Original subtitles

(camera shutter clicking)

>> NARRATOR: They hide in the

shadows...

>> OFFICER: Lock your doors,

lock your windows.

>> NARRATOR: ...hunting people

for sport.

>> ERIC HICKEY: He'd put the

victim in handcuffs.

And once that happened, it was

over.

>> NARRATOR: And they hide...

in plain sight.

>> ROBERT SBERNA: Nobody

suspected what he was hiding

in his house.

>> KAREN KUZMA: Each day, for

weeks, they kept bringing

bodies.

>> NARRATOR: But just who...

>> REPORTER: The Son of Sam...

>> REPORTER 2: Jeffrey Dahmer...

>> REPORTER 3: Christopher

Dorner...

>> NARRATOR: ...and what

is a serial killer?

>> CLINT VAN ZANDT: A serial

killer is a totally different

breed of person.

>> NARRATOR: Why do they kill?

>> HELEN MORRISON: We can't

see them.

We don't know them.

We can't identify them.

>> KUZMA: It's still all

a mystery.

>> NARRATOR: There are those

who believe in the existence

of a book.

A book that contains the most

highly guarded secrets of the

United States of America.

A book... whose very existence

is known to only a select few.

But if such a book exists,

what would it contain?

Secret desires?

Secret identities?

Secret... victims?

Does there really exist

America's Book of Secrets?

>> NARRATOR: February 12,

2013.

Big Bear Lake, California, 100

miles northeast of Los Angeles.

Police units surround a cabin

where former LAPD officer and

alleged killer Christopher

Dorner is hiding.

>> CHIEF CHARLIE BECK: Of course

he knows what he's doing.

We trained him.

Ah... he was also a member of

the armed forces.

It is extremely worrisome and

scary.

>> NARRATOR: Sheriffs' deputies

fire incendiary tear gas into

the cabin, setting it on fire.

But rather than surrender,

Dorner places a gun to his head

and takes his own life.

>> JOE DOMANICK: The manhunt for

Christopher Dorner was

absolutely amazing,

unprecedented.

A million dollar reward, police

alerted and looking for him in

20 different counties all the

way down to Mexico.

Never seen anything like it in

Los Angeles, I don't think any

place in the country.

During the entire search for

him up at Big Bear Mountain,

he was hunkered down in a condo

not more than a hundred feet

from where the police had

established their headquarters

for the search.

>> NARRATOR: Christopher

Dorner's innocent victims

included Monica Quan, her

fiancé Keith Lawrence,

Officer Michael Crain and

Deputy Jeremiah MacKay.

>> DOMANICK: Christopher Dorner

was a serial killer.

The definition of a serial

killer is somebody who kills

two or more people at a

different time, in a different

location.

That certainly fits Christopher

Dorner.

But he wasn't your classic

serial killer.

With Dorner it was far deeper

than that.

This wasn't somebody who did it

without motivation.

His motivation was that he

thought he was deeply wounded

and deeply wronged.

>> HICKEY: Most people who

kill only kill once.

But with serial murder, there is

a lot of forethought given to

it.

And each murder, they get better

at what they do.

And so if they get past three

or four victims, then they

pretty much learn how to do it.

And they get really, really good

at it.

>> NARRATOR: Before going on

his deadly rampage, Dorner

posted a rambling manifesto

on Facebook.

It included a hit-list of more

than 50 targets.

>> DOMANICK: Narcissism and

control are two of the character

traits for serial killers, and

certainly that fits what

happened to Dorner.

He lost his job, he lost his

career.

And the narcissism... well, he

posted this... this manifesto!

The fact that he thought his

story was so important that it

had to be told shows the

grandiosity of his fantasy life.

>> NARRATOR: But when the smoke

cleared around Dorner's deadly

mountain hideout, the public was

haunted by one persistent

question...

why?

What causes a seemingly normal

human being, like Christopher

Dorner, to engage in serial acts

of murder?

And what are the secrets trapped

in the minds of America's serial

killers?

Since the 1970s, the United

States has produced an estimated

1,400 serial killers... more

than double the combined total

of the rest of the world.

