After a group of violent lepers escapes from a sanitarium, - robbing several farms, residents of the town demand the the sheriff - take action. Meanwhile, a local criminal joins forces with the lepers - to commit even more robberies. As the disfigured madmen keep the - entire town indoors with its reign of terror, the sheriff has no - choice but to call on the only man who can help--legendary wrestling - superhero, Santo!

When Santo accompanies a troupe of archaeologists in the search for Aztec artifacts, they find the Mummy of an Aztec who leaves a warning to those who tamper with his resting place. The adventurers ignore the warning, and before long, the Mummy starts bumping them off one-by-one with his bow & arrow.