The man they call Madigan--a rough retired Cavalry officer--finds himself drawn into an intriguing but dangerous game of Cat and Mouse with a formidable gang of outlaws searching for the hidden Aztec gold of Montezuma in the old Southwest. Soon the race is on to find the treasure and save the inhabitants of a Lost City, while Madigan is forced to use his deadly aim with his Sharps buffalo rifle to stay alive and save the woman he loves.