After a winter in New York, Theodore Roosevelt returns to the Badlands to find that his old adversary, the Marquis de Morés, is grazing his cattle on Elkhorn land; Roosevelt and his men are soon thrust into a violent range war to defend their claim.
Theodore Roosevelt's Elkhorn Ranch is threatened by the arrival of a fearsome stranger from Chicago, searching for an associate who went missing a year ago, a mystery that could implicate Elkhorn and lead to the downfall of the Marquis de Morés.
While Theodore Roosevelt and his men help catch a horse thief, the town of Medora is thrown into turmoil when its enigmatic founder, the Marquis de Morés, is unexpectedly arrested and taken to Bismarck to stand trial for the murder of a rancher.
Theodore Roosevelt travels to Bismarck to attend the murder trial of his old adversary, the Marquis de Morés; back in the Badlands, the Marquis' wife, Medora, is visited by her father, who tries to convince her to leave her murderous husband.
When Theodore Roosevelt assists a Sioux brave in finding his stolen horses, they help identify a notorious Badlands horse thief; though found innocent of murder, the Marquis de Morés must still repair his damaged reputation with his father-in-law.
A Chicago cattle baron sends two enforcers to make deals with Medora's ranchers, leading to a deadly confrontation with the town's founder, the Marquis de Morés; sensing trouble, one of Theodore Roosevelt's men heads off to Montana to find some help.
When a ruthless Chicago cattle baron invades Medora with a legion of gunslingers, Theodore Roosevelt must join forces with his old adversary, the Marquis de Morés; together, they hatch a desperate plan to save their town from certain destruction.