In the 1930s, boxer Barney Ross wins the welterweight championship, then meets chorus girl Cathy Holland as he celebrates. Sam Pian, his trainer, learns that Barney placed a $10,000 bet on himself to win the fight. Cathy, a single mom of a young girl, Noreen, gets to know Barney, but is unaware of his gambling habit. When he loses to Henry Armstrong, he owes thousands to a bookie named Big Ralph and is forced to work in Ralph's bar to pay off the debt.