Indians try to reclaim a rancher's adopted daughter.

In the Texas Panhandle sometime after the Civil War, young Rachel Zachary is enjoying a free-spirited gallop on the open range, when she is disturbed by the sight of a strange man. The old man lifts his saber aloft, tells her she is "no Zachary" and shouts that he is "the sword of God." Later, the man appears outside the Zachary cabin, prompting Rachel's mother Matilda, who recognizes the man, to aim her gun at him and chase him off. Soon after, Rachel's brother Ben, who has been on a long trip to Wichita, joins his two younger brothers, Cash and Andy, as they round up horses for the next drive to Kansas. Ben's partner, Zeb Rawlins, brings his family to the Zachary ranch for a visit, during which young Georgia Rawlins announces her interest in Ben, and shy Charlie Rawlins admits he hopes to marry Rachel. Over dinner, the families also discuss their various victories over the "Kiowa devils," Indians from the nearby hills who killed Will Zachary some years earlier. Ben and Cash later search for the mysterious old man, whom Ben knows to be "a Kelsey," but he disappears into a wind storm. One day three Kiowa Indians appear on the Zachary ranch. A young man named Lost Bird offers several horses in exchange for Rachel, who, Abe Kelsey has informed him, is his long-lost sister. Ben angrily replies that Rachel was adopted by the Zacharys after her white parents were massacred in their wagon by Kiowas. The Indians ride away, but after they begin frequenting the area, the local cowboys and their families start to gossip among themselves. When Charlie finally proposes to Rachel, she kisses him in the hope of arousing jealousy in Ben, whom she loves. On his way home, however, Charlie is killed by Kiowas as Kelsey looks on. Rachel attempts to comfort Charlie's mother, but the grief-stricken woman screams that it was Rachel, "a red-hide nigger," who caused his death. Anxious to settle the ugly rumors about Rachel, Ben and his men capture Kelsey and lead him before Charlie's bereaved parents with a noose around his neck. When Zeb demands the truth, Kelsey reveals that years before, he and Will Zachary had killed many Kiowas in revenge for an Indian-led massacre. Zachary took a crying Kiowa baby back to Matilda, who reared the child as her own, then later, when the Indians had kidnapped Kelsey's son Aaron, Zachary refused to swap little Rachel for Aaron. Kelsey had hounded the Zachary family for years after his boy was killed. At this public disclosure of Rachel's secret identity, Matilda beats Kelsey's horse, causing the old man to be hanged. The settlers all shun the Zachary family, and when Matilda later admits that Will had taken the Kiowa infant to replace the baby girl Matilda had just lost, Cash insults Rachel, calls the Zacharys "Injun lovers" and rides away in a drunken stupor. Lost Bird and two warriors approach the Zachary cabin under a sign of peace while dozens of Kiowas wait on the far side of the river. To prevent a battle, Rachel insists on joining them. Finally exhibiting his love for Rachel, Ben orders her to stay in the cabin and has young Andy kill one of the warriors. The shooting leads to a full-scale battle, and the four Zacharys kill many Indians. Rachel, who had wondered if she could kill her "own kind," is assured by Ben that they are similar in blood only. At the Rawlins ranch, Cash hears gunshots and prepares to respond, but Georgia begs him to stay and marry her. The Kiowas send cattle to stampede the Zachary cabin, whereupon Ben sets the house on fire and retreats to the root cellar with Andy, Rachel and his mortally wounded mother. As the fire subsides and the Indians prepare to enter the cellar, Cash arrives, and he and Ben shoot the remaining Kiowas. Lost Bird, however, quietly enters the cellar and looks questioningly at Rachel. In response, she shoots him dead. The Zacharys climb out of the cellar and survey their burned home, their dead mother and a landscape littered with Kiowa bodies. Then, however, their attention is drawn skyward as a flock of birds takes flight.