U.S. Army soldiers round up a group of Indians, mostly women and children. Surprisingly, they find among them a white woman and her half-Indian son. Sam Varner (Gregory Peck) is a scout retiring from the Army to his ranch in New Mexico. He agrees to escort Sarah Carver (Eva Marie Saint) and her son after she begs him. She wants to leave immediately rather than wait five days for a military escort. He does this even knowing the child's father is a feared and murderous Apache and that sooner or later a showdown is almost inevitable.