Clay Hardin, a Deputy U.S. Marshal, is about to turn in his badge and take the job as the territory's Indian commissioner until the notorious Ben Thompson slays the marshal when he tried to make an arrest. Clay turns his back on a white-collar job and his girl to pursue the gang. Picking up a bounty hunter and a beautiful half-breed woman along the way, the little band follows the trail into Apache land where the lawman discovers that the outlaws plan to sell repeating rifles to the Indians.

A mad doctor uses patients at his isolated psychiatric institute as subjects in his attempts to create longevity by surgically installing an artificial gland in their skulls.

New Mexico Territory, August 1879. The few surviving members of a cavalry column, which has been relentlessly decimated by the Apaches, attempt to reach Fort Crain. On their way through a hostile land, the obsessive and ruthless Sergeant Vinson takes to the limit the battered will of the troopers under his command.