In 1877, thieves Ace Beaudry, Bronco Dawson and Bull Stanley head West together after having each been betrayed by a woman. They come across a wagon train bound for the town of Custer, where hundreds of people are gathering for a land rush in the Dakotas, which President Ulysses S. Grant has opened to settlers thanks to a treaty with the Sioux Indians. After the three rogues ride off, they spy a lone wagon with a tempting string of thoroughbreds. Before they can steal the horses, however, the wagon is attacked by a gang led by Layne Hunter, a shifty saloon owner from Custer. The trio chase off the gang, and as they are about to abscond with the horses, they find pretty Lee Carleton, whose father was killed in the attack.