Original subtitles

NARRATOR: Shadowy figures appear in the night,

terrifying all who encounter them.

I don't even know how to describe

-that level of fear... -(gasps)

...because it was this big, hulking black mass.

NARRATOR: They paralyze their prey.

It was like being chained to the bottom of the ocean.

You can't move, you can't breathe.

NARRATOR: And according to some,

they are not only frightening but deadly.

DAVID CHILDRESS: They explained it as

these shadow entities were killing them.

(sustained beep)

NARRATOR: Could dark entities

known as the shadow people

be more than just a product of the imagination?

Are there beings coming to Earth from other worlds

or other dimensions, with malicious intentions

for the human race?

JONATHAN YOUNG: It seems menacing,

it seems from another place.

It's a mystery, but it's a mystery

that a lot of people are encountering.

NARRATOR: There is a doorway in the universe.

Beyond it is the promise of truth.

It demands we question everything

we have ever been taught.

The evidence is all around us.

The future is right before our eyes.

We are not alone.

We have never been alone.

Vientiane, Laos.

December 2, 1975.

In the wake of the Vietnam War,

the Hmong people, a group of indigenous Laotians,

are forced to flee their country

as the Communist Party seizes political control.

Thousands of displaced Hmong people

immigrate to the United States.

But as they become settled in their new communities,

they face an unexpected and much more mysterious threat.

There was a very strange rash of deaths of Hmong men

who suddenly died in their sleep.

And medical technicians could find no reason

for these strange deaths.

If you look at the statistics,

suddenly, when the Hmong people arrived in the United States,

their death rates skied. Why?

Nobody knows why, because they didn't have any symptoms.

They just died.

NARRATOR: After numerous inconclusive autopsies,

mystified doctors were unable to find a cause of death

but gave the phenomenon a name:

"sudden unexpected nocturnal death syndrome."

All but one of the 117 men who died were in good health,

with a median age of 33.

So, while some doctors now speculate that the deaths

might be explained by an obscure genetic cardiac arrhythmia,

the Hmong believe there is another explanation.

Modern medical science could not explain these deaths.

But among the Hmong, they knew it was because

they couldn't practice their original religion.

In Laos, there is a belief that there are night spirits

that are dangerous, but if you have done your rituals,

your prayers, your ceremonies,

and have your ceremonial objects near your bed, you're fine.

It's all under control, when you're in Laos.

But when you're brought to another country

and you're working odd shifts and things,

maybe your rituals get a little off.

So you're in trouble and the night spirits get you

and you die, which is just so strange.

I mean, these are night spirits. They're-- that's superstition,

but they died.

The deaths are real.

NARRATOR: These shadowy night spirits

are known by the Hmong people as "cho chua"

and are often described as "pressure demons."

That is, demons that exert pressure

by sitting on their victims' chests

until they can no longer breathe.

The Hmong people talked about some of the symptoms

they experienced, not just nightmares but visions,

and a terrible pressure on their bodies,

because their ancestral spirits were no longer protecting them.

The Hmong themselves explained it

as these shadow entities were killing and punishing them

for not having done their rituals correctly.

HENRY: The reason why we know that they believed

they were dying from this is because medical experts,

researchers talked with the family members

and that's what they said.

NARRATOR: The Hmong people's description

of their interaction

with the pressure demons known as cho chua

bears a striking resemblance

to what ancient astronaut theorists describe

as mysterious entities called shadow people.

An extraordinary experience has been reported

by thousands of people worldwide.

They're asleep, suddenly they wake up,

and there's this dark humanoid figure that's opaque.

It appears to be made of some ethereal substance

that reflects no light.

MIKE RICKSECKER: Shadow entities can be a lot of different things.

But in general, what we see with these shadow entities

are some common traits, such as no facial features.

Everything is black and dark in nature.

Some may be very solid, some may be very translucent,

but we're not getting any detail.

NARRATOR: Due to their shadowy nature,

experiencers have difficulty making sense

of just what these entities are.

But for most, the encounters are terrifyingly real.

Los Angeles, California.

February 2011.

On a quiet night,

journalist Paul Christensen is asleep in bed

when suddenly, he's jolted awake

by a jarring physical sensation.

