After being taken prisoner by Crazy Knife and a band of Cheyenne warriors, Wild Bill Hickok's life is spared by Chief Black Kettle, but when he is set free, it is without his horse and his boots.
Calamity Jane, driving a stagecoach, gives Hickok a ride back to the fort, where Lt. Stiles of the Army seems indifferent to Hickok's warning that the Cheyenne are now armed with repeating rifles. At the saloon, where Wild Bill renews an acquaintance with old friend Buffalo Bill, he spots a gambler named Lattimer cheating at poker and deals with him accordingly.
Crazy Knife and his men take Calamity Jane captive, and Lattimer turns out to be the one supplying them with the rifles. Hickok manages to save Jane, who loves him, and the fort ends up with a new officer in command, General Custer.