Recent statistics show that

approximately nine out of ten

serial killers are men, and

although those with high IQs--

such as "The Unabomber" Theodore

Kacyznski-- use explosives to

carry out their carnage, serial

killers with average

intelligence are more likely to

strangle, stab or shoot their

victims.

(gunshot)

But regardless of gender, the

vast majority are driven by one

simple motive: the thrill of

taking another person's life.

>> MORRISON: Serial killers will

talk about how they like to

watch the fear and the pain.

They also like to watch the eyes

as they're dying and watching

the light go out of their eyes.

>> VAN ZANDT: A serial killer

is a totally different breed

of person.

For a serial killer, it's

meeting a need.

If you're in the wrong place at

the wrong time, you can become a

victim without any linkage

whatsoever.

Except perhaps the way you part

your hair, your gender, or just

your path crossed with this guy.

>> NARRATOR: Between 1980 and

2008 there were approximately

185,000 unsolved homicides in

the United States.

And while murder rates have

fallen, the number of cold case

killings in America has

increased to 6,000 a year.

Just how many of these unsolved

murders might be at the hands of

serial killers?

And are they exploiting the very

tools Americans rely upon for

travel and communication to find

their victims?

According to the FBI, there are

as many as 50 active serial

killers operating in the United

States at any one time.

But how can they be identified--

and stopped-- before they

strike?

Is there a secret to detecting

those who kill just for the fun

of it?

>> VAN ZANDT: Serial killers

are much harder to catch,

because normally there's no

linkage, there's no connection

between the killer and the

victim.

And therefore it's much more

challenging for law enforcement

to link multiple murders to one

person.

>> HICKEY: The number of serial

killers are on the rise,

currently, in the United States.

We know that there are actually

women who are also serial

killers.

Certainly there are a lot of

white men who do serial murder.

>> VAN ZANDT: I think because

of television today, and movies,

we've been led to believe, okay,

these are lower-class white

males, uneducated, average IQ of

about 93.

Ah... no, no.

Proportionately, based upon

what they represent in our

population, we see Asians,

we see Hispanics, we see

African-Americans.

>> NARRATOR: October 29, 2009.

Cleveland, Ohio.

In the east side working class

neighborhood of Mount Pleasant,

police force their way into the

home of Anthony Sowell.

They are unprepared for the

horrors that await them inside.

(indistinct radio transmission)

>> SBERNA: As soon as they open

the door there was a horrific

stench that came out of the

house and hit them.

It's dark inside.

The lead officer sees two shapes

on the ground.

Not sure what they were.

So they draw their gun, about

to yell, "freeze," and he

realizes they're dead bodies.

(sirens wailing)

(indistinct radio transmission)

They found two more bodies in

the third floor crawlspace.

They got a hit on some clumsily

repaired wall, found two bodies

in there.

They found another body in a

shallow grave next to the house.

They did a grid search of the

yard.

They found four more bodies.

Inside the house, they found a

red bucket with rodent marks

around the rim.

Inside they found a plastic bag

and a skull was in the bag.

The final death count was 11.

>> NARRATOR: Neighbors were

shocked to learn that a serial

killer was secretly at work in

their midst.

>> SBERNA: He seemed like a

charming, helpful, quiet,

former marine.

Nobody suspected what he

was hiding in his house.

>> NARRATOR: How was the

Cleveland Strangler able to

escape the attention of

authorities as he secretly

murdered 11 women over a

three-year period?

Was he the beneficiary of the

once widely held belief that all

serial killers are white males?

Or was he just good at looking

normal and average?

And could this be how he and

other serial killers can go

undetected for years?

>> VAN ZANDT: Serial killers

look like any of us, therefore

they look like all of us.

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: We can't see them.

We don't know them.

We can't identify them.

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.

And that's what makes them so

very, very dangerous.

>> NARRATOR: December, 2010.

Long Island, New York.

While searching for a missing

person off Ocean Parkway in

Suffolk County just outside of

New York City, police discover

the remains of 11 dead bodies.

>> DOMANICK: The Suffolk County

police found out that they had

a serial killer.

