En route to a bordertown fiesta, Buck invites trouble when he befriends a Mexican boy. Buck encounters Homero Jose, an itinerant promoter whose income comes from fights he stages between friendless Mexican youths for anyone willing to wager on the outcome. Repelled by the sight of 11-year-old Beto being beaten, Buck takes him away in hopes of finding him a new home; but a vengeful Jose takes up their trail, vowing to get the boy back.