[ Man Narrating ] Gateways to other dimensions.
To the Mayans, this represented the passageway to another world.
Hidden dwellings for strange beings.
They were the first inhabitants of the planet Earth.
Secret vaults of cosmic knowledge.
[ Man ] it's almost as though they're opening a doorway...
to communicate with these divine beings.
[ Narrator] Since the dawn of man...
caves have been a source of great mystery.
[ Bats Screeching ]
But could the darkest recesses of our planet...
really be hiding some mysterious power?
And within their depths...
might we find evidence of extraterrestrial visitors?
[ Man] In some ways...
exploring the underground cavern world of planet Earth...
is the final frontier.
[ Narrator] Millions of people around the world...
believe we have been visited in the past by extraterrestrial beings.
What if it were true?
Did ancient aliens really help to shape our history?
And if so, might there be a connection...
between aliens and the earth's forbidden caves?
Central India.
July, 2014.
While exploring caves in the region of Charama...
which are known to contain prehistoric artwork...
dating as far back as 10,000 years...
an Indian archaeologist, J.R. Bhagat, makes a stunning discovery.
The Indian government and Times of India had a major story...
about rock paintings found recently in Central India...
that seem to show these tall beings...
and they do not seem to have a nose or a mouth...
and nearby is this three-legged disk.
The Times of India actually proposed the idea-
what if what we have depicted here...
are some type of extraterrestrials or at least some type of flying craft?
Because it's the basis for much of the Hindu pantheon of gods.
[ Narrator] Ancient Hindu texts...
like the Vedas and the Puranas...
record stories about extraterrestrials existing on other planets...
and the Mahabharata...
one of ancient India's two major Sanskrit epics...
contains stories about gods coming to Earth in flying machines.
Even the legends specific to this region...
tell of a mysterious race of beings known as the “rohela”...
who descended from the sky and abducted local villagers.
Could the newly unearthed cave an' be a visual record...
that extraterrestrials really visited here?
There was an obsession of ancient human beings...
to depict things that they saw...
and I think they did it with carvings on caves...
because that's what they saw.
[ Narrator] But what is it about caves that made them the ideal canvases...
for ancient peoples to chronicle their experiences?
Caves are hugely significant in ancient mythology and legends...
especially about the gods.
They seem to be kind of a luminal point...
a boundary place where the gods and humans can meet.
[CHILDRESS ] There is a whole hidden underground world of planet Earth...
that we're only just now beginning to discover.
We don't know what's there.
We could be discovering all kinds of amazing things...
and it's possible...
that there are entire cities under the earth-
whole cavern metropolises...
that are talked about in legends.
[ Narrator] But while ancient cave art...
often reveals the type of animals our earliest ancestors encountered...
and their means for hunting them...
there is a surprising number of depictions of strange-looking figures and objects...
that defy any conventional explanation.
In Australia, the Wandjina people, they painted images on their caves...
which eerily looks like the so-called Greys of alien abduction lore today.
You have the strange petroglyphs...
in the Hoggar Mountains of Southern Algeria.
Uh, you've got strange rock art too, in the American Southwest...
and when you look at it, and even have the natives explain it to you...
they say things like, “Oh, yes, he's Martian god,” or...
“These are the star people coming from the sky.”
[ Narrator] How do we explain so many different cultures...
across thousands of years and thousands of miles...
producing such consistent visual representations?
The ones that were discovered in some of the African caves-
it's too similar...
to what has been discovered on every continent...
for it to be complete coincidence.
So, it's this whole idea of the spark of initial inspiration.
What is it that they witnessed?
And could it be that they witnessed extraterrestrials?
One of the more intriguing aspects...
of the cave paintings that seem to show aliens...
is why are they inside caves?
This has sort of given rise to the theory that maybe these aliens...
perhaps have permanent bases on the planet underground.
Maybe ancient man saw them coming out of some of these caves and caverns...
and then realized there was a relationship between the aliens and the caves.
[ Narrator] In ancient times, caves were places of shelter.
But is it possible our ancestors were also using caves...
to record and protect information...
about extraterrestrial beings who played a role in our existence?
Perhaps the answer can be found...
halfway around the world, in the American Southwest.
The Grand Canyon.
This epic, 277 mile-long, one mile-deep fissure...
exposes millions of years of geologic strata.
Imprinted onto this dramatic landscape...
are petroglyphs that depict everyday life...
as experienced by the first inhabitants of the region.