These bodies, um, had been

dumped off this highway since

1996.

The only distinguishing thing

that we know about these

killings is that the police have

no leads at all.

>> NARRATOR: 11 bodies and no

suspect?

Could there, perhaps, be a

secret method serial killers

use to avoid detection?

(camera shutter clicking)

>> VAN ZANDT: A serial killer,

it's like he or she gets a shot

of emotional heroin.

They commit the crime, it meets

the need they have, but after

awhile that itch starts, and

they're out prowling, stalking,

looking for their next victim.

>> NARRATOR: In a nation of

nearly 340 million people, just

how many might be serial

killers?

And is there a secret profile

that can help police and law

enforcement officials detect

them?

>> VAN ZANDT: A portion of any

population, uh, can be

identified as sociopaths,

psychopaths, antisocial

personalities, but some of these

individuals, if you take those

sociopathic tendencies-- the

ability where you can't

empathize with somebody else's

pain, who doesn't look like any

different than anybody else--

you take those two sides of a

personality and meld them

together, you've got a serial

killer.

>> NARRATOR: But what makes a

killer a serial killer?

Is there a certain motive or

method to their perverse crimes?

>> 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.

But one victim, the second

victim, the third victim,

are all so similar-- all

men, all women, all children.

There is no deviation from

their typical victim.

>> HICKEY: A serial killer sees

a victim hitchhiking.

That's a type of victim he's

looking for.

Some serial killers only kill

prostitutes, strangers.

They go for the easiest prey.

There are other serial killers

who prefer more difficult prey

and so they go after college

students.

>> NARRATOR: One of America's

most infamous serial killers,

Ted Bundy, was also known as

the "Campus Killer."

During the late 1970s he

murdered at least 30 women

across seven states.

>> STRAND: Ted Bundy was very

media-genic.

He was a handsome young man.

He'd been a law student.

He was the kind of guy that

women would want to bring home

to the parents.

And yet, here he was, sneaking

around Seattle with his

Volkswagen, with the seat

removed so that he could

transport bodies.

>> NARRATOR: Bundy's victims

were all white, female college

students, mostly with long

straight hair, just like that of

a former girlfriend who had

earlier rejected him.

>> HICKEY: He liked young women

who looked like they were going

someplace; they were

self-confident.

He-he liked the hunt.

He was a true predator in

every sense of the word.

>> NARRATOR: If "The Boy Next

Door," Ted Bundy, thought his

preppy good looks could help him

escape detection, it didn't

work.

On January 24, 1989, the

"Campus Killer" was permanently

expelled-- executed in an

electric chair.

Ironically, there were many

women-- and a few men-- who

wept.

>> HICKEY: Even at the end

when, after being caught and

he's doing his trial, he's

representing himself, even

the judge liked him.

The judge even wished him well

after he gave him the death

sentence.

>> JUDGE EDWARD COWART: You're a

bright young man.

You'd have made a good lawyer.

I'd love to have you practice in

front of me, but you went

another way, partner.

>> HICKEY: Quite amazing for a

judge to do that, but he did.

>> NARRATOR: But what caused Ted

Bundy-- a seemingly successful

member of society-- to engage

in mass homicide?

And are there secret methods and

tools criminologists can use to

help them profile and identify

serial murderers?

Apparently, there are.

And one of them is known as

the Macdonald Triad.

>> HICKEY: The Macdonald Triad

is the belief that we can

identify certain things in

childhood that will then predict

certain types of future

behavior.

For example, the three types are

enuresis, which is bedwetting,

animal cruelty, and fire

setting.

>> VAN ZANDT: Those three

traits or characteristics are

probably common in about 40%

of serial killers-- all three.

But what about the other 60%?

Anybody who ever says they have

a lock on human behavior is

either a fool or a liar.

>> NARRATOR: July 22, 1991.

Milwaukee, Wisconsin.

Police officers respond to a

complaint at the Oxford

Apartment complex.

They arrive at apartment number

213, and are greeted by a man

who lets them in to search the

premises.

His name?

Jeffrey Dahmer.