It was like being chained to the bottom of the ocean.

You can't move, you can't breathe.

You open your eyes, and there is a presence in the room with you.

You can't make out who it is, what it is.

It looks like...

just a dark entity.

The air behind them--

I don't know how to describe this--

it's kind of fuzzy, it's kind of moving.

And then I was just trying

to make something move or come out of me,

and it ended in just the most bloodcurdling scream

that I could get out of my mouth.

-(screams) -As soon as I screamed,

my girlfriend that was laying next to me woke up,

and I turned the light on...

...and it was gone.

NARRATOR: Paul is uncertain how long the encounter lasted,

but it was only the first of several

that would take place over the next five years.

Each left him paralyzed with fear.

CHRISTENSEN: At the time these were happening,

I was frightened for my life.

Part of me feels like

there's some kind of demonic presence around them.

I've never felt that they were there for good intentions.

It's always come with a heavy feeling of darkness...

...that they were there for something

other than anything good.

NARRATOR: While Paul's encounters with shadowy beings

have left him frightened and desperate for answers,

his experience is not unique.

In 2001, author Heidi Hollis released The Secret War,

in which she shared her own startling experiences

with entities she called shadow people.

HEIDI HOLLIS: I don't even know how to describe that level of fear,

because it was absolutely hulking over me.

And this started my whole journey

into the topic of shadow people.

I'm a person that's not afraid

to say I've experienced something.

I'm like, bring it out into the light, and let's talk about it.

From the start, when I finally got the book published in 2001,

thousands of people from around the world,

from priests to schoolteachers, have written me seeking help.

So my goal is to try to help people to understand

that you can keep these things at bay.

NARRATOR: According to Heidi's research

collecting and studying people's encounters,

these dark entities can appear

as various shapes and figures.

The experiences that I receive often involve a person

waking up, and they feel a presence is in the room.

And if they spot it,

the thing comes even closer and pins them down,

and they're paralyzed.

They often come at nighttime because your guard is down,

so they're taking advantage of you

when you're not at your best.

So, they're sneaky, they're deceptive,

and they evoke a lot of horrific things

into people's lives.

NARRATOR: The dark, humanoid appearance of shadow beings

has caused some to identify them as apparitions or ghosts.

But many researchers believe the shadow people

are a much different type of entity.

A ghost is a human spirit

that is taking some sort of corporeal form.

With a ghost, we get a lot of detail in the apparition.

We can see facial features.

We can see clothing. We can see details in the hair.

Where with shadow entities, we get almost nothing.

NARRATOR: While many psychologists

continue to dismiss the phenomenon

as a symptom of sleep paralysis,

researchers point out that people have reported

encounters that happened when they were wide awake.

In my own personal experience with the shadow people,

I was getting ready to go to sleep, sitting up in bed,

and all of a sudden, this black humanoid figure

enters into the room, walks across the room.

I follow it and watch it, and it just vanishes.

I didn't experience any fear.

I was totally perplexed by what I've seen

and thought, "Wow, what was that?"

HOLLIS: Believe it or not,

the first shadow people experience that I had

was witnessing it following another friend of mine

in broad daylight.

And I saw this entity, this big, hulking black mass--

it kind of looks like a man

with its head directly connected to its shoulders--

going tree to tree

and bush to bush as we're walking along.

And I was just beside myself.

The whole way that we go, we see this thing.

I really thought, you know, I just witnessed

one crazy thing, and that was it.

I trust myself, and I know what it is I experienced,

and I know what was going on.

NARRATOR: If the so-called shadow people are not merely

a trick of the mind but very real

and possibly dangerous entities,

what exactly are they?

Perhaps further clues can be found

by examining similar accounts

that were recorded thousands of years ago.

NARRATOR: Choctaw Nation, Oklahoma.

This nearly seven-million-acre territory

is home to Native people who have occupied North America

for more than 4,000 years.

The Choctaw continue to carry on the centuries-old traditions

of their ancestors to this day.

And one story that continues to loom large

is that of the Nalusa Chito,

which the Choctaw describe as a shadow being.

This Nalusa Chito

is a demonic entity.

And the Choctaw believe that if you're having bad thoughts,

that this will attract the Nalusa Chito to you.

