All language subtitles for The.UnXplained.S03E09.Serial Killers

Shatner:
Driven by their darkest urges,

sadistic predators
stalk their victims

in an effort to satisfy
their need to kill.

The horrible deeds
done by serial killers

give us a glimpse into the minds

of humanity's
most disturbed individuals.

But what is it that separates
so-called normal people

from those who have
an insatiable desire

to take a life?

(gasps)

that is what we'll try
and find out.

♪ ♪

detectives with cadaver dogs

discover the badly decomposed
remains of several women.

They are found stuffed
inside industrial barrels,

on a farm belonging
to john edward robinson.

In 1993, during the early days
of the internet,

robinson, under the alias
"slavemaster,"

prowled chat rooms
in search of potential victims.

He then lured them
to his property.

As a gruesome consequence
for his crimes,

john edward robinson received
the dubious distinction

of being the internet's
first convicted serial killer.

The internet has really
opened up, uh, the opportunities

for serial killers to find,
um, victims more easily.

We've had serial killers
who have actually

a-attracted victims online

to their homes,
where they've killed them.

Across state lines.

They've offered work.
They've offered sex.

"come to my home
and I'll give you money."

you know, one has to be
very careful on the internet,

'cause you can be what--
whoever you want to be.

And so, serial killers
do find victims that way.

-(barks)
-while searching
for a missing person

just off ocean parkway,
in suffolk county,

a police officer
and his dog discover

the skeletal remains
of a dead woman.

Police later find that
ten more mutilated bodies

have been disposed of
in this area,

and all in a similar fashion.

Joe domanick: The suffolk
county police found out

that they had a serial killer
in their midst

when they started
finding bodies dumped.

And really,
the distinguishing thing

that we know
about these killings

is that the police found out

that many of them
were prostitutes.

Shatner:
As news of these shocking
discoveries make headlines,

the unknown murderer
becomes known as

the long island serial killer.

And once the bodies
are identified,

another eerie coincidence
is discovered.

Several of the victims
had offered escort services

on the internet site craigslist.

Hickey:
Craigslist is another mask.

It's another way to use
social media to find victims.

And, uh, it's another tool
in their repertoire.

So, in some ways,
serial killers today

are becoming more sophisticated.

Psychopaths feel
a sense of power and control

because they have
so many different tools

that they can use
to create distractions

and to create ruses.

Narcissism and control

are two of the character traits
for serial killers.

Certainly that fits
for serial killers

who prey on women
on the margins.

Shatner:
Even though the suffolk county
police have offered

a $25,000 reward for information

leading to an arrest
in the long island murders--

the largest offered
in the county's history--

to this day,
the killer remains at large.

But what compels someone like
the long island serial killer

or john edward robinson
to commit cold-blooded murder

again and again?

What makes an otherwise normal
human being a serial killer?

A serial killer is defined
as someone who kills

three or more people

with an emotional
cooling-off period in between.

Whereas a mass murderer

will come in and kill
three people at the same place.

And a spree killer,
he will kill,

move onto the next, kill again,

move onto the next, but there's
no emotional cooling-off period.

A serial killer, it's like

he or she gets a shot
of emotional heroin.

Shatner:
The term "serial killer" was
first coined in the mid-1970s

by former fbi psychological
profiler robert ressler.

He picked the word "serial"
because police described

these types of murders
as being crimes in a series.

Serial killers are repetitive

because there are things
that drive them.

There's a fantasy involved
with-with the killing.

This is especially true
if we're talking about

sexual predators
who are serial killers.

Judy ho:
They just don't seem to have
their emotions stimulated

the way that
a normal person's brain would.

They just think about what's
gonna feel good right now,

and they don't routinely take
other people's feelings

into consideration,

and engaging in all those
analytical consequences

and functions
that people think about.

Harvey rosenstock:
You don't have any kind
of conscience at all,

whether it's one murder
or two murders or three murders.

The person who is committing
a crime and another crime

and another crime,
the only deterrent,

the only place where he has
some qualms, some regrets,

is if, in fact,
he does get caught.

Van zandt:
The fbi has said there's
maybe 50 serial killers

operating in the united states
at any one time.

Do we have a lock
on who they are? Well, no.