>> HICKEY: They went toward his

bedroom and when they opened

the door, his bedroom was full

of body parts.

He had torsos and heads here and

there, and arms.

And he was behind them.

Can you imagine suddenly

realizing that the person you're

talking to is behind you and in

front of you are all these body

parts?

>> NARRATOR: The police make

more sickening discoveries:

a 57-gallon vat of acid...

photos of grotesquely mangled

bodies...

and inside the refrigerator...

bags of partially eaten organs,

including a human head.

In all, the apartment contained

the remains of 11 human victims:

Men and boys who police later

determined had been strangled,

dismembered and even eaten by

the man who soon became known as

"The Milwaukee Monster."

>> JUDGE: Mr. Dahmer, you are

charged with four counts of

first-degree intentional

homicide.

Do you understand that?

>> DAHMER: I understand,

Your Honor.

>> MORRISON: You would look

at-at Jeffrey Dahmer-- as you

would every other serial

killer-- and say, I'll go with

this person because they seem to

be fine.

The presentation is one of

a completely non-threatening,

mild-mannered individual that

you don't need to be afraid of.

>> NARRATOR: How did Jeffrey

Dahmer evolve into a serial

killer?

Did he reveal signs of his

deviant fantasies to family or

friends?

And if so, could they have

prevented or even stopped his

secret descent into madness?

In 2012, two decades after

Jeffrey Dahmer was arrested,

graphic novelist-- and former

Dahmer classmate-- John Backderf

published My Friend Dahmer,

a grim series of illustrated

stories chronicling the future

serial killer's high school

years.

>> BACKDERF: When I draw Dahmer,

he just wasn't comfortable

in the world, and I try to

capture that-- you can see the

blank expression, the dead eyes.

>> NARRATOR: In his youth,

Jeffrey Dahmer revealed a clue

into his dark soul by callously

killing and then dissecting

small animals-- one of the

three warning signs identified

in the Macdonald Triad.

>> BACKDERF: He had a clubhouse,

where he kept roadkill that

he found around the

neighborhood-- small animals.

And he would keep them in pickle

jars.

Toward the end of high school,

some neighborhood kids

discovered a dog skull on a pole

in the woods and later we

found out, of course, it was

Dahmer.

I never felt like I knew Jeff.

I don't think anyone knew him.

Sometimes monsters just happen.

>> HICKEY: He had a desire to be

with people who had been buried.

And he was attracted to statues

and mannequins and dolls.

And so this led him to become

sexually involved with these

corpses.

Then he started desecrating

the bodies and cutting them

open and he started

cannibalizing them.

>> WOMAN: I could kill you!

>> JUDGE: Lunch and recess.

>> WOMAN: I could kill you!

>> MORRISON: We try to make

sense of something that seems so

primitive and so out of the

ordinary.

A human being eating another

human being?

He doesn't see his victim as

a human being.

It's just a piece of meat.

>> NARRATOR: According to

criminal profilers, psychopathy

is a personality disorder.

People afflicted with it display

superficial charm,

cold-heartedness and a complete

lack of remorse.

But are all psychopaths serial

killers?

>> HICKEY: Psychopaths feel a

sense of power and control by

being in charge of someone

else's life.

Across the spectrum of

psychopathy, there are probably

three million people out there

who are moving in that

direction.

There are white-collar

psychopaths who get into fraud.

Then there are sexual predators

who are psychopaths.

And then there are those

psychopaths who are serial

killers.

But at the core of psychopathy,

it's always about control and

power.

>> NARRATOR: Wichita, Kansas.

February 25, 2005.

>> OFFICER: BTK is arrested.

(cheering)

>> NARRATOR: Dennis Rader,

the self-proclaimed BTK

killer, for "Bind, Torture and

Kill," is finally apprehended

after more than a 30-year reign

of terror in America's

heartland.

From 1974 to 1991, Rader killed

10 innocent people in the

Wichita area.

And, according to reports, he

was preparing to take his

11th victim just months before

police arrested him.

>> VAN ZANDT: Four of which

were committed on the very

first night.