YOUNG: The Nalusa Chito

would get you by creeping inside you

and eating your soul.

The Choctaw were so afraid of this creature,

they would not say the name.

And many people would move along and abandon huts and things

because of the fear of this shadow figure.

BIRNES: We see the shadow people

in the stories of other Native American people.

On Native American reservations,

particularly the Jicarilla Apache reservation

in Dulce, New Mexico,

they talk about the shadow people

as if they are their regular companions.

The legend is this.

If a shadow person, who's really a spirit, sees you

and that shadow people attaches itself to you,

it will be with you for the rest of your life.

NARRATOR: The traditions of these Native American tribes

originated centuries ago.

And as ancient astronaut theorists point out,

accounts of shadowy entities can be found in the legends

of ancient cultures all around the world.

While there are stories of shadow people in modern times,

what I find interesting is

there are also references to what seem to be

shadow people in ancient texts,

and frankly, they're very strange accounts.

Shadow beings go far back into antiquity,

all the way back to the time of ancient Sumer,

where, in that culture, you see accounts of Alû,

which is a type of udug,

which, in their culture, was a type of demon.

Now, Alû, in the way that he would appear to people,

it was very much like our shadow entities of today

where he was very dark in nature.

He had no facial features, no eyes, no nose, no mouth,

and he would hover over people at night.

YOUNG: Of course, there are many accounts of demons

in the scriptures,

the Christian Bible, the Talmud.

In Jewish lore, there is the shadow of death

or the death shadow.

There is this idea that there are

malevolent spirits that could harm you.

NARRATOR: Commonly compared with the shadow people

is an entity known in Islam as the djinn,

supernatural creatures that are often invisible

and have the ability to shape-shift.

The derivation of djinn comes from an Arabic, uh, root,

J-N-N, which literally means to hide or to conceal.

The djinn are created of smokeless fire.

Our English word "genie,"

you know, the mythical spirit that lives inside of a lamp,

comes from the word "djinn."

RICKSECKER: The djinn are considered more trickster in nature.

They have some interesting abilities,

such as they can instantly transport

from one place to another.

They also seem to appear very dark and shadowy in nature,

that they were these big, looming type of characters

when they enter the room.

As a Muslim, you know, I believe the djinn to be real.

Djinn can be angelic.

They can be demonic.

And so, this idea is

that you have to be careful with them

because they are these powerful figures.

They are these literally supernatural figures.

And so, across the Muslim world,

in the present day, particularly in places like North Africa,

you may wear an amulet.

You may have things to ward off the djinn.

You may have, you know, certain things

that you do to protect you from the djinn,

because the idea is that the djinn,

when they're in their demonic capacity,

will do things that can be harmful

or tormenting to human beings.

What I find fascinating is that you have a myriad of cultures

from all over the world

that have very, very similar beliefs

about these shadow entities.

Now, they may call it something different,

but you see in Turkey the Karabasan, the dark presser,

as a very, very similar entity

as to the kana tevoro in Fiji

as to the Pisadeira in Brazil.

They're all talking about the same type of being,

the same type of entity,

and it calls into question, how are these beings visiting

all of these different cultures from all over the world

since they did not have any contact with each other?

GEORGE NOORY: Historically, since the beginning of time,

we have had creature stories of strange beings,

of shadows, of the bogeyman.

And they somehow echo some of the reports

that we're hearing today.

They're somewhat similar.

I don't think they've ever gone away.

They're still here on the planet.

NARRATOR: Have separate cultures around the world

and throughout history

been haunted by the same dark figures?

And if so, just what kind of entities are they?

Perhaps further clues can be found

by examining eyewitness accounts of strange energy

when face-to-face with shadow people.

NARRATOR: Virginia City, Nevada.

October 28, 2016.

Researcher Michelle LeBaron and a group of colleagues

are investigating reports of a shadowlike entity

at a historic saloon called the Washoe Club.

RICKSECKER: She and another woman

ventured into one particular room.

And between her and her friend,

this large shadow loomed up.

She described it as about six-five, six-six in height.

But, again, very, very dark in nature,

so there was no detail.

At one point, she thought

it had completely engulfed her friend,

and they ended up screaming and running out of the room.

