed, and plans to kill Joe. Kessel shoots Joe and slightly wounds him, but the police arrive in time to arrest Kessel and his men. Joe eventually makes a full recovery, and although Vail has eliminated all gambling houses in his jurisdiction, Joe is happy to learn that Lynn will remain his sweetheart.