So here you have someone who

committed a mass murder the very

first time, and then evolved

into a serial killer.

>> JUDGE: Is this something you

were doing for your personal

pleasure?

>> RADER: Uh, sexual fantasies,

sir.

>> NARRATOR: Like most serial

killers, Rader was able to

escape the attention of law

enforcement for decades by

hiding in plain sight.

>> HICKEY: He was married, had

a family, and so people didn't

suspect him.

They didn't think he was that

kind of guy.

>> NARRATOR: But if serial

killers like Rader appear

well-adjusted and normal, is

there really no way of detecting

them... no secret method that

would help the innocent know

to stay away?

>> HICKEY: He liked to

psychologically and physically

torture victims.

Sometimes telling them, "I might

kill you, I might not kill you.

We'll see."

>> RADER: She got sick, threw

up.

I got her a glass of water...

comforted her a little bit...

and then eventually strangled

her.

>> NARRATOR: After murdering

seven people between 1974 and

1977, Dennis Rader did something

equally shocking: he took a

prolonged hiatus from killing.

>> HICKEY: He had a job working

for the city, where he went

around enforcing city

ordinances.

He could tell people what to do;

issue fines to people,

citations.

He liked doing that because it

gave him control.

It also gave him an opportunity

to stalk people.

So he was always looking for

people who he might find as

suitable victims.

>> NARRATOR: After eight years

of silence, BTK's obsession for

murder resurfaced.

Between 1985 and 1991, he killed

three more victims.

But once again, he stopped.

And once again... the trail went

cold.

>> VAN ZANDT: This was his

secret, only he knew, you know?

Nobody else knew who he was.

>> HICKEY: He had distractions

he created for himself.

And he just stopped killing.

And then eventually he realized

he was never going to get

caught.

>> NARRATOR: But in 2004,

Rader's murderous obsession

eventually led him back

into the open.

>> MAN: Tonight, BTK is

back and somewhere in Wichita.

>> WOMAN: And good evening.

Tonight, now that we know

BTK is back, the city is

anxious and fearful.

>> MAN: A letter sent to the

Wichita Eagle is believed to be

from the serial killer.

>> VAN ZANDT: Why didn't Rader

just retire as a serial killer,

go down to Florida, sit on a

beach and laugh about how he

scammed law enforcement?

He starts sending mementos

from his crimes to the

newspaper, to law enforcement.

He wanted people to be afraid.

He wanted to terrorize

that community.

And he had stopped killing

decades before.

He would have gotten away.

We would have never known

who he was, but he just

couldn't let it go.

This arrogance, this feeling

of superiority existed in him,

and that was reason he was

ultimately caught.

>> NARRATOR: April, 1987,

Middletown, Ohio.

Donald Harvey is finally

apprehended after a 17-year

killing spree.

The self-proclaimed "Angel of

Death," Harvey preyed on

the sick and elderly at various

hospitals in the Midwest.

>> VAN ZANDT: Donald Harvey was

a male nurse whose target-rich

environment happened to be

his patients.

>> HICKEY: There were some

suffocations... but primarily he

used cyanide and other poisons

to kill them.

He himself was not a powerful

person physically.

He went to hospitals, where he

could be powerful...

where he could control them and

kill them...

he could act out those fantasies

over and over and over again.

And because they were killed in

the hospital, often there

weren't any autopsies being

done.

So he got away with it.

>> NARRATOR: Donald Harvey was

eventually convicted of killing

37 people...

although he stated that the

actual body count could have

been closer to 90.

But could such an incredible

claim be true?

Are there many more American

deaths at the hands of serial

killers than we know of?

And is it possible this fact is

being kept... a secret?

>> VAN ZANDT: For the serial

killers of this world, they're

not going to stop at one or two

or five... sometimes 500,

sometimes victims are into the

thousands over the years.

>> MORRISON: The secret of a

serial murderer is that they're

not human.

They have no concept of what

death really is.

When they kill, they're not

killing a human being, they're

killing an object, they're

killing something that has no

meaning whatsoever.