They would be under arrest
if we did.

We don't know who they are.

We can't identify who they are.

We don't know that
they're a serial killer

until we find the victims
that they've killed.

We also know that when
we find them, the big secret

is that we will never be able
to rehabilitate them.

Shatner:
If serial killers
are so difficult to profile,

and nearly impossible to detect,

is there any way
we can ever feel safe?

Perhaps the answers can be
found by examining the case

of america's very first
serial killer,

and the sadistic lair
that he called

the murder castle.

An estimated 27 million people
from all over the world flock

to the world's
columbian exposition,

otherwise known as
the chicago world's fair.

It is so named in honor
of the 400th anniversary

of christopher columbus's
landing in the new world.

Having risen from the ashes
of the great chicago fire,

the city now shines
brighter than ever,

illuminating the fairgrounds

with nearly
100,000 electric lamps.

-But...
-(footsteps echoing)

lurking in the shadows
is a sadistic killer...

...Herman webster mudgett,

better known by his alias
h.H. Holmes.

Morrison:
H.H. Holmes was
extremely clever.

He was a pharmacist, actually.

His home was set up
for single women

who came to the city to make
their way, to get involved,

to become part of this wonderful
exposition that was going on.

So h.H. Holmes had access
to many, many single women...

...And he murdered them.

Hickey:
Holmes had spent
a great deal of time

in preparation for his murders.

It wasn't like
it was on impulse.

There was a lot of control here.

I think that he enjoyed

the, uh, power he had
over people in general.

And the world's fair
really played out well for him.

Shatner:
Holmes became rich

as a cunning
and charismatic con artist.

He swindled several people
out of their fortunes,

and used the proceeds to build
a one-of-a-kind mansion

which allowed him to pursue
his darkest desires.

The macabre edifice
would eventually become known

as holmes's murder castle.

H.H. Holmes built
this phenomenally complex castle

with enough rooms that he could
rent rooms to people

who came in for the exposition,
mostly single women,

and he would go out
and advertise this,

bring people in,
put them in these rooms

where they felt they were safe.

It was almost like
the spider to the fly.

It was like,
"come and see my mansion,

an elaborate mansion."

he had all kinds of
odd staircases

-and tunnels
and chutes and things.
-(woman screams)

so then he would gas
these victims

and then send them down
the chute into the basement.

And then torture them,
or if they were already dead,

then he could take-take apart
the bodies and-- which he did.

Shatner:
On November 17, 1894,

the man known as
america's first serial killer

was finally arrested,

but only then did investigators
begin to learn the full extent

of h.H. Holmes's
murderous behavior.

After confessing to the murders
of 27 young women,

on may 7, 1896, holmes,

now referred to by the press as
"the devil in the white city"

was hanged by the neck
until dead.

But what led an otherwise normal
and unassuming man

to not only commit murders
but to construct

such an elaborate
house of horror?

Perhaps the answer can be found
by exploring the lair

of yet another serial killer,

one created
almost a century later.

Shatner:
Police officers
responding to a complaint

arrive at the apartment of a man
by the name of jeffrey dahmer,

apartment number 213.

But what happens next
defies explanation.

Hickey:
When the police arrived
at his apartment,

they went toward his bedroom,
and when they opened the door,

his bedroom was
full of body parts.

Torsos and heads here and there.

Shatner:
The police made
even more shocking discoveries:

A 57-gallon vat of acid,

photos of
grotesquely mangled bodies,

partially eaten organs,

and inside the refrigerator,
a human head.

In all, the apartment contained
the remains of 11 human victims,

men and boys who police later
determined had been murdered,

dismembered and even eaten

by the man
who soon became known as

the "milwaukee monster."

jeffrey dahmer was
a serial killer

who usually chose his victims,
uh, in young men,

usually around
their teenage years.

He would usually find a way
with drugs or alcohol and sex

to compel victims
to come back to his apartment,

where he would murder them.

Many times,
he'd cut up the bodies.

He would save pieces of the body
in his freezer

and his refrigerator.

Hickey:
The stench of a decomposing body

is absolutely overwhelming,
and yet,

dahmer became acclimated to it.

