A muscular Western featuring the fisticuffs of Bronson. In 1870, the soldiers at an Army outpost in Utah are supposedly suffering from a diphtheria epidemic. A train heads toward the fort filled with soldiers, medical supplies and Bronson, an undercover agent posing as an arrested criminal. There, he makes a stunning discovery: there is no epidemic, but there is a conspiracy between a group of killers and a tribe of Indians. Fabled stunt man Yakima Canutt helped out, and boxer Archie Moore shows his stuff.