>> NARRATOR: But if serial

killers can so seamlessly blend

into the fabric of society, how

can law enforcement stay ahead

of the carnage?

Can science...

forensics...

psychiatry...

or even genetics help us to

identify them...

before it's too late?

>> NARRATOR: Each day, millions

of people rely upon America's

vast network of roads to travel

to and from their destination...

unaware that they may be

secretly watched by a serial

killer.

(camera shutter clicking)

>> STRAND: There is an epidemic

of serial killing going on, on

the American highways.

(indistinct radio communication)

The Interstate Killer.

The Corridor Killer.

There are three people who are

known as the I-5 Killer.

There are literally dozens of

people who are murderers

associated with the highway

system.

>> NARRATOR: In 2004, the FBI

publicly revealed a shocking

secret.

They admitted they were

investigating an estimated 500

unsolved murders committed along

or near America's highways.

And the majority of the 200

suspects are men working as

long-haul truckers.

>> STRAND: The job definitely

provides an opportunity.

It creates a landscape, the

anonymous landscape of the truck

stops, with an endless supply of

women.

>> HICKEY: They can pick up a

victim in one state, kill her in

a second state and dump her in

a third state.

(indistinct radio communication)

>> STRAND: We don't have enough

information yet to know whether

people who are prone to serial

killing are being drawn into the

profession of trucking, or

whether there's something going

on in trucking that's pushing

people who are sociopathically

inclined over the edge.

(truck engine starts)

>> NARRATOR: Is it possible that

the pressures of trucking, or

the unique nature of the

profession, provides not only an

opportunity but a reason for

highway murders?

And if so, could there be other,

perhaps even logical, reasons

why serial killers continue to

exist in our society?

(gun blasting)

>> DOMANICK: Dorner thought that

his dismissal had everything to

do with racism.

I have no doubt that Christopher

Dorner felt he was righteous in

what he was doing.

He was delusional.

>> NARRATOR: But if logic--

or reason-- doesn't explain a

serial killer's deadly motives,

is there another, perhaps

biological reason why some human

beings have a twisted desire

to kill?

Could there be a serial killer

gene?

December 21, 1978.

Chicago, Illinois.

Pursuing a tip about a missing

person, police arrive at the

home of construction worker

John Wayne Gacy.

The search of his home leads

police to a diabolical

discovery.

>> HICKEY: When law enforcement

went into the basement to

investigate, the earth was

moving, shaking everywhere,

because there were millions of

worms eating the bodies.

It was one of the most horrific

crime scenes in American

history.

>> NARRATOR: To his family and

friends, Gacy was a pillar of

his community.

He was married, owned his own

business, and even entertained

children by dressing up and

performing at parties as a

clown.

Yet behind the friendly makeup

lurked the secret desires of a

sadistic killer.

>> VAN ZANDT: He would offer

young boys jobs for his

construction company.

He was bringing these boys,

individually, back into his

house, committing unspeakable

crimes.

>> HICKEY: 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.

>> KUZMA: I mean, 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.

>> NARRATOR: 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.

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.

>> NARRATOR: Was there a secret

biological reason why John Wayne

Gacy committed his hideous

crimes?

Did his brain possess a mutated

gene, a clue that might help

doctors and law enforcement

detect serial killers

before they strike?

Unfortunately, after much

careful study, a team of medical

professionals concluded that

Gacy's brain showed nothing out

of the ordinary.

>> MORRISON: Having looked at

the slides of the brain, seeing

absolutely nothing abnormal, now

the thought was, "It's a dead

brain."

We needed to be able to study

the living brain of a serial

murderer.

>> NARRATOR: At the University

of California at Irvine,

neuroscientist Dr. James Fallon

studies the brain scans of

convicted killers.

>> FALLON: I've looked at them,

and saw for the first time

that there was a pattern

that all of these killers had.

The pattern is a loss of

activity in a part of the brain

called the limbic system.

That's the area of the brain

that regulates not only

impulsivity but also moral

reasoning, ethics.

>> NARRATOR: But what causes

this unusual pattern?

Could it be environmental

stresses?

Abnormal genes?

Or a deadly combination of both?