His fantasy was-was

to make this table,
which he, which he built,

and he took the heads
of some of his victims

and placed them on the desk,

where he could sit
and be surrounded

by all of these skulls
of people that he had eaten.

These were his friends;
these were people he loved

in his own fantasy world.

Judge: Mr. Dahmer,
you're charged with four counts

of first-degree
intentional homicide.

-Do you understand that?
-I understand, your honor.

Shatner:
Like h.H. Holmes before him,
jeffrey dahmer was not content

with the mere taking
of human lives.

Instead, he sought to construct

the equivalent
of a virtual world--

an alternate reality dedicated
to his deviant fixations.

But what causes an otherwise
average and unremarkable man

like jeffrey dahmer to become
a bloodthirsty serial killer?

One person who believes
he may have

at least a few of the answers

is graphic novelist
and former dahmer classmate

john backderf.

In 2012,

nearly two decades after dahmer
was beaten to death in prison,

backderf published
my friend dahmer,

a series of illustrated stories
that chronicle

the future serial killer's
high school years.

Backderf: We went to junior high
and high school together,

and were friends from age 12
to when we graduated.

He was always
a pretty strange dude,

kind of an oddball,
and he got darker and darker

as our time together went on.

Shatner:
In his depictions of dahmer,

backderf sought to reveal the
warning signs that were present

in the young,
troubled man's demeanor.

Backderf:
When I draw dahmer,

I try to capture the blank
expression, the dead eyes.

I purposely make him look
uncomfortable in his own body,

because that's
how I remember him.

He was kind of, like, robotic,

like he didn't physically fit in
with the rest of humanity,

which, of course, he didn't.

Jeff was very much
a blank canvas.

You never knew what was going on

behind this blank wall
of a face.

And of course, that's
something that later became

a very lethal trait,

because his victims
had no idea what was coming.

Part of dahmer's
schoolyard legend

was clubhouse,
where he kept roadkill

that he found around
the neighborhood, small animals.

And he would keep them
in pickle jars.

He would actually dissect
these roadkill.

Shatner:
Was dahmer's so-called clubhouse

a chilling precursor
to apartment number 213,

the place where
his adolescent fascination

with animal carcasses escalated

into an uncontrollable obsession
of dismemberment,

necrophilia and,
most notoriously, cannibalism?

We try to make sense

of something
that seems so primitive

and so out of the ordinary.

A human being eating
another human being?

But this is not a human being,

and he doesn't see his victim
as a human being.

It's just a piece of meat.

Backderf:
I never felt like I knew jeff.

I don't think anyone knew him.

I never dreamed that he would
commit crimes like this.

How is it that we're so unaware

of the monsters
that walk among us?

Shatner:
Does jeffrey dahmer's childhood

suggest that serial killers
develop their dark impulses

early in life?

And if so, then why
aren't we able to spot them

before it's too late?

After more than a decade
of denials,

and mere moments away
from his execution,

ted bundy confesses
to 30 homicides.

(woman screaming)

it was a trail of death
that spanned many years

and stretched from
washington state to florida.

I can only liken it to--
after, you know,

I don't want
to overdramatize it--

but to have been possessed

by something
so awful and so alien,

and then, the next morning,
wake up from it.

Strand:
He was everything,
as the media loved saying,

that you would expect
a fine young american man to be.

The kind of guy
that women would want

to bring home to the parents.

Judge:
You're a bright young man.

You'd have made a good lawyer.

I'd have loved to have you
practice in front of me.

But you went another way,
partner.

Strand:
And yet here he was,
sneaking around seattle,

with his volkswagen
with the seat removed

so that he could
transport bodies.

He was psychopathic.

Shatner: But how could
an otherwise clean-cut

and educated young man
like ted bundy

become a cold-blooded,
psychopathic killer?

Van zandt:
Serial killers
look like any of us;

therefore they look like
all of us.

There are those individuals
that have the ability

to wear the mask all the time.

You can never see
through that mask

until they want you to see it,

and usually that's
when you've become a victim.

Morrison:
When we find them,

we can't figure out
why they do what they do.

How they're able to commit
so many crimes

without being found.

Shatner:
Perhaps an even more
shocking example

of how adept serial killers
can be at hiding in plain sight

can be found
by examining the case of a man

who everyone thought was
a selfless veteran

until they found out what he was
hiding inside his house.

