In the old west town of Absolution, a man who has lost his memory wanders into town wearing a strange high-tech cuff on his wrist. Someone recognizes him as outlaw Jake Lonergan. He escapes arrest and a pursuing posse, but a woman named Ella knocks him out, and Jake is taken into custody. Rancher Dolarhyde demands that Jake be released into his custody, claiming that the Jake stole his gold. During a tense stand off, alien spacecraft begin attacking the crowd, and Jake's cuff becomes a weapon that shoots a ship down--but not before the aliens have kidnapped and made off with several of the townspeople. The aliens have been abducting people to experiment on them and mining the world for gold that can fuel their spacecraft.
An alien escapes from the wreckage of the ship, and Dollarhyde, Ella and a group of others go out to track it. Jake takes the opportunity to travel to an empty cabin, where he has a flashback of being abducted himself. He joins the posse, which suffers another alien attack before it is then attacked by Jake's former outlaw gang who want the loot he stole from them. The tracking posse escapes, only to face another alien attack. Ella is captured and fatally wounded, though Jake gets her away from the aliens.
The unlucky group is then captured by Apache Indians who blame them for the alien attacks. Ella's body is put into a fire where she is resurrected and explains that she is really an alien come to earth to help protect it from these invaders who also destroyed her own home planet. With Ella's help, Jake remembers escaping from the alien mother ship and stealing the gauntlet weapon. They find the ship, and Jake and Ella free the captives before Ella sacrifices herself to destroy the ship. Back in town, Jake leaves to start a new life.