In 1877, young Lot McGuire rides toward the Southwestern town of Suwora, intending to kill Marshal Dan Blaine and thereby prove himself the fastest draw in the territory. By chance, he meets and becomes friendly with his intended victim at a fishing spot outside of town but makes his intentions clear to the marshal. Blaine, a former gunfighter pacified by ten years in prison, sees in McGuire the kind of youngster he himself once was and tries unsuccessfully to make him forget his so-called "mission." After McGuire proves his ability by outdrawing card cheat Squint Calloway, Blaine's dancehall hostess girl friend, Lisa Denton, hires gunman Ernest Scarnes to kill him. McGuire mortally wounds his would-be assassin, however, and confronts Lisa with knowledge of her treachery, although he promises not to divulge it after learning that she was only trying to protect Blaine. As the showdown nears, the desperate Lisa takes a revolver and stalks McGuire herself, but before she can shoot, Blaine stops her; aware now that a duel is inevitable, the marshal outdraws his challenger, tosses away his gun, and sadly leaves town alone.