Wolf Caulder is driven by childhood memories too terrible to forget, & by the words of Diego, his spanish rescuer. With his remaining eye Caulder sees frontier justice more keenly than many, & enforces it vengefully with his Colt Revolver. The vengeance trail takes him in pursuit of a ruthless gang of trainrobbers who kill their victims in cold blood. Wolf is on the trail of the ringleader to exact his own brand of justice, and to free a lady driven by a similar revenge. His quest may prove fatal as his keen eye and fast gun are matched by an enemy unafraid to die.