Bronco takes a job herding cattle cars, working for an arrogant boss who has a beautiful and flirtatious younger wife. During a fight, the boss falls off the train, and Bronco is blamed, but the man's body can't be found.
Army scout Bronco is to find out who's been killing and scalping Apache men, woman, and children. The chief's brother was among the last victims, and Bronco must find the guilty parties before the peace treaty is broken and war breaks out.
To save two Seminole friends, man and wife, from a lynching by former Confederates, Bronco tells them the story of how they tried to help the South in the war by bringing Jefferson Davis' peace offering to their chief in Florida.
A bank is robbed and a teller killed. The four brothers responsible knock out Bronco and make it look like he was involved. He is arrested but escapes when lynch talk gets out of control and heads with the sheriff to find the real robbers.
Bronco rides into Peaceful to see his Army friend Marshal Durrock and his daughter Molly. He finds himself the acting Marshal when the Tilsey gang kidnaps Molly threatening to kill her unless they have free reign to steal a gold shipment.
Bronco has been requested to transport a prisoner to Santa Fe for trial for robbery and murder while a decoy goes on the stage. He loses sealed instructions for an emergency which occurs when a victim's relatives attack them.
Bronco is hunting meat for the railroad in Montana working for Henry Paddock. After a fight over a bear with Theodore Roosevelt, they come to respect each other. Bronco soon realizes Roosevelt is right that his bosses are up to something.
Deputy U.S. Marshal Bronco is asked to go with two marshals to Canada to identify a wanted man - his commanding officer in the war. In Canada they meet with the RCMP who help find the man. However, questions arise about his two partners.
Bronco stops the lynching of a friend who went from gunfighter to minister. The money he raised for a new church was stolen so the parishioners with some encouragement think he stole it. Bronco soon discovers who he thinks really did it.
Bronco finds the owners of the Rocking Chair ranch, Gil Groves and Petrie Munger, have split the ranch allowing a feud to develop. Munger has hired a sadistic gunman, who beats Bronco and Groves' foreman leaving them in the desert to die.