(siren wailing)

shatner:
Police arrive at
the home of anthony sowell

with a warrant to arrest him
for an alleged rape.

Before they even
enter the house,

they get their first hint of the
horror that awaits them inside.

As soon as they open the door of
the house, in the first place,

there is a... A horrific stench.

(flies buzzing)

they get up to the third floor,

and the lead officer sees
dead bodies.

The bodies were so decomposed

that he couldn't even
recognize them as human figures.

At that time,
the county coroner came out,

started taking evidence
from the scene.

It was a long night.

Shatner:
In total, investigators
recovered the bodies

of 11 women,

choked to death by the man
who would become known

as the cleveland strangler.

Sowell committed these murders

over the course
of just two years,

all without leaving his hometown

and without raising
the suspicions of the community.

Sberna:
The neighbors were shocked

that they were living next door
to a serial killer.

He seemed like a charming,
helpful, quiet, former marine.

He was named honor marine
of his boot camp.

Was discharged honorably
as a sergeant.

Nobody suspected what he was
hiding in his house.

It was very important for him
to be seen as a helper.

There were elderly people
in the neighborhood

and single women that he would
perform household tasks for--

mow their lawn, fix their sink.

An individual
who tends to be psychopathic

can have very strong connections
to the community,

and typically is very difficult
to track down,

because it's
a very opportunistic crime.

A person who takes advantage
of a situation on the spot

to do something impulsive.

Shatner:
In hindsight, sowell's efforts
to portray himself

as an upstanding member
of the community

were merely a cover
for his evil side.

According to all accounts,
he was born into a dark world

of both physical
and emotional abuse.

Sberna:
Anthony sowell was
a product of a broken home.

He was raised by
his mother and grandmother

in a large house
in east cleveland.

14 people were living
in that house.

His mother was physically
abusive to the children.

Her favorite targets
were anthony sowell's nieces.

She'd strip them naked,
tie them to a banister,

then she'd whip them
till they were bloody.

From an early age,
he associated sex with violence.

As an adult,
whipping naked women

is exactly the pattern
that he recreated.

So from the earliest time
that he could possibly remember,

there is no foundation
of any kind of real morality.

His mother didn't
particularly feel sorry for him.

Why should he feel sorry
for somebody else?

Shatner:
In the mid-1980s,

after serving seven years
in the marine corps,

sowell returned to
his childhood home in cleveland

and almost immediately found
himself in trouble with the law.

He had some arrests
for drinking,

drug use
and breaking and enterings.

Until 1989. Met a woman.

Brought her home, took her
upstairs to the third floor

where he said
they were gonna party,

and then he raped her violently
over a 24-hour period.

-(woman screaming)
-she's able to yell and scream,

get the attention of neighbors.

She testifies
against him in court.

He goes away for 15 years.

Shatner:
When he was released
from prison in 2005,

anthony sowell
was not only an ex-con

but a registered sex offender.

So, how was he able
to avoid suspicion

and commit murder
practically in his own backyard,

and not once but 11 times?

Anthony sowell would, uh, charm
women with his personality.

There were quite a few people
that had drug problems

living in the neighborhood.

Sowell was fairly popular

because he was the man
with crack.

Sowell's victims were typically
african american females

who had drug problems
and were transient.

Sowell was a prototypical
malignant narcissist,

extremely self-absorbed to
the point of committing murder

to gain whatever
he needed to gain.

Many serial killers
are very charming,

and that's actually how
they get close to their victim,

close enough
to actually do the deed.

Psychopaths are known
to be able to manipulate

their social prowess,
and many of them actually have

very high
emotional intelligence.

It's just that they decide
when they're gonna

use it and when they're not.

(echoing laughter)

morrison:
Their first victim,

we don't know
why they choose them.

We don't know if it's because
they're available

or because they've had
a thought about this.

Out of all the 50 people
that may be in that bar,

why do they choose
that one person

that they know
will go with them?

Why and how do they know

that that individual
will be cooperative?

A lot of people say
it's because they're available,

they're not gonna be missed,
so forth and so on,

but that's too simple
an explanation.

Shatner:
Today, anthony sowell
resides on death row

in chillicothe correctional
institution in ohio.

