Drifter gunman Joe (Clint Eastwood) arrives in the Mexican village of San Miguel at the border of the United States of America, and befriends the owner of the local bar, Silvanito. Joe discovers that the town is dominated by two gangster lords: John Baxter (Wolfgang Lukschy) and the cruel Ramón Rojo (Gian Maria Volontè). When Joe kills four men of Baxter's gang, he is hired by Ramón's brother Esteban Rojo (Sieghardt Rupp) to join their gang. However, Joe decides to work for both sides, playing one side against the other.