Of the many and varied, multifaceted theories that have been advanced to try and explain what lies at the heart of the UFO puzzle, one of the most controversial suggests that rather than representing bug-eyed intruders from far-away star-systems, the assumed aliens are really nothing of the sort. So, what, then, might they be, if not extraterrestrials?

Well, according to some researchers of the UFO phenomenon, our elusive visitors may be the last, possibly even the waning, vestiges of a very ancient, but very terrestrial, race of advanced entities that originated right here on Earth in our distant past. They have chosen – or have been forced – to live outside of human society, and within huge, cavernous underworlds far below the surface of our planet. Yes, it does sound just like wild fantasy. But, incredibly, maybe it is not.

Right up until the point of his tragic passing in October 2009, at the age of thirty-four, author Mac Tonnies was hot on the trail of these ancient, underground humanoids, which he chose to call the Cryptoterrestrials. Tonnies told me, only a couple of months before his death:

“After devouring countless books on the UFO controversy and the paranormal, I began to acknowledge that the extraterrestrial hypothesis suffered [from] some tantalizing flaws. In short, the ‘aliens’ seemed more like surreal caricatures of ourselves than beings possessing the god-like technology one might plausibly expect from interstellar visitors. I came to the realization that the extraterrestrial hypothesis isn’t strange enough to encompass the entirety of occupant cases.”

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