A kind-hearted Native American adopts a homeless, orphaned Chinese boy who has only a horse to his name. The boy's new parents mate his horse with their mare and the resulting filly proves to be fast. They nearly lose the filly, but manage to get her out of the clutches of a dishonest horse manager. They then breed her. On the day she foals, they find oil upon the land and they name the colt "Black Gold." Together father and adopted son raise the horse with the hope of entering it in the Kentucky Derby. Unfortunately, by this time, the father is an old man and just before he dies, he makes the boy promise to run the horse in the Big Race.