In addition to the 11 murders
he was convicted for,

sowell is believed
to have carried out

dozens of rapes and assaults

over a period
of more than four decades

before he was stopped.

But did anthony sowell
become a serial killer

because of the abuse he suffered
at the hands of his mother?

Or was he,
as some experts believe,

simply born bad?

Shatner:
15-year-old robert piest

is working the afternoon shift

at nisson pharmacy
when he overhears a customer

say that he's looking for help
with a remodeling job.

It will pay
five dollars an hour,

almost double the pay

that piest makes
at the pharmacy.

At 9:00 p.M.,

robert leaves the store
to get started

for his new employer:
John wayne gacy.

Van zandt:
John wayne gacy
ran a construction company.

And he would
offer young boys jobs

for his construction company,

and, of course,
they wanted to get jobs.

Hickey:
He'd say,
"you're looking for a job?

Come over to my house."

when the victim got there,

he'd say, "by the way,
did I ever show you

the old handcuff trick?"

so, he'd put him in handcuffs

behind his back,
and once that happened,

it was over.

-(siren wailing)
-shatner: Ten days after

robert piest's family
reported him missing,

police arrive
at john gacy's home

and uncover a grisly scene.

When law enforcement
went into the basement

to investigate,

they found 33 bodies
in the basement.

The earth was moving,
shaking everywhere

because there were millions
of worms in the bodies.

It was one of the most horrific

crime scenes
in american history.

Karen kuzma:
During the daytime,

he led a life
of running a business.

And then at night,
during a period of years,

he apparently went out
and killed these men.

And how often? Nobody knows.

It's still all a mystery.

Shatner:
Between 1972 and 1978,

john wayne gacy

murdered at least
33 teenage boys and young men.

But perhaps even more disturbing

is the fact
that often during the murders,

gacy liked to dress up
like a circus clown.

It was a character
he had created

for fundraising events
and children's birthday parties.

Gacy's deceptions
were so effective

that he once even had
his picture taken

with rosalynn carter,

the first lady
of the united states.

John gacy was extremely active
in his community.

He would give parties,
barbecues,

200 people,
for all of his neighbors.

Shatner:
But looming beneath gacy's
baby-faced grin

and child-friendly persona
was a deeply troubled man

who was plagued by a toxic mix
of childhood trauma

and mental defects.

My dad was a drinker.

John was always criticized
by my father.

He had a learning disability.

He had problems.
They had to take him

and put him in a special school.

My father
would always say to him,

you know,
"you act like a sissy."

you know,
"you need to be more of a man."

my mom told me that john
had been sexually assaulted

when he was around eight
or nine years of age.

John never said a word
about his abuse or-or anything.

It's hard for me to fathom
that john killed 33 young men.

But my brain tells me
he had to have.

(indistinct shouting)

shatner:
On may 10, 1994,

an estimated 1,000 people

gathered in
the early morning hours

as the man now known
as the killer clown

was executed
by lethal injection.

But in the wake of his death,

one last question
had to be considered.

Could john wayne gacy's
dark impulses

have been genetically hardwired
inside him?

Kuzma:
I think everybody
tries to figure out

what type of person
is a serial killer.

Is this something that I have
to worry about with my children

or my children's children?

Is it there in-in the genes,

or is it something
that created a problem?

Shatner:
In an effort to find
a possible clinical explanation

for gacy's horrific crimes,

forensic psychiatrist
dr. Helen morrison,

who had served as
an expert witness at the trial,

made a bold request
of the killer's family.

Morrison:
When gacy was
going to be executed,

I called the family
and asked them

if we could use the brain
for scientific study.

The family agreed.

Kuzma:
I was really into
wanting to know

was there something
genetically wrong with him.

Because, I mean,
there's two sisters.

Neither one of us
have killed anybody.

And we wanted to get
some kind of sense

of what happened, what...

How did he get
this other character in him?

Morrison:
This is the brain
of john wayne gacy.

This is the first brain
that we've been able to get

to look for any potential
difference or change

that might make a serial killer.

Shatner:
But could dissecting

the diseased brain
of a serial killer

really offer
a scientific explanation

for john wayne gacy's
grotesque crimes?

