NARRATOR: In Ireland, tales of the Sí,
or fairy folk, have been passed down orally
for more than 3,000 years.
And in the 11th century, many of these stories
were documented in a text called "The Book of Invasions."
According to this medieval account of Irish history
and lore, thousands of years ago,
a godlike race of beings called the Tuatha Dé Danann landed
on a mountaintop in Ireland.
Often referred to as the "Shining Ones," they
are the ancestors of the Sí.
MARTY MULLIGAN: All of our stories relate
back to the Tuatha Dé Danann.
For 3,000 years at least, if not more before that,
all of the stories from mythology are all related
to the Tuatha Dé Danann.
They were the Shining Ones.
JENNY BUTLER: There is a description in the mythological
material in the early Irish literature of the Tuatha Dé
Danann arriving in cloud ships, arriving in dark clouds
and landing on a mountain.
KATHLEEN MCGOWAN: There was a long poem about the arrival
of the Tuatha Dé Danann.
One of the lines says, "The truth was not
known beneath the sky of stars whether they
were of heaven or of Earth."
DIARMUID JOHNSON: The Tuatha Dé Danann are not human.
They're demigods, and not immortal, not infallible, not
like the gods of a monotheistic tradition of any
of the Abrahamic religions.
NARRATOR: The Tuatha Dé Danann were said
to be luminous beings of large stature
who wielded magical powers.
The Tuatha Dé Danann had an arsenal of very technological
sounding weaponry.
Lugh of the Long Arm, for example,
possessed a spear that when he thew it,
he could give a voice command, and it would automatically
hit whatever target.
Then he'd give another voice command,
and the spear would mysteriously return to him.
We have circles of light that they used
to travel around Ireland upon.
We have another chieftain named Nuada
who lost an arm in a battle against the giants,
and they were able to replace his arm.
The Tuatha Dé Danann were said to have a magical cauldron.
They had a cloak of invisibility.
They had spears that shot flames out.
The ancient astronaut theory tries to look at ancient
stories in which magic happens from a modern perspective
and determine if that so-called magic really
was some type of technology.
Then one has to wonder, where did that technology come from?
Well, there's only one answer to this,
and that is extraterrestrials.
NARRATOR: For ancient astronaut theorists,
another intriguing aspect of these stories
is how similar they are to accounts of sky gods
found in other ancient cultures.
The stories of, let's call them
aliens, descending from clouds on tops of mountains
are straight across the cultural history of human beings.
Let's start with one of the earliest
ones, the descent on Mount Hermon in the Golan Heights.
That's where Nephilim came down.
Another in the descent of the Anunnaki,
they came from clouds.
DAVID CHILDRESS: We have other stories in Tibet
and other places where these gods are coming down,
and they land on top of a mountain.
The gods of Olympus in Greece as another example.
ANDREW COLLINS: The stories of the Tuatha Dé Danann in these
whirlwinds or clouds is something
that we find in connection with deities
in other parts of the world.
For instance, across the Middle East,
there is the concept of Jinn.
These are supernatural beings very often associated
with fire and light that can appear in whirlwinds
and manifest into physical form.
GIORGIO A. TSOUKALOS: The fact that we have countless stories
that are not just similar but identical
leads me to think that perhaps all
these ancient cultures were visited
by the same extraterrestrials.