 Cattleman s Association detective Steve Donovan (Reb Russell) arrives in an Arizona border town searching for rustlers. Chief among these is Black Bart (Slim Whitaker) who, among his many crimes, also mistreats his stepkids Lucy (Lois January) and crippled little Davey (Tommy Bupp.)A dog also departs rather quickly when Black Bart is around. Steve beats up Bart in a fight at a town barn dance over Bart s treatment of Lucy. Sonny Carns(Edmund Cobb),a semi-good bad man who has hired out to run cattle over the border for Bart, takes part by keeping henchman Pedro (Dick Botiller) from knifing Steve. Carns also saves Steve s life once more before Bart meets his just end from an unexpected source.