Now, this woman,

a few minutes later, after they collected themselves,

walked back over to the hall,

and there stood again this very tall, dark shadow,

but it started doing something very unusual.

There was this pulsating energy

that was emanating forth from it,

like a "whoop, whoop, whoop."

And she could hear it as well as feel it.

In many cases, people feel a certain energy

projecting out from these beings.

And in this particular woman's case,

it was this pulsating type energy.

With other people, it may be more constant.

So, people are experiencing different types of energy

from these beings but, with each of them,

energy nonetheless.

JASON OFFUTT: I have interviewed people

who have encountered shadow beings,

and they've heard what sounded like electricity buzzing.

Uh, and-and the sound would disappear

when the shadow people left the room.

RICKSECKER: There was another woman I interviewed

who saw a flash of light

out in her hallway, and all of a sudden,

this shadow man ran into her room,

jumped on top of her

and pressed her down into the bed.

And the shadow man jumped back off,

ran back out into the hallway,

and she saw another flash of light.

The next morning when she woke up,

she noticed that

all the electronics in that room had been absolutely fried,

and she had to call the fire department

for them to come and inspect everything.

NARRATOR: In addition to hearing and feeling surges of energy,

witnesses often report another curious detail

about the shadow people:

the appearance of glowing eyes.

HENRY: A lot of the shadow people have

no facial features whatsoever. Just blackness.

But some do have glowing eyes,

and, in particular, it's the one with the red glowing eyes

that appear to be the most malevolent.

OFFUTT: When it comes to shadow beings with eyes,

especially blazing red eyes,

people also experience a fear

that is deeper than just "there's an entity in my room."

And they feel that these entities

are-are up to nefarious means.

NARRATOR: So many reports of shadow encounters

are associated with pulsating energy,

glowing eyes and electronic disturbances

that researchers wonder if some shadow entities

might actually be misunderstood technology.

HENRY: It's often discussed

that powerful alien technology can influence

human electronics and technology.

This is definitely something that is reported

with the shadow people experiences.

RICKSECKER: There's also an interesting idea

in which these extraterrestrials may be using

some sort of cloaking device

to hide themselves from our view.

But since they may not quite understand

the physiology of our eyes,

it comes off more of like a shadow.

So, what we may be seeing

is an imperfect type of alien technology.

OFFUTT: I've interviewed two different people

who have described to me what sounds like it could be

some sort of cloaking technology.

One person in particular said that he saw a cloak open

and saw beyond the disguise.

And what he saw, he said, was reptilian scales.

Uh, I-I spoke with someone else who saw something similar

but described the skin as more, like, slick.

Like a... like a frog's but gray.

TSOUKALOS: Could it be

that we're not talking about shadow people

but some type of a technology

that appeared like a shadow and it maybe...

You know, sometime a technology did not work,

it would reveal that person underneath the cloak

or underneath the device.

And so they will be seen

for maybe a fraction of a second.

NARRATOR: For ancient astronaut theorists,

the notion that the shadow people

might be some form of misunderstood technology

is an intriguing possibility.

But what many consider an absolute certainty

is their connection to extraterrestrials.

As evidence, they point to the many accounts

linking the shadow people phenomenon

and alien abduction.

There are a lot of common denominators

with people who experience shadow figures

and those who are abducted.

You wake up in the middle of the night.

You are taken by surprise.

You are paralyzed.

You cannot move. You cannot speak.

You are helpless.

You feel that this entity has taken over you.

It is projecting some sort of energy

that you cannot control.

In my professional, uh, experience

as an investigative reporter

talking with maybe about 3,000 people

in the abduction syndrome over about four decades,

one of the common experiences

that you will hear from abductees

is that they feel paralyzed

in the presence of something in their room,

usually an entity.

A few call them shadow people.

In March of 1991,

in my mail, I received an envelope

that contained illustrations and an audio cassette

and a letter from a woman

who lived in Porterville, California.

And part of the story was her encounter

with shadow people.

And I would like to read a little bit about what she wrote.

"I was in bed asleep when something woke me up.

"The room was filled this time

"with an orange glow,

"and at the center of the room was a hole,

"out of which two well-formed, seemingly three-dimensional

"solid shadow people were stepping.

