Vince Hackett's gang steals a prized victory canon from Mexico and blames the deed on ex-member Jess Wade, who wants to go straight.

Bronson and Marvin star as murderous half-brothers who are running from the law as well as each other. A climatic confrontation proves to each of them just how mean the other can be. "The Meanest Men in the West" is actually an amalgam of two episodes of the hit 1960's TV series, "The Virginian." In one installment, a wealthy man's daughter is kidnapped by a nasty gunslinger. But the crime is only just a means for the ruffian to draw the tough title character into a blood- thirsty revenge scheme. In the second, a drifter burglarizes the Shiloh ranch. Then an unhinged girl relies on the man to aid in her flight from home.