Laura Montaño, a corrupt landowner who exerts control over a Mexican zone, wants to put an end to her daughter Sara's romance with Julián Moncada, a young farmer. She sends for the legendary gunfighter Maclovio Castro, better known as "One-Hand Maclovio", to kill Julián. However, upon his arrival the mercenary is haunted by guilty memories of his past in the region, he is followed by a man seeking revenge, and the tense power struggle in town obstructs his mission.