"The two shadow men grabbed me and pulled me toward the hole.

"That is the last I remember.

"And later, I realized that the little guy,

"the Grey guy that I call the creep,

"was standing off to the right,

"watching my reaction to the whole thing.

He also seemed to be in charge of what was happening."

NARRATOR: Could the accounts of alleged alien abductees

reveal that reports of shadow people are, in fact,

extraterrestrial encounters?

Perhaps further clues can be found

by examining a shadowy being often encountered

by UFO witnesses,

an entity known as the Hat Man.

NARRATOR: Shadow people witnesses

often describe the entities they encounter

as appearing vaguely humanoid with no discernible features.

But in some accounts,

they take a curiously recognizable form.

RICKSECKER: One of the most mysterious types of shadow entities

is what people refer to as the Hat Man.

This type of entity

may be wearing a fedora-type hat

with an accompanying trench coat.

It may be a top hat with or without the cape.

We don't see a lot of detail with the Hat Man.

We see that vague outline.

OFFUTT: The Hat Man appears just like any other shadow being.

There's no definition. You-you can't see,

uh, a nose, a chin, uh, the eyes.

You see the outline of a fedora.

RICKSECKER: Many times, people report

these hat-wearing entities

coming into their bedrooms at night, sometimes flanked

by two humanoid type of shadow entities.

And they strike fear

into the person there lying in bed

and, like an energy vampire,

feed off of that fear.

HOLLIS: There's confusion out there

between different entities.

Something I once called Hat Man shadow,

he is not a shadow person.

He can take on different forms, yes,

as far as being able to blend into a shadow.

But he could step out, and he could be very solid,

so he's a very different type of entity.

But people think he directs the shadow people.

So, shadow people are essentially minions to Hat Man.

NARRATOR: Could reports of the so-called Hat Man

shed new light on the shadow people phenomenon?

Perhaps further clues can be found by examining

one of the very first reported encounters

with these dark entities.

Bridgeport, Connecticut.

1953.

Albert K. Bender,

the nation's top UFO investigator,

receives a threatening visit

that will bring his research to an abrupt and premature halt.

RICKSECKER: Albert K. Bender founded

the International Flying Saucer Bureau.

This was during the big UFO flap of 1952

when flying saucers were witnessed over Washington, D.C.,

and many other areas around the world.

And this organization blew up big

within that first year.

However, just a year later, he suddenly ended

the International Flying Saucer Bureau,

and people wondered why.

And what happened was that he came home one night,

went into his bedroom,

and suddenly these three dark, shadowy figures

materialized through his wall into his bedroom.

They were wearing the hats and the overcoats.

They had glowing eyes, and they smelled like sulfur.

NARRATOR: According to Bender, the three entities

communicated with him through telepathy,

warning him to discontinue his UFO research

and stop publishing his influential magazine,

the Space Review.

Afterwards, he became ill

and didn't eat for three days.

HENRY: After this experience,

Bender was repeatedly visited, he said.

They gave him headaches,

they-they controlled him telepathically,

and he ultimately gave up his UFO researches

and stopped publishing the Space Review,

in which he documented UFO sightings

throughout the world.

He told the people that had been subscribers

and he was working with, "They told me,

"'We come from a very, very far distant place

"'in this universe.

"'And we have been coming and going

"'from your planet for some time,

"'and we cannot allow you

"'or anyone to interfere.

"'And, in fact, we have taken many humans

"'from this planet

to cover up our operations until we are done.'"

RICKSECKER: This is a very influential point in our history,

especially in the ufology community,

in which shadow entities interfered

and thwarted somebody's research

and possibly set the field back a number of years.

NARRATOR: The visitors Albert Bender encountered

match descriptions of what is today known as the Hat Man,

but he called them by another name:

the Men in Black.

While the Men in Black are often portrayed in pop culture

as government agents,

many who claim to have encountered them

believe they are something other than human.

HENRY: The Men in Black are

mysterious and nefarious entities.

They're shadowy. They wear black clothing.

Many people believe that they're either extraterrestrials

or somehow, they're working for extraterrestrials

to prevent humans from learning the truth

about extraterrestrials on Earth.