Helen morrison hoped
for a satisfying answer.

Morrison:
Having looked at the slides
of the brain,

seeing absolutely
nothing abnormal,

now the thought was
it's a dead brain.

What is it going to show us

about what's happening
in that live brain?

We needed a living brain.

We needed to be able to study

the living brain
of a serial murderer.

Shatner:
According to dr. Morrison,

the only way
to accurately determine

if a serial killer gene
does exist

is by studying a living brain.

Many brain scans
from psychopaths

show a loss of activity
in the limbic system.

But is this proof that a person
is predisposed to kill?

Ho:
That loss of activity

in the limbic system
really shows

that they have real difficulties

engaging in empathy
as an automatic task.

Although we see
sort of this evidence

for some hardwiring
of psychopaths

in these brain differences,

we also know that nurture
plays a huge role.

So, not every single person

who has sort of these
psychopathic-looking brains

actually turn out
to be psychopaths

in terms of their actions.

They don't necessarily commit
a bunch of crimes.

Shatner:
But what if one day
in the future,

we are able to determine

that a serial killer gene
really does exist?

What would we do with someone
who has that particular gene

but hasn't yet committed
any crimes?

I think the ethical problems
with rewiring the brain

is the issue of the choice
of the person.

When somebody says that you need
to have your brain rewired,

who's making that determination?

And should they be the one
to make that call?

Shatner:
But even if we do eventually
crack the serial killer code

and find out
what compels them to kill,

we still may be powerless
to stop the bloodshed.

Because how do you stop someone
before they commit a crime?

Unless, of course, they want
to be caught in the first place.

It seems most serial killers
can't resist

playing cat and mouse
with the public.

Penning letters to the police.

Leaving clues
at the scene of a crime.

Even drawing maps

to where the bodies
of their victims can be found.

But why?

Are they trying to prove
how smart they are?

Or are they really desperate
to get caught?

♪ ♪

perhaps driven
by extreme narcissism,

grievance or sinister delusions,

some serial killers
are compelled to communicate

with the media
and law enforcement.

Like the zodiac killer,

who sent a total of 21 letters
to local newspapers

that revealed specific details
about his crimes.

Or david berkowitz,

who antagonized police
with handwritten letters

which he signed,
"yours in murder,

mr. Monster."

david berkowitz,

the so-called son of sam killer,

started his murders using
a .44 caliber pistol

in new york city at the time the
united states was celebrating

its 200-year anniversary.

I mean, this was a guy who said,

"look at me,
look at me, look at me.

I'm the monster
that you're afraid of."

and he wanted credit
for his crimes.

Shatner:
But why would a killer

risk being caught
by engaging with

and even taunting the police?

Are they looking
to become famous?

Or is there another,
more twisted reason?

Dennis rader,

a.K.A. The btk serial killer
out of wichita, kansas--

"btk" standing for "bind them,
torture them, kill them."

I mean, this arrogance,
this feeling of superiority

existed in him to the very end.

And that was the reason
he was ultimately caught.

Since she lived
down the street from me,

I could watch the coming
and going quite easily.

Oh, I manually strangled her
when she started to scream.

Dennis rader,
he liked to torture victims,

psychologically
and physically torture them.

-(heavy breathing)
-he would stalk victims.

He'd go to their homes.
He'd hide in the homes.

When people came home,
he would attack them,

tie them up
and then torture them,

sometimes telling them, "I might
kill you, I might not kill you.

We'll see."

of course,
he was going to kill them.

But he wanted them to suffer.
So he's very sadistic that way.

Van zandt:
Rader, over a period
of 20-plus years,

was believed responsible
for about ten murders,

four of which were committed
on the very first night.

So here you have someone
who committed a mass murder,

and he would've gotten away,

we would've never known
who he was,

but he wanted to terrorize
that community.

Susan peters:
Good evening.

Tonight, now that we know
btk is back,

the city is anxious and fearful.

A letter sent to
the wichita eagle is believed

to be from the serial killer.

Dennis rader, he stopped killing
for a long time.

For several years,
he just stopped killing.

And then eventually he realized
he was never going to be caught.

At least, in his own thinking.

And so he came back

and he started giving out
information to law enforcement.