But in one of the most remote corners of the canyon...
is a small cave covered with artwork that mystifies experts.
Some refer to it as the Shaman's Panel...
because it appears to depict scenes of the supernatural.
All around the Grand Canyon are unusual sites and sacred sites.
And then you have the Shaman's Panel there in the Grand Canyon...
which seems to show these long, tall extraterrestrial-type figures.
Like the strange-looking beings found in the cave in Charama, India...
the figures depicted on the Shaman's Panel...
are oddly elongated...
and are also thought to have been created as many as 10,000 years ago.
And just as in Charama...
the native Hopi people here also have detailed accounts...
of extraterrestrials who came down to Earth.
In the Southwest, the Pueblo Indians, such as the Zuni and the Hopi...
believe that there is an entrance into an underground world...
and it is located in the Grand Canyon.
And it's this mythological underworld...
uh, of caves and extraterrestrials, the ant people.
The Hopi have this concept of the ant people.
Uh, the ant people are very thin.
They have elongated heads.
And the ancestral Hopi people...
did make pictures of these ant people which still survive today.
[ Narrator] Is it possible the rock art found here...
and elsewhere around the world...
is evidence that the earth's first inhabitants...
had contact with otherworldly beings?
And if so, might there be some significance to the fact...
that many of these strange petroglyphs are found in and around caves?
Ancient astronaut theorists say yes...
and suggest further evidence can be found...
by examining the ritualistic practices...
that continue to be performed inside caves even to this day.
The Himalayas, Northern India.
- [ Chattering ] - [ Horse whinnying ]
Every summer, hundreds of thousands of Hindu pilgrims...
brave an arduous journey.
They cross many miles of deadly terrain...
to reach the Amarnath Cave-
a place of worship for thousands of years.
12,756 feet above sea level in the Himalayas...
is the most revered holy pilgrimage site...
for all of the people who follow the Hindu faith.
[ Man ] People die because of high-altitude sickness.
Others simply fall off the cliff.
And still, people go there...
because it is considered to be the most holiest, uh, shrine.
[ Narrator] According to local lore...
this massive cave is where the god Shiva...
revealed the secrets of immortality and the creation of the universe...
to his wife, Parvati.
[Shouting In Foreign Language]
To honor Shiva, worshipers pay their respects to a sacred relic inside...
an ice lingam...
which they believe is a physical manifestation of his generative power.
To reveal the secret to transcending the flesh...
the secret to true immortality...
makes that site of extreme importance to the people in the Hindu faith.
[Shouting ]
[ Narrator] To the Hindu faithful...
who risk life and limb to reach the Amarnath Cave...
this story is a real account of an otherworldly being. -.
Who was at this exact location here on Earth.
But why would Lord Shiva choose to divulge his divine secrets in a cave?
Could caves really hold special properties...
that have made them places of worship throughout history?
Interestingly, the Amarnath Cave...
is only one of hundreds of caves around the world...
that have been, at one time, considered sacred.
Archaeologists believe...
a 20-foot long serpentine rock carving in Botswana's Rhino Cave...
was the focus of religious ritual as far back as 70,000 years ago.
And cave monasteries can be found in France...
Russia...
Thailand...
Ethiopia...
and Hungary. ..
Just to name a few.
[ Man ] I don't think that this is a coincidence...
that places of refuge, spiritual refuge, are inside caves.
This is where one can contemplate...
one can hear one's inner voice...
without the distractions of the day.
One thing about caves is they're underground. They're unseen.
Well, religion is about unseen things.
Going into a cave is going into holy ground.
[Chattering ]
[ Narrator] Is the mysterious nature of caves...
enough to explain why they have been revered as sacred places...
by different cultures and religions all over the World?
Ancient' astronaut theorists suggest there may be a more profound reason...
which can be found by examining the stories behind our ancestors' rituals.
Yucatan, Mexico, 2008.
Mexican archaeologists exploring just outside the capital of Merida...
make an historic discovery-
an aquatic underworld full of mysterious offerings to the Mayan gods...
including human sacrifices.
What they found was a system of 14 caves...
and in them were stone temples...
and they were all linked together.
And it was thought that what they had discovered...
was the Mayan underworld known as Xibalba.
[Young ] Some of this work is underwater.
Divers would have had to hold their breath and go down...
and do carving underwater to make this possible.
They were very devout, to be sure.
