As he is driving cynical sports reporter Willie Wagonstatter to the Hollywood racetrack, where retired champion Gallant Man is attempting a comeback in the Gold Cup race, taxi driver Toby Gleeton relates the story of how he and Gallant Man's owner, Joe Grange, first met: On a rainy Christmas Eve in Hollywood, Toby offers a ride to Joe and his colt, then agrees to drive Ronnie, a soda clerk, to her apartment. The homeless Joe, who earlier that day quit his accounting job and bought the horse, persuades Ronnie to put the animal up for the night. Joe agrees to spend the evening under an awning, but after the colt almost destroys Ronnie's small apartment, she reluctantly allows Joe to sleep on her couch. Joe names the frisky colt Gallant Man and reveals to Ronnie that his longtime dream has been to raise a champion racehorse and "live his heart." Although Ronnie admits that she has been unlucky in love, she tells the soft-spoken Joe that he is an "awfully nice guy." Joe, in turn, is attracted to Ronnie, and a romance soon blossoms. Later, Joe, who is now working as a stablehand for John Ramsey, a horse owner and gambler, proposes to Ronnie, but she convinces him that they should wait until Gallant Man has run his first race. Joe has won over $700 in poker and racing bets, but Ronnie, worried about their financial future, encourages him to build a more secure nest egg. Sometime later, as Gallant Man is about to run in his first race, Joe instructs Toby, with whom he has become close friends, to bet Joe's $2,000 savings on Gallant Man, a longshot. Gallant Man wins, but as Toby had disobeyed Joe and bet on the favorite, the now-married Joe and Ronnie wind up broke. Despite the financial setback, Joe and Ronnie look forward to a happy future together and enjoy a modest honeymoon. However, a year later, on New Year's Eve, Ronnie chastises Joe, who now owns a stable of horses, for gambling too much and neglecting their marriage. Ronnie then reveals that she is pregnant, prompting Joe to vow to spend more time with her. Joe fails to keep his promise, however, and is absent when Ronnie gives birth to a son, Richard. When he finally shows up at the hospital, Joe apologizes to a depressed Ronnie, explaining that he was in the middle of a poker game, in which he won a house in Bel Air. Joe again pledges to spend more time at home, and Ronnie, impressed by her new dream house, forgives him. Two years later, however, Joe has not changed his ways, and after he reluctantly decides to retire the unbeaten Gallant Man, whose weight handicap has become dangerously heavy, Ronnie asks for a separation. Joe's other horses fail to make up for Gallant Man's absence, and Joe is nearly bankrupt when he allows Ramsey to goad him into making a $40,000 bet. After Joe loses the wager, Toby informs him that Richard has pneumonia. Joe rushes to Richard's bedside, and his presence helps the boy to recover. Later, the now-broke Joe moves to Florida and resumes his accounting career. Lonely, Ronnie visits Gallant Man at the stables and recalls how Joe's faith in the horse had so touched her. Upon hearing that Ronnie has entered Gallant Man in the Hollywood Gold Cup race, Joe rushes to Los Angeles and tries unsuccessfully to have the horse scratched from the field. Convinced that Gallant Man cannot win the $100,000 race, Joe angrily refuses to join Ronnie in the stands. Much to Joe's joyful amazement, Gallant Man charges from the back of the pack to win the race in the last seconds. At the stables later, Joe apologizes to Gallant Man for losing faith in him and tells Ronnie that he is ready to come home for good.