Young Guns (1988)

In 1878 New Mexico, young men working for rancher John Tunstall seek justice after he's murdered by a rival cattle baron. Deputized to arrest the killers, they turn to vigilantism, with William Bonney—soon infamous as "Billy the Kid"—leading the charge. Their quest for vengeance makes them legends but also outlaws, as they battle Murphy's men and the rules in a fight for survival.