The Robot vs the Aztec Mummy (1957)

 The Robot vs the Aztec Mummy (1957) aka La Momia Azteca contra el Robot Humano

It being comprised initially of flashbacks to other Aztec Mummy footage it becomes apparent that it is earlier footage than that which we've seen in The Curse of the Aztec Mummy, (yesterday, I had suspicions that I was watching the story in media res.)
We see some of that supposed 'first film', but also of an earlier one (?) which is not included in the MVDvisual set.

In the 'new' footage we hadn’t seen before we get the lecture in which our main scientist Dr. Almada (not Almaden) (Ramón Gay) speaks about past life regression and the exploration of the inside of the Aztec pyramid and the initial discovery of the artifacts and the mummy.

There are some nice bits of menace with the Aztec mummy Popoca* (Ángel di Stefani) taking acting cues from Karloff; menacing the pyramid explorers; kidnapping the girl, and attempting to sacrifice her to the gods, (all this is from a first film? It must be the superior episode!)

The mummy is held back with a crucifix while Flora (Rosa Arenas) is rescued. Knowing the history between Mesoamerican cultures and the Catholic Church it makes quite a bit of sense for the mummy to fear the crucifix, even more than a vampire would.
Since the footage is included here, it might not be necessary to go and search the first film of the series for anyone other than completists and film historians.

After twenty-five minutes of narrated padding (which is still useful if you’ve not seen any other of the chapters,) the story proper begins… or does it? this whole thing is beginning to more and more resemble a serial which was edited together into a series of hour-long features; anyway, we are now finally into new aspects previously unrevealed.
Whatever the real story behind the production might be, it has become obvious that we are watching is not the way the initial concept was meant to be put together.

In standard serial manner, the ending we had seen has now been revised so that Dr. Krupp/The Bat (Luis Aceves Castañeda) is shown to have escaped death and is revealed to be, Svengali-like exerting long-distance mind control over Flora the Regressadora.

Since his Teotihuacan temple** was destroyed, the mummy moved into a Catholic cemetery (forget all that about the mummy fearing crucifixes, that’s clearly not the case and I have no idea what I'm talking about, obviously,) and it is there that hypnotized Flora helps Dr. Krupp find Popoca.

After some Sherlockian sleuthing Krupp’s fiendish actions are discovered. Dr. Almada and Pinacate (Crox Alvarado) go to the cemetery and verify their suspicions.

The narration finally ends forty-five minutes into the feature, and we finally get some real action.
The two amateur detectives locate the nefarious Dr. Krupp’s lair, but they immediately get captured and have Dr. Krupp finally reveal his Frankensteinian designs to them, (it's still not quite clear how the cursed gold is to be used; in this chapter it seems to be merely for their cash value, though there is mention of further treasure.)
Will they escape? We’ve only fifteen minutes left of the feature!

What happens when a slow-moving mummy meets a nearly immobile human robot?
Watch and find out!

Because it condenses the excitement of three films into a single one, other than its unfortunate overlong, narrated flashback format, this might be the best, most efficient way to enjoy the full trilogy (or, at least, to hold your short attention span,) for those of you who only want to see what all the Aztec Mummy fuss is about. Without the padding, however, this would be a mere fifteen minutes long!

Serious film scholars, of course, will still prefer to get the full Aztec Mummy experience which, no matter how one looks at it, is not by way of the K. Gordon Murray versions.

This was a lot of fun. I haven’t seen the MST3K version, but this is the kind of film that’s wild enough already not to need any enhancement.

Recommended by Young America Horror Club.
Check it out.

* The name Popoca is seemingly inspired by a Mexican legend of star-crossed lovers. The volcano Popocatepetl also takes its name from it.

** Film goof: Teotihuacan is not part of the Aztec/Mexica culture.