[ Narrator] Central to the heavily Mayan ritualistic society...
was the belief that in order for them to rejoin the gods in the next life...
the dead must make their way through a dark and perilous journey.
In the mythology of the Maya...
we have these incredible references to Xibalba...
which means “the underworld.”
And we can read about it in the PopolVuh...
which is the book of the Jaguar priests.
[ Narrator] Some historians believe...
that the caves discovered in 2008...
are indeed those caves that represented for the Maya...
the passageway to Xibalba, the underworld.
But ancient astronaut theorists propose...
Xibalba has a more cosmic connection.
One of the most famous code breakers-
her name was Dr. Linda Schele.
She dealt with the Maya language all her life.
She is actually one of the people who have suggested...
that there is another meaning for Xibalba...
and that's “the Milky Way.”
[ Man ] To the Mayans, who were very good astronomers...
this represented the passageway to another world-Xibalba-
the middle of the Milky Way.
So when they refer to the underworld...
they're actually referring to the sky above.
[WILCOCK ] This suggests that the cave could be a portal...
in which extraterrestrials are actually able to come and go freely...
from their plane of existence to our own.
[ Narrator] Is it possible that the Mayan stories of Xibalba...
were not describing a passageway to the afterlife...
but a portal to another part of the universe?
Ancient astronaut theorists suggest...
that caves have become places of ritual...
because they have a direct connection to extraterrestrials...
and claim that further proof can be found...
by examining the mysterious Sky Caves of Nepal.
Shikoku Island, Japan.
The eighth century AD.
A young monk named Saeki Mao...
was deep in the mountains doing his spiritual training...
when he decided to enter a small cave called Mikurodo and meditate.
While inside, he had an encounter...
that he would later credit with bringing him enlightenment...
and he emerged from the cave as Kukai, a high priest-
who would become one of Japan's most important historical figures.
Many Buddhists have reported enlightening experiences in caves.
And one of the most famous stories involves the monk Kukai.
He is the individual who brought esoteric Buddhism, Shingon Buddhism...
to Japan from China.
And according to his autobiography...
he was meditating in a cave at Cape Muroto.
And he had fixed his eyes on the morning star.
The morning star flew towards him...
entered his mouth...
and in front of him he saw an image of the Bodhisattva Akasagarbha.
And Akasagarbha, in Japanese, is known as Kokuzo Bosatsu.
So, we have this spiritual being surrounded by light-
perhaps he even used the light to travel there.
[ Narrator] After this encounter, Kukai suddenly had great wisdom...
including the ability to comprehend 85,000 Buddhist texts.
But what happened inside Mikurodo Cave...
that allowed Kukai to enter this enlightened state?
Kokuzo appeared to Kukai in the cave when he was in his trance...
and basically, informed him that he was a conduit to the universe.
And it channeled through his body...
and he could tell you anything about the stars, the planet.
It was almost as if he were tapped into a database.
Some even perceive that the cave is similar to a womb.
So a human being enters as a normal mortal.
They engage in ascetic or meditative discipline within the cave.
And when they exit the cave, they're no longer a typical mortal...
but they're more akin to a saint...
or even a Buddha.
[ Narrator] But could the enlightenment found inside caves...
be coming from an extraterrestrial source inside the earth?
Some ancient astronaut theorists say yes...
and suggest evidence of this...
might be found in the fabled nirvana known as Shambala...
and the Sky Caves of Mustang in Nepal.
Some say Shambala is a mythical city...
that's located somewhere in the mountains in the Himalayas.
Its inhabitants are supposed to be fully enlightened beings...
who have access to a great amount of technology...
which comes from the enlightenment itself.
[ Mott] Buddhism has always seen caves...
as more or less a conduit to altered states of consciousness...
to other civilizations that may exist inside the earth.
The Sky Caves in Mustang are interesting...
because there are a hundred or so man-made caves...
carved into the faces of cliffs.
And are only accessible by these huge vertical shafts.
And inside these caves, we have huge statues of Buddhas, bodhisattvas.
[ Narrator] And Buddhists are not alone in this belief.
Hindus also revere caves as places where monks can go to find wisdom.
The Sadhu are Indian holy men who, basically...
lead a life of depravation, self-imposed exile in caves...
so that they can enter these altered states of consciousness.
They definitely believe that caves are a conduit...
to communicating with nonhuman entities.
It's almost as though they're opening a doorway into a spiritual consciousness...
in which they are able to communicate with these divine beings...
and hopefully become divine themselves.
