Of course Santo should fight La Llorona. And why shouldn’t Mantequilla Nápoles — born José Ángel Nápoles — who was a real-life boxer who went undefeated for forty years also be in this? Plus, who better than René Cardona Sr. to play the crime boss Severo Segovia?
All of this starts when a professor — the learned elders who populate every Santo movie — asks our hero to help him take a medallion from the corpse of Eugenia Esparza, which is really a map to a treasure in gold coins. Santo wisely says no and the professor explains the story of La Llorona, in which Eugenia learned that Gonzaga, the father of her children, was about to marry another man. She makes a deal with Satan that if she poisons her kids and kills herself that the man will be convicted and executed. And if not, she will come back from the dead to torment him, which is exactly what happens as she fills all of the first born children of his family after he is acquitted and the gold — which was stolen from the queen, so this would doom the man — is never discovered.
The next descendent to die will be the professor’s nephew Carlitos. The older man promises Santo that he will give the money to a children’s charity and together, they will break the curse of the crying woman.
Santo and the boxing champ never really fight La Llorona, as it would not be seen as noble to have them battle a woman mano y mano.