Sergeant Clay Tice a free-wheeling cavalry veteran, clashes with his Sergeant-Major Chambers, a by-the-book disciplinarian. When the Sergeant-Major catches Tyce courting Dulcey at the Wayfarers Inn instead of searching for rustlers with his cavalry patrol, the junior non-com is given a choice of resigning or facing court-martial. Tyce resigns, then rounds up several malcontents from his old troop and stages a kangaroo-court in the Wayfarers Inn with Chambers as the defendant.
Marshal Crown is shot while pursuing a murderous gang of outlaws who prey on isolated Indian villages. He is found, hidden and nursed back to health by Heller, a young woman who was raised by Indians but now works for the outlaw gang. Crown and Heller escape to Cimarron, but are pursued by the outlaws who want to punish Heller for her treachery.
Marshal Crown and his posse thwart a payroll robbery and capture or kill all the entire outlaw gang. The leader is sentenced to ten years in territorial prison, but Crown can't gather enough evidence to charge the youngest member. When the youth decides to stay in Cimarron, the marshal arranges for him to work with an reclusive horse trainer and the youngster takes to both the job and his new boss. His new loyalty is put to the test when the gang leader escapes from jail and returns to Cimarron seeking revenge.
When a band of wolf hunters, whose very success has put them out of business, are becoming a problem for the settlers of the Cimarron Strip. Broke and hungry, they resort to killing cattle for sustenance. Marshal Crown offers them a section of land to homestead, but their leader, Sam Gallatin, believes that the life of an outlaw is preferable to that of a dirt farmer.
Marshal Crown tries to prevent the Houston clan from entering the Mocane Valley before it's open for settlement. The Houston's believe they'll have little competition for prime land because of the legend of a malevolent beast thought to lurk in the valley. When the wagon train is destroyed and most of its travelers killed, Marshal Crown and his men search for the culprits not knowing if their quarry is man or beast.
With Marshal Crown out of town, acting Deputy Marshal MacGregor pursues escaped hired gunman Luther Happ. After tracking down the escaped fugitive and killing him in a shootout, the wounded MacGregor passes out and awakens in a Texas jail, where he is accused by Sheriff Jack Hawkes of murdering Deputy Luther Happ.
When Wilcat Gallagher's Wild West Show hits Cimarron, trouble starts when the shows main attraction features the reenactment of a cavalry slaughter of Indians called, The Battle Of Bloody Stones. When Indians in the Cimarron territory become angry with the way that the battle is portrayed, conflict erupts between the Indians and Wildcat Gallagher's band.
When wanted killers/brothers Felix and Gene Gauge turn themselves in to Marshal Crown and proclaim self-defense in a killing, they become the prime targets of other bounty hunters. With a $15,000 bounty on their heads, a local wealthy rancher hires a couple of ruthless henchmen to gun down the two brothers.
When a potential range war heats up between cattlemen and incoming settlers in the Outlet, Washington sends U.S. Marshal Jim Crown to the Cimarron Territory to quell the dispute. Assigned to Cimarron City, Crown finds that there is no law in the town, and that he will receive no help from the Army. Crown is forced to jail his old buddy ""Bear"", accompanied by sidekick Mobeetie, and his gang of renegade cowboys, when they go on a free-for-all drunk and terrorize Cimarron. Upon their release from jail, the cowboys discover that their boss, cattleman Hardy Miller, has lost his government land lease, due to the government favoring the movement of the incoming farmers and settlers. When Miller is forced to fire Bear and his group, they promise revenge against the settlers and vow to turn the Cimarron River bloody red.