Even by the standards of the Man in the Silver Mask, this series entry is pretty whacked. Considering this was helmed by Miguel M. Delgado, who also gave us Santo and Blue Demon vs. Dr. Frankenstein and Santo and Blue Demon vs. Dracula and the Wolf Man, this weirdness isn't really that surprising; Delgado seems to have realizes, with his Santo entries, that the mythology and character were established enough for him to do pretty much whatever he wanted. Thus, we get an extended bit where the title villain actually removes Santo's mask. We also get a protracted, unexpectedly brutal duel between Santo and Dr. Lady Frankenstein's slave Truxon (who, despite the name change, is actually Gomar from Doctor of Doom/Night of the Bloody Apes), which I think is the only time I've ever seen Santo beat someone to death. And we also find out that the reason Lady Frankenstein is so bent on capturing Santo is that her eternal-youth serum requires his super-blood. Yes, apparently, Santo has super-blood, which explains his ability to take grievous amounts of punishment and bounce back relatively unharmed as well as his ability to make his wounds disappear in between scene transitions. (Being told this is kind of like the midichlorian revelation in Star Wars: Episode I except that here I think it's stupid on purpose.) Stir in the requisite choreographed beatings, some icky makeup FX and lots of cheese, and you've got a superior Santo entry.