A young Cullen Baker rides his mule throughout the old west with his father, when bandits attack them, killing his father. Cullen becomes a loner, again riding a mule through the west and getting into trouble wherever he goes. When a soldier shows him the Colt Dragon revolver, a newly invented six shooter, he becomes obsessed with obtaining this gun as a means to empower himself. After murdering two soldiers and taking their revolvers, Cullen proceeds to rob banks and shoot down anyone who dares confront him.