OFFUTT: They talk to UFO witnesses.

Some people have reported

they seem to not know things that are common,

like, you know, which end of a pen to use.

Or, uh, if they're offered something to eat or drink,

they don't know how to eat or drink it.

HENRY: Both the Hat Man and the Men in Black

are known for wearing a hat.

They both influence people telepathically.

They both appear to be sometimes malevolent,

and they could, in fact, be the same type of a being.

There's a theory that the Hat Man

and the Men in Black are actually the ringleaders

of the shadow people

and that, in fact, they direct the shadow people

to influence humans in particular

to keep them from investigating UFO experiences.

NOORY: There's no question

that the stories of shadow people,

Men in Black and other visitations

are all mixed in together.

Are they the same? Possibly.

But what I think what is really happening on this planet

is mass hysteria

of real events that are happening to real people,

and they can't understand what's going on.

Who knows what's happening?

NARRATOR: For ancient astronaut theorists,

the wide variety of reported shadow people encounters

makes finding an explanation for the phenomenon

all the more difficult.

But some researchers suggest

that we may come closer to the answer

by asking the question,

"Where do they come from?"

NARRATOR: One of the most common and most curious observations

reported by shadow people experiencers

is that these entities are able to make

physical contact with them

but then often disappear

as though they are merely holograms.

OFFUTT: Generally, the shadow people will leave the room.

Either they will dissolve in a puff of smoke

or they will walk through a door.

And they may or may not be material,

have mass, have structural form.

And there's been talk about maybe they come

from some other dimension.

We take for granted that we live in a three-dimensional universe.

The quantum theory makes possible higher dimensions.

Think of fish living in a pond, for example.

The pond is two-dimensional.

The fish are stuck in a two-dimensional world.

They cannot visualize a third dimension.

But you could lift one of these fishes

into the third dimension, and they'd be shocked.

Shocked to realize there's a whole universe

in the third dimension beyond their pond.

Well, we physicists, some of us believe that we are the fish.

We spend all our life in a three-dimensional pond

thinking that that's all there is

when right above us,

there could be higher dimensions,

hyperspatial dimensions up to 11.

RICKSECKER: Theoretically, we have up to 11 dimensions,

and there may be other entities and other life-forms

living within these dimensions.

Now, how would they look to us

if they crossed over those dimensions

and entered into our world?

Well, maybe a shadow entity

is one of these interdimensional beings

that has crossed over from some other place in space-time

into our world.

And we're seeing them as a shadow

because their energy and their personal resonance

doesn't quite adhere

to the energy and the resonance of our planet.

NOORY: If shadow people exist,

and it's very possible that they do,

I think they're coming from other dimensions

within our universe.

I think there are entities that somehow leak through

because some of them even look disoriented,

like they-they don't know where they are.

Somehow, they're coming through another dimension

into ours,

and we're stuck with them.

NARRATOR: Could it be that shadow people experiencers

are witnessing entities

that are capable of traveling between dimensions?

According to ancient astronaut theorists,

there is evidence

that certain places on Earth act as interdimensional portals.

RICKSECKER: We see shadow entities

in these certain locations around the world

in which they seem to appear more often.

There are locations around our planet

where there's more of that Earth energy

that is rising out of the ground.

You know, Stonehenge, the pyramids,

Carnac, places with that ancient energy

that's rising from the ground.

Now, an interdimensional being may be using those locations

to enter into our domain.

NARRATOR: Some researchers believe it is also possible

that shadow people

can alter the human mind

to see into other dimensions.

BIRNES: Ancient peoples believe

that shadow people have the ability

to enter a person's mind

and change that person's perception

so the person can see the spirit.

They've entered from their world into our world.

NARRATOR: According to ancient astronaut theorists,

the notion that the human mind can be altered

to access other dimensions

is supported by experiments

with a powerful hallucinogen called dimethyltryptamine,

or DMT,

the active ingredient in ayahuasca.

This South American drug

is traditionally used throughout the Amazon

to produce intense visions.

Between 1990 and 1995,

scientists at the University of New Mexico

administered DMT to 60 volunteers

and were surprised

to find that many of them had very similar visions,

including encounters with strange beings.

