The township of Cheyenne Falls, Dakota Territory, 1875. A ranch owner and friend of Ulysses Grant asks the President for some help with the lawlessness going on in the territory. The President sends United States Marshal, James Vaughn, to investigate the matter.
Vaughn arrives and finds the township and the territory to be overrun with road agents, troublemakers, loose women, unhappy Indians a corrupt Sheriff and another ranch owner bent on running things his way.
Vaughn begins the cleanup of the town with the help of a young deputy sent to him by his friend Virgil Earp and an ex-janitor hired by the previous sheriff.