Here is Dr Frank C. Baxter to explain to us about the history of worlds beneath the earth, something which has set mankind wondering for centuries: could there be civilisations below our feet, in caverns unseen by humanity for countless years? Dr Baxter doesn't entirely believe this, but he knows a lot about the subject, running through various theories until we get to see a fictional representation of the notion when the story begins for real. It is set in Asia, and has a team of archaeologists led by Dr. Roger Bentley (John Agar) searching a remote mountain range for evidence of the Sumerian people - but they find more than they bargained for...
The inclusion of Dr Baxter there appears to be to offer a sheen of scientific respectability to what was inescapably a pulp sci-fi tale, as he would be recognisable at the time for his eductional short films that would have been shown in schools. Imagine going along to your cinema and seeing Sir David Attenborough introducing the latest mid-level monster movie, it wouldn't have happened decades later, would it? Anyway, the other reason that the good doctor appeared would be to stretch out the running time, as without his near-five minute chat this would be a even briefer experience than it already was.
For the first ten minutes, when the team are making their way through a load of stock footage to get to the plateau where a stone tablet and an oil lamp they have found have told them the Sumerians used to live, The Mole People makes this seem as if the cast are more likely to bump into a Yeti, as from this junction it could easily have branched off into an Abominable Snowman flick. It doesn't, though, and before long they have reached their destination in the snow, a temple that by all rights, according to these self-appointed experts at any rate, should have been built next to a civilisation - so where could it possibly be?
They quickly find out when one of their number takes a tumble through a hole in the ground, and they others are forced to go after him. A spot of potholing later, and they are at the bottom of a shaft that promptly collapses in one of the earthquakes that happen with unfortunate regularity round those parts, and they are stranded. But wait, there's a draught from somewhere, so they follow that down a tunnel and lo and behold, they find that civilisation they were looking for. This is where you would expect the Mole People to enter into the plot, and they do to an extent, but they're not the bad guys.
The Sumerians use Mole Persons as their slaves, you see, so it's the albino overlords, who look far more human than the oddly reptilian creatures of the title, who cause our heroes, or what remains of them, all that trouble. At first they think the explorers are gods because they come from up above where no Sumerian can survive thanks to strong sunlight seriously burning them (cue human sacrifice sequences), but when they learn these chaps from the surface are as human as they are, the scheming high priest (Alan Napier, getting quite a lot to do for a change as the main villain) wants to get rid of them. There is also some love interest for Roger, as Cynthia Patrick in her only credited role plays a non-albino slave, but this merely sets up the story for one of the most unnecessary unhappy endings of the era. This is too short to be a drag, but those hoping for some Dero-styled insight that Dr Baxter promises will be let down as this is strictly your basic lost world business.