"well, here's what I'm doing.
And I'm still here."

newsman: The serial killer
who terrorized wichita for years

causes new fears.

Van zandt:
He starts sending mementos
from his crimes

to the newspaper,
to law enforcement.

He sent a computer disk
with some memorabilia on it.

The fbi was able to trace
that computer disk

back to the church
where he was an elder.

They were able to identify rader
as a potential suspect.

And the btk serial killer
was eventually caught.

Hickey:
It was like he wanted
to be caught.

He literally gave them
enough information

where they could track him down.

And that's pretty unusual.

Van zandt:
He wanted the reputation
of btk to go on.

And because of that,
because of that need within him,

he was eventually
identified, arrested

and sent to jail for life.

Shatner:
But did the btk killer

reemerge from the shadows
in an effort to become famous

or even infamous?

Or was he really trying
to be stopped

and then punished
for his crimes?

Hickey: There are some,
because of their narcissism,

they want to be recognized
for their murders.

They're in it for the game.

They will play this
all the way through.

They want movies done
about them.

They want books
written about them.

They want to be interviewed.

Because that's the narcissism
in them.

One serial killing
leads to another serial killing

that leads
to another serial killing.

Because you have
your moment of fame,

you go out like a shooting star.

Newswoman: Collecting sports
cards is a big american hobby.

But this may, a new collectible
series will go on the market:

Serial killers
and mass murderers.

Shatner:
There are many who believe that,

for some serial killers,
the desire to be famous

is equal
to their desire to kill.

But, if so, why?

Perhaps the answer can be found
by using the same method

many serial killers now use
to stalk their victims:

The internet.

Shatner:
The internet.

For most of us, it is
a powerful tool that allows us

to get vast amounts
of important information

at the click of a button.

But is it also capable
of making serial killing easier

and perhaps safer for
the killers than ever before?

Not necessarily.

For decades, the infamous
golden state killer,

who committed 13 murders
in california

between 1974 and 1986

and was given several
menacing names in the press,

baffled investigators.

That is, until April 24, 2018,
when authorities charged

72-year-old
joseph james deangelo

with first-degree murder

and identified him
as the golden state killer.

And how did they finally
crack the case?

An investigator uploaded
crime scene dna to gedmatch,

a genealogy website
that allows people

to compare their genetic
information on the internet.

Authorities were able
to connect information found

on the site to one of
deangelo's family members,

which ultimately led the police
to deangelo himself.

But does this mean that finding
and apprehending serial killers

will soon become so efficient

that we will be able
to stop them

before they begin
their reign of terror?

It's a compelling notion
but unlikely.

According to
radford university's

serial killer database,

there have been more than
3,000 confirmed serial killers

in the united states since 1900.

And criminologists believe

that the united states
has produced more serial killers

than any other country
in the world.

But why?

Hickey:
Any country has the capacity

to produce serial killers.

Uh, but there are
some environments,

some cultures,
like american culture,

where there's a tremendous
fascination with serial killers.

Because we all want to be
forensics specialists.

We love to watch all these
crime movies on television.

And it makes us think about
murder in very strange ways.

For most people,
it doesn't create killers.

But it does fascinate people.

I do think it's true

that we're overly interested
in serial killers

in this culture
and that people are fascinated

by these extremes
of human emotion.

Whether that contributes
to copycat crimes,

that is a question
that is-is worth asking.

Shatner:
Is it possible that
our interest in serial killers

is actually creating new ones?

It's certainly
a frightening possibility

but no more disturbing
than the enduring mystery

of what causes a person
to hunt human beings for sport.

(woman screams)

although we know a lot
about serial killers

in the united states,

there's just
a lot about motivation

for human behavior
that we don't understand,

that we don't know.

And that's what allows
these individuals

to stay out there, stalking,
identifying and killing.

Hickey:
There's not one profile that
fits serial killers in general.

But, actually,
there are different types

of serial killers,
based upon their motivations,

uh, and what drives them
to kill.

So, why are humans

so endlessly fascinated
by serial killers?

Are we afraid that we might
become one of their victims?

Or is it something within us
that makes us more afraid

that we could be
serial killers ourselves?

Perhaps that's why we find them
so frightening,

so-so disturbing and so...

Unexplained.

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