[ Narrator] Other important figures throughout history...
also attribute their life-altering epiphanies...
to mysterious encounters that happened in caves.
In the life of the great artist and inventor, Leonardo da Vinci-
he'd had some unusual but important experience at the mouth of a cave.
Right after that, he disappeared for two years.
And fight after that...
he began this spurt of creativity that was awesome.
In art and in science...
he invented the first self-propelled vehicle and imagined flying machines.
[ Man ] Joseph Smith wrote that an angel appeared to him...
with the name of Moroni in the year 1827-
told to Joseph Smith- he should go to a certain little hill.
He should pull the stone plate away...
and inside, he would find a cave.
And in the cave, he would find unknown writings.
As all good Mormons know, he found the golden tablets...
which contained a vast amount of data.
[ Narrator] Why are there so many accounts of humans...
having enlightening experiences inside caves?
Is there something about caves themselves...
that facilitate such extraordinary experiences?
Could it be that these people are coming into contact with an extraterrestrial presence?
Ancient astronaut theorists suggest...
that cosmic knowledge may be stored in the very walls of these caves themselves...
and that the proof can be found in Central America...
1,000 feet underground.
Chihuahua, Mexico.
April, 2000.
Miners excavating 1,000 feet below the mineral-rich town of Naica...
drill through a cave wall and make a stunning discovery-
a glittering cavern full of giant crystals that are half a million years old.
The Cueva de los Cristales,
or the Crystal Cave of Northern Mexico- is a very unique site.
And we're talking crystals as big around as a car...
that stretched from the floor to the ceiling of the cavern.
It's a remarkable thing to see.
The incredible Cave of the Crystals in Mexico...
was just accidentally found...
and the discoverers were completely astounded...
with these giant gypsum crystals.
It's fantastic...
and it reminds a person of the Fortress of Solitude of Superman...
where all this information is encoded into these giant crystals.
[ Hawkes ] Now, the significance of this...
is extremely important to the indigenous people of Northern Mexico...
in fact, all of Mesoamerica...
in that the crystals themselves were considered sacred.
They vibrated.
And they believed there was also some properties involved in crystals...
that would provide them a way to communicate with the gods.
Many ancient myths tell us that there are magical apparatus...
that are made out of rock or stone or crystal.
[ Man ] if we look at the properties of many of the caverns and caves...
we see that there's usually some type of lining of crystal or quartz...
and we know that crystal has a vast ability to store information.
Maybe some of these caves are actually storing information...
and that ancient people who meditate in caverns are tapping into this knowledge.
[ Narrator] Might caves that are rich in quartz or crystal...
really possess some special power that' our ancestors were aware of?
Ancient astronaut theorists point out...
that the scientists today are discovering that crystals do, in fact...
have very unique properties.
[ Man ] Quartz and other crystalline structures...
oscillate at incredibly well-defined frequencies when you hit them mechanically...
and they can be activated electrically...
through an effect known as the “piezoelectric effect.”
So you can put quartz in a watch...
and use it as a very accurate timekeeping device.
So quartz could be used in conducting or communicating certain signals.
[ Narrator] In the Silicon Valley of California...
quartz is used to manufacture the small integrated circuits found in computers...
because of its strong semiconducting properties.
Computer chips are also made with a form of the mineral quartzite...
which is a highly-condensed form of quartz.
Today, computer engineers are working on how to physically manipulate crystals...
so that digital data can be stored inside them forever.
The media has dubbed these hard drives of the future-
“Superman memory crystals.”
So, Superman is one of our superheroes who came from outer space.
He came from the planet Krypton.
It was in the process of being destroyed...
so his parents saved him and sent him in a spaceship to our planet.
One of the interesting things in the Superman story...
is that his father was able to program a crystal that traveled with him...
that he was able to use to construct the Fortress of Solitude from.
And it was basically a crystal structure, essentially a cave...
where he could both get away from things...
and he could use the crystals in there to get information.
So one of the things that's interesting in the Fortress of Solitude...
is the way that the quartz technology, or the crystal technology...
seems to be underlying everything.
And so a future that we're looking at is using light in computing.
You have to figure out ways to trap light and to store it-
basically, to create bits on and off and have the light last long enough...
that the signal stays there and the memory is stored.
[ Narrator] Was the power of crystals...
something the ancients not only knew about...
but utilized by building structures that would harness and transmit it?
[ MARTELL ] A lot of the pyramids had either granite or some type of crystal-lined surface.
