In the hills of the Wyoming Territory, Adam Reed, an Indian scout, arrives for a meeting with an old friend, the Cheyenne brave Fire Knife. Fire Knife asks Adam to deliver the yellow tomahawk of war to Cavalry Major Ives, who is known to the Cheyenne as "the butcher" because he was responsible for a massacre in which many Cheyenne women and children were killed. After promising Adam that the women and children living in Ives's encampment will be given time to leave before violence erupts, Fire Knife presents Adam with his father's bow as a symbol of their friendship. Despite Adam's warning, Ives, who hates the Cheyenne with a vengeance, refuses to evacuate the camp, where he is building a fort in violation of a treaty with the Cheyenne. Adam makes plans to travel to Fort Ellis in order to report Ives's illegal construction to their superior, General Faulkner, and in the meantime, meets a number of the encampment's civilian residents, including the bookish Keats, the fort's architect, and Tonio Perez, an affable Mexican adventurer being pursued by Honey Bear, an amorous young Indian woman. Adam also renews his acquaintance with Kate Bohlen, the fiancée of Lt. Bascom, who he had met earlier at a swimming hole. Later that afternoon, a prospector, Walt Sawyer, rides into camp with his seriously injured partner, Willy. Sawyer claims that the two were attacked by Cheyenne warriors, but Adam is suspicious of his story. In answer to Adam's queries, Sawyer claims that they found no gold, but when left alone briefly with Willy, Sawyer finishes him off in order to keep the gold they discovered for himself. Ives uses Sawyer's story of an unprovoked Indian attack to his advantage, declaring that the Cheyenne have already broken their promise. Adam begs Fire Knife for more time in order to reach Faulkner for help in getting Ives to leave the area, but Fire Knife is unmoved by Adam's pleas. Without informing them of the true danger of their situation, Ives gives the soldiers' wives the option of leaving the encampment with Tonio, but all of the women choose to stay with their husbands, except for Kate, who has just broken off her engagement to Bascom and wishes to return to Boston. Ives and Keats, accompanied by two of Ives's men, Corp. Maddock and Pvt. Bliss, ride out to the hills to retrieve a hidden cache of weapons. When Ives opens the metal box, however, he finds nothing but a tomahawk. Before Ives can return, smoke signals appear on the horizon, and the Cheyenne begin their attack, descending on the ill-prepared camp in droves. During the exceptionally violent attack, women and children are assaulted with tomahawks and chased into tents which are then set afire. Although Adam is wounded and knocked unconscious, Fire Knife makes sure his life is spared. Kate, having returned to the camp because she was unable to make it through enemy territory, grieves over the body of Bascom, crying out for vengeance, until Adam reminds her that the Cheyenne were only avenging the deaths of their own families. Tonio and Honey Bear also return, having seen the ominous smoke signals, but they are too late to help. Maddock blames Ives for the murder of his family and wants to shoot him, but Adam intervenes, suggesting that the small band of survivors attempt to make their way to Fort Ellis, where Faulkner will decide the question of Ives's guilt. On the first night of their journey, Kate and Adam reveal their feelings for each other, while Tonio remains impervious to Honey Bear's longings. The following day, the Cheyenne attack, and Keats, Maddock and Bliss are killed. Taking the friendship bow with him, Adam seeks out the warriors and attempts to return the bow to Fire Knife, who refuses it. The Cheyenne braves tell Adam that they want only that Ives be turned over to them, but Adam refuses their request, declaring that Ives must face the judgment of his own people. During the battle that follows, Sawyer, who Adam now knows killed his partner and then blamed it on the Cheyenne, is wounded and dies a slow death, clutching his gold until the end. Honey Bear manages to save Tonio's life by killing a Cheyenne who is about to attack him, and fighting valiantly, the greatly depleted group succeeds in killing all the warriors, save for Fire Knife. In abject fear, Ives calls out to Fire Knife, begging for mercy and revealing the secret explaining his pathological hatred of the Indians: he has Cheyenne blood and therefore planned the massacre as a misguided means of erasing his own past. As no ammunition remains, Adam has no choice but to fight Fire Knife one on one with his bow. After shooting Fire Knife through the heart, Adam sadly leaves the token of their friendship--the prized bow--by Fire Knife's body. Once the group safely reaches Fort Ellis, Tonio and Honey Bear, now in love, ride off in search of new adventures, while Kate remains at the fort to begin her new life with Adam. Ives warns Adam not to reveal the truth of his ancestry, but Adam replies that his only concern is that Faulkner listen to both of their stories carefully, for only the general can decide which approach will best solve the "Indian problem": total eradication of a people or fairness and the honoring of peace treaties.