 Significant changes were made from Horgan's novel in reversing the character traits of the female leads, making Kitty Mainwarring the object of Hazard's affections and Laura the negative personality; and altering the narrative's climax (and history), by reversing the fate of the Apaches from their historic removal to Florida and restoring the male protagonists to full duty, thereby negating Hazard's point-of-honor refusal of the congressional Medal of Honor and resignation from the Army, which was the basis for the entire storyline.Shooting took place in September 1963.Location filming occurred in Flagstaff, Arizona and Gallup, New Mexico.