With its ability to deliver 200 rounds per minute, the Gatling gun was the most formidable killing machine to emerge in the Old West. Certain that the gun will make his tribe invincible, Apache chief Two-Knives is determined to seize the weapon being transported by a cavalry detachment led by Lieutenant Malcolm. The jammed gun will not fire, and the horse soldiers find themselves surrounded by over a hundred bloodthirsty warriors. Malcolm stubbornly resolves to hold out to the last man and prevent the renegades from gaining possession of the deadly machine gun.