While walking their horses in the Mexican Desert about 150 miles from the Rio Grande Lucas and Mark are set upon by bandits. Their leader is a man named Miguel who claims to be the Patron of the land and tells Lucas he must pay for the right to walk through it. They rob Lucas of his rifle, horses, boots, kidnap Mark and leave him tied to a tree to die in the desert. Lucas escapes and finds refuge in the house of a kindly girl and her grandfather who nurse Lucas back to health while he vows to get even with Miguel and the bandits.
—tomtrekp