Tom Mix is working with the Texas Rangers to smash a powerful gang of smugglers. Right now, this gang - led by a mysterious person known as 'The Mask' - is holding the Old Wrangler captive in an abandoned ranch house ten miles outside of the town of Havanas. As Tom and Pecos search for the Old Wrangler, Tom notices a light in the old ranch house, and he and Pecos wheel their horses and ride in its direction! What they don't realize, is that they are being watched...