A Cavalry doctor defies orders to treat Native Americans.

In removing a Comanche arrow from an officer's leg, Fort McCullough's drunken Dr. Gibson severs his patient's femoral artery. Capt. Peter Blake watches the young man die and then attacks the doctor, calling him a "murdering butcher." Later, Col. Ethan Walters, commander of the post, complains in a letter to the U.S. Surgeon General that the last three medical officers assigned to the fort have been alcoholic incompetents. Some time later, a train arrives from the East, carrying the colonel's wife, Martha Walters, her pretty and flirtatious niece, Laurie MacKaye, and the fort's new surgeon, Dr. Allen Seward. Distrustful of all physicians, Blake is unrelentingly hostile toward Seward, who is not only very young, but completely inexperienced at handling horses and firearms. During the two-day ride back to the fort, Seward asks Sgt. Creever, an Irish immigrant with a fondness for "rare old Irish whiskey," if the local Kiowa Indians are "tame." Creever explains that although the Kiowa now live on a reservation, they successfully resisted the Cavalry's attempts to get them there for many years. That evening, Creever is knocked unconscious by some Indians, who quietly enter the camp to steal rifles and cartridges. Seward catches a glimpse of them and then attends to Creever. Back at the fort, some of the men show their appreciation for the skill and determination with which Seward treats his patient and cleans up the filthy fort hospital. Blake is unconvinced, however, and at the Kiowa reservation, treats the Indians roughly. He demands that Seward identify the gun thieves, but the doctor does not comply because he is too preoccupied with a young malaria patient, the son of Manyi-ten, a white woman married to Chief Satanta's son Red Leaf. Seward addresses Isatai, the medicine man, with respect, thereby earning the trust of the Kiowa healer. Later, Seward learns that the illness has spread. Disregarding orders, Seward again visits the reservation, where Isatai, himself sick, takes the doctor's quinine in order to convince the others of its efficacy. Manyi-ten, who reveals that she was reared by the Kiowa after her white parents drowned, tells Seward that the reservation's water supply is bad, but that up in the hills, the water is clean. Seward advises the tribe to go there, but Blake arrives and orders him back to the fort at gunpoint. At that moment, Red Leaf, who refused to take Seward's medicine, dies. As they are returning to the fort, Blake and Seward are attacked by the gun thieves, who turn out to be Comanches. A Cavalry unit arrives in time to save the two men, but the Comanches get away. The colonel again orders Seward to avoid the reservation, but the doctor refuses to comply, protesting that the Kiowa are ill only because they must live on a poorly situated reservation. Seward is arrested but ordered to join Blake in locating the Comanches. While searching the area, they discover that the Kiowa have left the reservation. Blake's men spot the Comanches, but the Kiowa, heading toward the hills, see that Blake is about to ambush them. In the fierce battle that follows, the Kiowa lend the Comanches their assistance, and many soldiers are killed. The injured troopers, who blame Seward for the Kiowa revolt, refuse his treatments, calling him by the nickname Blake has pinned on him, "Woodhawk," a bird that turns against its own kind. Manyi-ten warns Seward that the Kiowa, now formally allied with the Comanches, are planning a major attack, and shortly afterward, a patrol races into the fort just ahead of a crowd of charging warriors. The soldiers try to defend the fort, but one of the soldiers is ill, and soon half of the men are stricken with malaria. They blame Seward for this, too, but Laurie defends and encourages him. Seward steals away to the Indian camp to persuade the Kiowa to make peace, but Blake, assuming the doctor is a traitor, hides behind a tree and fires at him. By mistake, the captain hits Spotted Wolf, Satanta's only surviving son and Manyi-ten's new husband. Seward returns to the fort with an ultimatum from the Indians: Either let Seward use the hospital to operate on Spotted Wolf or face immediate attack by the allied Kiowa and Comanche tribes. Col. Walters admits the doctor, his patient, and the two Indian chiefs, and then waits worriedly while Seward operates. Finally, the chiefs emerge from the hospital, and Satanta praises Seward not only for having saved his son, but for treating the Indians as brothers. Col. Waters promises to help move the Kiowa to the high country, and the men shake hands. Seward takes Laurie's arm, and the couple returns to the hospital.