For instance, Giza, those great pyramids were topped...
with an obelisk made of shiny granite crystal.
And when we look at an obelisk...
it very much resembles some type of power rod, maybe a Tesla coil.
Ancient times, the obelisk was always a symbol of power.
Maybe this wasn't just emotional power...
but actual physical power that was being harnessed by these objects.
Crystals are transformers. They hold energy.
And, indeed, caves are thought of as “hot spots”...
where you have Earth energy emerging from the planet.
[ Narrator] If scientists today...
are looking into the technological uses for crystal...
is it possible that there are extraterrestrial civilizations...
that have already mastered this technology?
Ancient astronaut theorists say yes...
and that the mineral properties found inside caves...
have enabled some of the world's most astounding miracles.
Bethlehem.
The Church of the Nativity...
built around 330 AD by the first Christian Roman emperor, Constantine...
is one of the oldest continuously operating churches in the world...
having survived invasions, regime changes, fires and earthquakes.
Many claim that the church is protected by a higher power...
because it sits above a cave that some Bible scholars believe...
to be the true birthplace of Jesus Christ.
There are many books about the story of Christ's life, Jesus' life...
which never made their way into the Bible...
and one of them was called the “Protoevangelium of James.”
And in that story, Joseph and Mary are approaching Bethlehem...
and Mary says, “I'm going to give birth.”
And he thinks for a minute. He said, “Ah, I know a cave near here.”
And they're met at the entrance to the cave by a brilliant light.
And when the light dissipates...
there is Mary holding Christ in her arms.
And if you look at Byzantine painting...
the nativity is always represented in a cave.
[ Narrator] According to the Gospel of Luke...
Mary gave birth and places the baby Jesus in a manger...
but no actual location for the nativity is given.
It is known, however...
that caves at the time were commonly used as shelter for livestock.
Going back to the third century...
they started this idea that he was actually born in a cave.
But then they also describe the tomb of resurrection as a cave...
as a simple hollowed-out room that had this circular stone at the entranceway.
[ Gervers ] The Bible does make a point that when Christ was taken from the cross...
and he's buried in a rock-cut tomb.
There does seem to be a mystical environment here-
this idea of a cave being a place...
where someone who is of divinity comes and someone who is of divinity leaves.
So it's almost as if passages are happening in caves.
Constantine's building program of churches in the Holy Land...
began by building churches over caves...
associated with key mysteries of the faith.
He built a church over the site of Jesus' birth.
He built a church over the site of Jesus' crucifixion...
where the Church of the Holy Sepulchre stands today.
And he built a church on the Mount of Olives...
over a cave associated with the site of his ascension into heaven.
[ Narrator] Is there some significance to the fact...
that both Jesus' birthplace and resurrection...
may have occurred inside caves?
Some ancient astronaut theorists say yes...
and claim there may even be physical evidence...
that what happened within these caves...
was something other than miraculous.
The Shroud of Turin is certainly the most important relic of the resurrection-
this extraordinary imprint of the crucified body on this cloth...
that no one has ever been able to accurately explain or reproduce.
[ Mott] When Jesus was in the tomb...
and some believe there was an intense burst of energy...
which created what we now call the Shroud of Turin...
as some form of radiation which was very intense and powerful.
[COPPENS] We know with 21st Century technology...
that the Shroud of Turin is a first-century garment.
And we know, beyond a shadow of a doubt...
that it could not have been painted or in any way created.
So the Shroud of Turin gives us this exceptional piece of evidence...
that something powerful happened in that tomb.
[ Mott] And when people came to see him the next day to view his body...
he was gone.
Two shining beings, nonhuman beings...
met these two witnesses outside the tomb...
and informed them that Christ had arisen and that he had departed.
[ Henry] it's possible that that cave...
was acting as a sort of a gateway or a portal...
because in many of these stories, the caves link Earth and heaven.
[ Narrator] Could the Shroud of Turin...
really be evidence that something of a technological...
as well as a spiritual nature...
took place in the cave where many believe Jesus was resurrected?
Reports of humans encountering the divine in or near caves...
come from all corners of the globe going back thousands of years.
[ Carter ] We look at the prophet Muhammad at Mount Hira.
He's in a mountain in a cave. He's praying and meditating.
He hears the voice of Gabriel.
"Iqra, Iqra." which means to "recite, recite."
And so, he recites the Koran.
