In Colorado, some years after the Civil War, stranger Larry Venables rides into a small cattle community in search of former Confederate guerrilla fighter Steve Sinclair. Out on the Double S ranch, Steve welcomes home his brash younger brother Tony, who has been away several weeks in Jeweltown, selling cattle and purchasing supplies. To Steve’s surprise, Tony has brought along saloon singer Joan Blake, whom Tony declares he intends to marry. When Tony shows Steve a new pistol he purchased in town, Steve warns him that the unofficial head of the valley, Dennis Deneen, has forbidden the use of firearms in the area. Tony scoffs, explaining that since Steve has forsworn his violent past, it is up to Tony to protect the ranch. While Tony practices shooting, Steve tells Joan that his brother is too young to marry and that ranch life is too harsh for a city woman. When Joan assures Steve that she is used to hard work and is sincerely attracted to Tony’s boyish innocence, Steve confides that he is grooming Tony to run the ranch. Steve then explains that he was once Deneen’s trail boss and that the Double S is part of valley land owned by Deneen. The next day, Steve, Tony and Joan ride into the small town to deposit the money from the cattle sale. When Tony runs into the Double S’s former top hand, Dallas Hanson, he invites him for a drink and despite Joan’s hesitation, insists that she accompany them to the saloon, while Steve continues to the bank. Shortly afterward, Venables arrives at the bar and although he discovers that Tony is Steve’s brother, he insists on talking to Steve alone. Feeling slighted by Venables’ attitude, Tony provokes him, hoping for a gunfight. Just as the men are about to draw on each other, Steve arrives and calls out, thus distracting Venables, allowing Tony to outdraw him. Tony is puzzled when Steve berates him for killing Venables. After Steve departs to inform Deneen about the shooting, Joan asks Tony to take her home, but he insists on buying everyone in the saloon a drink instead. At Deneen’s ranch, Steve explains that Venables was seeking revenge on Steve for murdering of Venables’ younger brother years earlier. Deneen reminds him that since he lost his own son to violence, he has forbidden it throughout his valley and warns Steve that should Tony resort to gunplay again, he will be forced to leave. Riding back to town, Steve discovers Joan alone outside of the saloon while Tony continues celebrating inside. As Steve accompanies Joan back to the Double S, Joan expresses her distress that Tony is acting so immature and reckless. Steve criticizes her naiveté for not understanding that Tony has been shaped by a childhood fraught with the violence of war. When Steve and Joan then see a small wagon train stopped in the valley, Steve investigates and discovers that former Union officer Clay Ellison has returned to land formerly owned by his father, with the intention of farming it. Steve advises Ellison that the land is Deneen's cattle land and not suitable for farming, but Ellison insists that his family and friends intend to settle there. Shortly after Steve and Joan depart, Tony and Dallas drunkenly come upon Ellison and harass him until Steve, hearing the commotion, returns and forces Tony to leave. That evening Ellison calls on Deneen to ask if he can count on the older man to defend his property rights against the angry cattlemen. Deneen admits his aversion for fencing in grazing land, but agrees to give Ellison protection. Meanwhile, when Tony returns to the ranch, Steve chides him for his reckless, brutish behavior and Tony accuses Steve of being jealous of his youth and shooting skills. When Deneen arrives later to inform Steve of his intention to allow Ellison to settle, Tony is outraged, declaring that their ranch is being threatened. Dismayed by Steve’s acquiescence to Deneen’s decision, Tony decides to challenge Deneen and Ellison. The next morning, Tony confronts Ellison, Deneen and Steve outside the saloon, demanding that Ellison and his family leave the valley. When Ellison refuses, Tony shoots him. Deneen then declares that the Sinclairs must give up the Double S and leave the valley and Steve returns to the ranch to inform his men. Puzzled by Steve’s behavior, Tony asserts that he will take over the ranch and fight off Deneen, but the hands refuse to support him. Steve laments to Joan that perhaps he is responsible for Tony’s wildness, but she says he has done his best. That afternoon, angry about the hands’ disloyalty, but determined to remain at the Double S, Tony patrols the ranch borders. Upon spotting Deneen with barbed wire, Tony threatens him and the confrontation ends with the two men shooting each other. Later, Deneen’s foreman and long-time friend, Brick Larson, rides out to tell Steve that Deneen is gravely injured and they are searching for the wounded Tony. Taking his gun, Steve goes in search of Tony and after some hours, finds him hiding. Tony struggles to crawl away, but is too weak, so turns against Steve, determined to fight it out. When Steve draws his gun, however, Tony abruptly shoots himself and, before dying, confesses he wanted to spare Steve from killing again. Returning to Deneen’s, Steve reports Tony’s death and promises to depart, but Deneen asks him to remain. Steve agrees and returns to the Double S to ask Joan if she will stay on with him.