>> MORRISON: We have no idea

what a serial killer gene might

be.

We're not close at all.

But the other thing is, what if

we do find a gene?

What do we do with that child?

What do we do with that

adolescent?

We can't put somebody in jail

for what they might possibly do.

It brings up a whole ethical

dilemma.

>> NARRATOR: Is science

ultimately incapable of

identifying a serial killer

gene?

And if so, could there be secret

legions of other serial killers,

capable of striking at any time?

Without reason...

without warning...

and without any ability to be

stopped?

>> NARRATOR: July 7, 2010.

Los Angeles, California,

Superior Court.

Suspected serial killer Lonnie

Franklin, Jr., a former

sanitation worker and mechanic

for the Los Angeles Police

Department, is charged with ten

counts of murder.

Franklin is accused of killing

seven women from 1985 to 1988,

and three more between 2002 and

2007.

His 14-year break between

murders gave Franklin the

terrifying title of the "Grim

Sleeper."

>> DOMANICK: When the police

went to his home, they found

thousands of photos of women,

many of them in very

compromising positions.

And they believe that the term

"The Grim Sleeper" might be aer, and tha

was doing this all the way

though to the present.

>> NARRATOR: In 2012, th

>> NARRATOR: In 2012, the LAPD

created a Facebook page that

included 42 Polaroid images

recovered from Franklin's home.

They are seeking the public's

help in identifying what could

very well be hundreds more

victims of this predatory

murderer.

But while the Internet provides

a tool for law enforcement...

it may have also been the very

same tool the killer used to

lure his unsuspecting victims.

>> HICKEY: We've had serial

killers who have actually

attracted victims online to

their homes, where they've

killed them.

We had one case in Missouri

where women were killed and

placed in different metal drums

before that killer was actually

caught.

>> NARRATOR: Chat rooms...

dating sites...

and social media forums.

Could the Internet really be the

latest mask that serial killers

wear to hide in plain sight?

Has it become their latest

secret weapon?

>> HICKEY: Serial killers today

are becoming more

sophisticated, because they have

so many different tools that

they can use to create

distractions and to create

ruses.

The internet has really opened

up the opportunities for serial

killers to find victims more

easily.

>> NARRATOR: Just what is the

connective thread that binds

serial killers like Ted Bundy...

Dennis Rader...

John Wayne Gacy...

and Christopher Dorner together?

And, if we find it, could it

explain why the United States

produces more serial killers

than any other country in the

world?

>> HICKEY: Any country has the

capacity to produce serial

killers.

But there's some environments,

some cultures, like American

culture, where we almost

encourage it.

>> MAN (over TV): Lock your

doors, lock your windows.

>> MAN 2: Who wants to be next?

I don't, no one else does.

>> HICKEY: We also make movies

about them.

Hollywood does influence people

in its movies.

People get ideas.

There is information that's put

out there on television and so

forth.

And we know that serial killers,

as mass murderers do, they learn

from each other's experiences.

And so some might get better at

it.

(commander shouts orders)

>> DOMANICK: Dorner was not a

product of the LAPD, he was a

product of a wider American

culture.

(reporters clamoring)

A media-saturated culture.

What we're seeing now with

serial killing is one serial

killing leads to another serial

killing that leads to another

serial killing, because you have

your moment of fame...

and you go out like a shooting

star.

>> STRAND: In my research,

looking at, uh, serial killers

in the United States, there was

frequently a kind of class

anxiety.

They saw themselves as oppressed

when everyone else was

successful.

I find it concerning that

inequality seems to be such a

factor in driving certain kinds

of individuals over the edge.

>> NARRATOR: Will economic

insecurity...

(protestors chanting)

...social unrest...

>> MAN: I'm a innocent victim.

>> OFFICER: Let's go.

Yeah, we all are.

>> NARRATOR: ...and an

increasingly fragmented society

lead even more psychologically

disturbed individuals to become

full-fledged serial killers?

And if so, can anything be done

to stop the impending carnage?

Perhaps the ultimate answer lies

within ourselves... and the

secret desires we hide from

each other every single day.

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