According to the Hebrew tradition...
the prophet Elijah, who existed around 9 BCE...
lived in a cave.
According to Greek mythology, Zeus was born in a cave.
[ Thunderclap]
And caves are often understood, in religious traditions...
to be gateways to the underworld.
So, caves are worshipped throughout the Mediterranean...
usually because a god is associated with that cave.
A god is worshipped in a cave or in a grotto.
[ Thunderclap]
[ Narrator] Could the stories of Zeus, Muhammad and even Jesus...
be evidence that the world's subterranean caverns...
might be portals that connect us to other realms...
as ancient astronaut theorists suggest?
Perhaps the answer will be found...
with new cutting-edge technology...
designed to uncover secrets in cave walls...
not visible to the naked eye.
Santa Monica, California, 2014.
Here at xRez Studio...
visualization artists Greg Downing and Eric Hanson...
are pioneering the use of photogrammetry and special-effects software...
to assist archaeologists in the global effort to decipher ancient cave art.
We use a combination of techniques...
from the fields of computational photography and graphics...
in order to help the archaeologists reveal information...
difficult to see just with basic vision when you're there.
[ Narrator] The team recently traveled to the Grand Canyon...
to compile a massive, in-depth photographic compilation...
of the collection of strange petroglyphs known as the Shaman's Panel.
We were drawn to the panel for two primary aspects.
One was the rich layering of the anthropomorphic figures...
and two is the kind of evocative, surreal nature of their composition.
[ Downing ] This cave is maybe, like, five- or six-feet deep.
So, by using a photogrammetric technique...
we're able to get the detail across the entire painting.
[ Hanson ] The nice thing about this technique is...
we can separate the different dyes and minerals that are used.
And in this case, now we can kind of see the layering expressed-
we can see figures that are simply lost by the naked eye.
Yeah, that brings it out.
Yeah, it's a complete difference.
[ Narrator] Could modern techniques one day...
uncover even more details about what ancient people really saw...
and hoped to communicate with rock art?
Some ancient astronaut theorists believe one compelling clue...
that modern researchers might be on the right track...
can be found, oddly enough...
in contemporary America.
March, 1945.
Amazing Stories magazine publishes an article entitled...
“I Remember Lemuria!”
But according to the author...
this is the first piece to appear in the science fiction magazine...
that is not fiction at all...
but an actual account of his own alien abduction.
[ REDFERN ] Richard Shaver was a man who surfaced decades ago...
with a story of underground entities...
that were very hostile to the human race.
Terrible creatures that would kidnap and kill members of the human the race.
[ Man ] They were the first inhabitants of planet Earth.
When the sun became radioactive...
these people could no longer live on the surface.
Some left in their spaceships. Others went underground.
[ Narrator] Could Richard Shaver's account...
of underground extraterrestrials abducting humans be true?
Shaver proposed that the alien race that once populated the earth...
had developed highly specialized equipment...
that allowed them to embed multifaceted imagery into stones.
[ Man ] Richard Shaver believed that he had made...
the greatest discovery in the history of mankind...
about the true nature of intelligent life on Earth.
So this is an original Shaver photograph of a rock book.
And this multidimensional way of making images in the rock books...
was something that Shaver saw as a real sign...
of the superior intelligence of the ancient races.
And Shaver believed that these weren't mere rocks with random patterns...
that these were actually deliberately manufactured artifacts...
by the ancient races who had been here 30,000, a hundred thousand-
who knows how many years ago.
[ Narrator] Might Richard Shaver have actually discovered...
real physical evidence that extraterrestrials have been here on planet Earth...
and might still be here today?
Whether or not Richard Shaver's stories are true...
it does dovetail with legends across this planet...
of a race of beings that either created humankind...
or were, at least, our ancestors...
that had a superior technology.
[ REDFERN ] If we're looking for extraterrestrials...
ironically, the heavens above might not be the best place to look.
We should, perhaps, even be looking deep below our feet.
[ CHILDRESS ] In some ways...
exploring the underground cavern world of planet Earth...
is the final frontier.
[ Narrator] Is it possible...
that some of the world's most mysterious caves...
really are home to extraterrestrial beings?
Could it be that the knowledge of the universe...
has been left for us to discover right here on Earth...
once we have the technology to unlock it?
And might the crystals found within cave walls...
not only tell us where we came from...
but even provide the technology...
to access the most distant corners of the universe?
Perhaps one day we will find proof...
that there is life beyond our planet...
by searching deep within it.