Blue Mitchell travels from Nebraska to a racecourse in New York with a promising Thoroughbred colt sold by his boss, Con Norris, to August Belmont, Jr. Blue is asked to stay at the track while the colt settles, and his life is changed forever; he meets Willie Simms, an African American jockey of high character and skill, and he also finds his son from a previous brief alliance. Together Blue and Willie fight against those who would stop the colt from running, and encounter the underground of horse-racing in the year 1900.