In the 1870s, Will Keough leads his two younger brothers, Bless and Harry, on a cattle drive to the struggling ranch left to them by their late father. When Harry, nicknamed Hade because he is a hothead, wrestles a steer and lands only inches from a rattlesnake, Bless, who is nearby, loses his nerve and Will is forced to take a risky shot to kill it. At home, the brothers admire their new horse, a high-spirited mare that Hade is eager to break. After Bless expresses timid interest, Will lets him ride the horse, but their mother, Hannah Keough, sees her beloved middle son on the horse and strides out to rescue him, embarrassing Bless in front of the ranchhands. Inside, Hannah, who believes that her husband stole away her other boys but left her Bless to pamper and "refine," informs him that she wants them both to move back to her hometown, St. Louis, within the week. Although Bless does not want to leave the ranch, he is afraid of disappointing his manipulative mother. Later, Will tries to intervene on his behalf, but Hannah insists that she will not give up Bless, the only one she loves. Soon after, neighbor Andy Niven visits with his daughter Audry, Will's fiancée, to report that nesters are squatting on the Stringer ranch and stealing cattle. Upon hearing what may be a portent of a range war, Hannah announces that she and Bless are leaving town. That night, a foal is born, which Will promises to Bless. This time, when his mother joins them, Bless summons the courage to tell her that he does not want to leave the ranch. Hannah replies that she will stay and suffer rather than go to St. Louis alone, and Bless wonders why every decision brings pain. Just then, Aud rushes over with the news that a nester has attacked her father, who is trapped under a dead horse, and after Will, Bless and Loving rescue Andy, Bless tells Aud that he worries after her safety. Will confronts the nesters alone, shooting one when he draws a gun, and successfully scares them away. Months later, Hannah is gravely ill, and although Bless decides to take her to St. Louis after she recovers, she dies, leaving him guilt-stricken. Years pass, during which Will builds the ranch into one of the most prominent in the area, all along promising an impatient Aud that they will marry as soon as the work is done. Finally, at the party that before the start of a cattle drive to Abilene, he plans to propose, but she sneaks off to find Bless in the woods. There, she admits that she loves and wants to marry him, and although Bless tries to resist, his love for Aud compels him to take her into his arms. They are exhilarated, but after they return to the party, Bless cannot find the words to inform Will. Stringer then arrives, and publicly denounces Will, who has put in an offer at the bank to buy out the struggling rancher's foreclosed land. When Bless refuses to fight the angry man, Hade punches Stringer, after which Will reasons with him to give up the ranch and join their cattle drive. Although Aud finds Bless's pacifist ways admirable, Bless knows everyone else considers him a coward. The brothers soon set out on the trail to Abilene, where Bless is hard on both Stringer and the mischievous Hade. One night, Will sends Bless and Hade to nearby Arroyo Seco for supplies, and Hade immediately heads to the saloon. There, a local ruffian challenges Hade and Bless, who has followed his brother, to a fight, but after Stringer and his friend join the brothers, the ruffians back down. Bless urges Hade to leave the saloon with him, but when Hade sees one of the ruffians draw a gun, he shoots. After they return fire, Stringer's friend is shot and he blames Bless for not helping them fight back. Days later, after Bless offers six steer to local Indians in return for safe passage across their land, Hade calls his brother a coward. That night, Hade and Stringer pose a fake snake on a sleeping Bless's chest, and a terrified Bless jumps to kill it. Will, who knows that Bless's fears come not only from his mother's coddling but from a long-lived sense of guilt over the death of his father, who was bitten by a rattler after seven-year-old Bless ran away from it, knocks out Hade. Bless, however, then admits to Will that he and Aud are in love, and Will states that he has punched the wrong brother. One day out of Abilene, Will rides ahead alone, leaving Bless in charge, and when the Arroyo Seco ruffians stampede the cattle, Bless orders his men to ride to the mouth of the canyon to head off the herd. Hade, however, wants to stay and fight, and although he kills some of the rustlers, the cattle trample him. Bless rushes back to save him, but is too late, and Stringer spreads the word that Bless abandoned his brother and ran away. They reach Abilene, where Will, too, turns his back on Bless, despite Loving's assurance that Bless did not desert Hade. Aud is the only one who stands by Bless, and visits an angry Will to inform him that he, just as his mother did, tried to make Bless in his own image. Meanwhile, Bless enters the saloon, where the men jeer at him and Stringer challenges him to a fight. Bless punches Stringer, who pulls a gun, but before Bless can respond, Will arrives and shoots Stringer, stating that Bless needs someone else to fight for him. Enraged, Bless punches Will, and the two carry their fight into the street. They are stopped only by the arrival of ranchhand Durkee, who announces that the rustlers are headed to Texas with the herd. Will starts to gather his men but then turns to Bless to continue. A pleased Bless offers gold to any men who join "the Keough brothers," and leads the crowd into the range. Will stays behind, and after they have left, saddles his horse and explains to Aud that she and Bless have his consent to marry, but, just as Bless had to become his own man, Will now has to find his way alone.