One of the greatest scholars about the effect of DMT

and human beings and what we see in the other world

is Terence McKenna.

Terence McKenna explained

that the strangest thing to him was

those who'd taken ayahuasca generally saw the same thing.

What did they see?

Little green people.

People like Terence McKenna

are saying that's the entrance to another world,

another dimension.

And we know, he says,

that it has a separate existence from us

because people from all different walks of life

see the same thing.

HENRY: These beings appear to be coming

from higher or lower realms

and entering into our physical realm,

perhaps to demonstrate that we, too,

can cross over into these realms.

It's very important that we understand the nature

and origins of these beings

because it could be that they are gonna lead us

to innumerable different species that exist in our universe

as well as how we, too,

can cross over into these other realms.

NARRATOR: Experiments with electric stimulation of the brain

have also caused people to have unexplainable encounters.

OFFUTT: There was a study

done, uh, in-in Sweden

where these scientists put electric charges

in certain parts of the brain

just to see how the subject would react to them.

And a young undergrad was sitting there with a notebook,

and when they increased the voltage

to a certain part of her brain,

she started pulling away

from something that wasn't there.

And afterwards, uh, when she was asked

by the scientist to describe what was going on,

she said that she saw a shadow entity behind her.

And when the voltage was at its highest,

she said it was trying to take the notebook and pen

out of her hands, and she was jerking

to keep it from removing them.

So, is it some part of our brain

that needs an electrical charge

or some charge from ayahuasca

to help us see what's already there?

Very possibly.

NARRATOR: Are shadow people witnesses

encountering entities from other dimensions?

Some ancient astronaut theorists

suggest there is an even more profound explanation:

that just outside the range of human perception,

Earth is inhabited by a great multitude

of otherworldly beings.

NARRATOR: The dark, hulking figure

that comes in the night and paralyzes its prey

remains the most common shadow people experience.

But reports of these entities appearing in broad daylight,

as well as other types of shadow people accounts,

make it difficult for investigators to pin down

exactly what this phenomenon is.

When it comes to the different types of shadow entities,

their behavior, to me,

differentiates one from the other.

The ones that don't pay any attention to people at all,

they could be interdimensional.

The ones that are spying on us could be extraterrestrial.

The ones that instill fear

could be demonic entities.

So, even though they look the same,

generally, I-I don't think a lot of them are.

HENRY: The multifactorial explanation makes a lot of sense.

It could explain why some of them instill fear

and some of them don't,

why some of them appear during daytime

and some of them only appear at nighttime.

The fact is we just don't know enough

about the shadow people,

and a lot more research needs to be done.

NARRATOR: While answers remain elusive,

one popular new theory is that the shadow people

exist outside the limits of human perception,

not occupying an alternate dimension

but vibrating at a frequency

we are not normally able to perceive.

TSOUKALOS: It's a scientific fact

that the human eye can only see certain things.

For example, we cannot see the infrared light spectrum.

So you have to wonder if shadow people operate

in a spectrum that we humans simply cannot see.

And perhaps there are certain people

whose brains operate in a different way,

and they're able to process

more of the reality that we currently experience.

CORY: There are other spectrums that continue on

past our physical brain and our physical self.

And so, why is it so difficult

to imagine that these entities could be existing?

That these entities exist

in these other spectrum

and tap into our spectrum

at will and upon command.

RICKSECKER: I think the benefit for mankind

in learning about these entities...

I think we'd get a better understanding of our universe

and how everything in this universe is connected.

You know, I to you.

Us to the planet, the planet to the Sun

to the solar system to our galaxy.

Everything is interconnected. We're all made of stardust.

And I think we'll have a better understanding

of our origins

and where we're going in the future.

TSOUKALOS: One can argue,

"Oh, it's just a figment of their imagination."

But some of these people have experienced this

for their entire lives.

And I think that we need to investigate

and listen to the people who tell us these stories.

NARRATOR: Is it possible

that humankind shares the Earth

with other intelligent beings

that only a select few are able to perceive?

Perhaps the next step in humankind's evolution

will not involve the development of spacefaring technology

but an expansion of consciousness,

allowing us to see for the first time

that we truly are not alone,

even on our own planet.

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