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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