Original subtitles

Tonight on "Secrets Declassified"...

experiments considered so wild, dangerous, or deadly,

they have to be hidden from the public.

From building an aircraft carrier made of ice

to defeat Nazi U-boats--

This thing will be

the largest naval vessel ever constructed.

To a manned mission to Mars

that never leaves Earth...

These men are subjected

to every form of stress

that their Soviet overlords can think of.

Or even to Stalin's obsession

with understanding his rivals...

They want to profile Mao by analyzing his poo.

These are the astonishing

and sometimes terrible things done by governments

and the people who work for them.

It's time to bring them to light.

It's World War II.

In the Atlantic, Hitler's U-boats are hunting

British ships relentlessly.

So Britain gambles on a daring experiment--

build an unsinkable ship,

not from steel but from ice.

By 1942, Britain feels like it's against the ropes.

U-boats hunting in the mid-Atlantic

are sinking 650,000 tons

of shipping every month.

The killing zone is called U-boat Alley.

It's a stretch of the mid-Atlantic

where Allied ships are unprotected.

Air Force planes can't reach that far from land bases,

and the British can't send aircraft carriers to help

because they would be sunk by the U-boats, too.

What they need is an aircraft carrier that can't be sunk.

Enter Geoffrey Pyke,

an eccentric adventurer and inventor

now working for Allied HQ.

Geoffrey Pyke comes up with the realization

that nature already produces giant, unsinkable platforms

in the ocean.

They're called icebergs.

So he comes up with the idea

that you could flatten one

and tow it wherever you wanted it to be.

You can use it as an unsinkable aircraft carrier,

and it can close the mid-Atlantic gap.

But Pyke soon realizes icebergs won't work.

They have this nasty tendency to flip,

which would put your aircraft and your crew

in the cold Atlantic waters, so, no,

not a good solution.

Pyke won't be stopped so easily.

He begins to design an artificial iceberg.

Pyke's idea is to create

a giant aircraft carrier,

not from steel but from blocks of carved ice.

He could have a system of cooling pipes

throughout the ice to keep it frozen

and also use diesel engines to propel it forward.

At a secret lab

hidden in a refrigerated storage unit

at London's Smithfield's Meat Market,

Pyke's team starts experimenting.

There's one big shortcoming with ice.

It is extremely brittle.

If it came under enemy attack, it will fracture.

So, as Pyke considers this problem,

he takes some inspiration from reinforced concrete

and the idea that perhaps combining water

with another element

would produce a harder ice product.

Pyke's team begins to experiment

with additives to increase the durability of ice.

They find a research paper

from scientists in Brooklyn, New York,

testing cotton as a reinforcer,

but this makes a slushy, uneven ice block.

Finally, after lots of experimentation,

they come up with just the right recipe,

and that is 4% wood pulp and 96% water.

This combination creates

an incredibly durable block of ice.

Pyke's new ice behaves like nothing else on Earth.

It's strong as concrete and almost bulletproof.

It can be cast like metal and cut like wood.

They name this new miracle material Pykrete,

after its inventor.

British Prime Minister Winston Churchill

is the kind of guy who likes unusual, bold, daring ideas.

So he says, yeah, let's do this.

Pyke's project is given the code name "Habbakuk."

Habbakuk is an Old Testament prophet

who records God's promise to the doubtful.

"I'm going to do something in your days

that you would not believe, even if you were told."

Pyke chooses the name

to fit his impossibly ambitious ice ship.

Now he needs to construct a prototype.

But Britain is too warm to build it,

so the entire project moves to Canada.

They turn the frozen surface of Patricia Lake

into a giant laboratory

and build a 1,000-ton, 60-foot-long scale model.

The Habbakuk team starts experimenting,

and they find that in order to keep the ice stable,

the ship's refrigerators need to keep it

at a frosty 5 degrees.

They also discover that to stop a torpedo,

the hull has to be at least 30 feet thick.

When they complete their design,

it is an absolute behemoth.

Pyke wanted an ice ship

with a runway 2,000 feet long and 300 feet wide.

It has 40-foot-thick walls,

and it can carry over 150 bombers at one time.

This will be the largest naval vessel ever built.

Project Habakkuk

is now becoming hugely expensive,

so it needs American backing.

In August 1943,

at the Allied conference in Quebec,

the Brits make their pitch.

To prove the properties of Pykrete

to the Americans,

one of the UK's top commanders, Lord Mountbatten,

stages a demo.

Mountbatten gives U.S. General Hap Arnold an ax

and asks him to smash a block of Pykrete.

Arnold swings at the Pykrete with all his might.

The ax bounces off.

Then Mountbatten draws his pistol

and fires it at the Pykrete.

The bullet ricochets off,

sending the generals diving for cover.

The room erupts, but the point is made.

The Americans are on board for Habakkuk.

Before production can begin,

the tides turn in the Atlantic.

Long-range aircraft and new anti-submarine tactics

blunt the U-boat threat.

With the crisis over,

the ice ship is no longer needed.

In January 1944,

project Habakkuk is canceled.

The prototype ship they'd built on Patricia Lake

is allowed to melt away.

Soon, the war comes to an end.

The British military keeps details of Pykrete

on ice for the next 30 years.

We only learn the full details

through declassified documents that are discovered in 1973.

They speak to an hour of desperation,

when England faced an existential threat

as a result of the U-boat.

Winston Churchill isn't the only leader

to green-light an audacious experiment.

When the Soviets decide to beat the U.S. to Mars,

three cosmonauts are locked in a test chamber

for a year-long study.

They learn that it's not the equipment that fails,

it's the crew.

In Moscow, leaders are convinced that getting to Mars

will definitively win the Space Race.

For the Soviets, putting a man on Mars

would be a massive prestige win.

But a round trip to Mars would take a full year.

At the time, no one knows whether humans

can survive that long in space.

Moscow's Institute of Biomedical Problems

hatches a bold experiment.

They call it a year in a spaceship,

but they run it at their labs in Moscow.

The plan is to lock up a cosmonaut test crew

for 365 days inside a cramped metal box.

They want to find out

if the team can endure such a long spaceflight

and what the scientists need to do to make it work.

Soviet leadership signs off

on the space-chamber plan.

On November 5, 1967,

the top secret experiment begins.

In order for this experiment

to provide any meaningful results,

the three cosmonauts

are going to have to be actually isolated.

The only contact that they will have

with the outside world

will be through a radio channel,

and everything will be documented on film.

To the men locked inside,

the chamber feels more like a prison cell than a starship.

There is no privacy.

The living quarters are just 10-by-13 feet

and not built for comfort.

The crew has a table, a stove, some medical gear,

and three flimsy fold-out bunks

Soon, the conditions begin to take a toll

on the cosmonauts, and the space chamber

becomes a psychological pressure cooker.

Within a few weeks, all of them are showing signs

of psychological stress.

They're no longer enjoying

any collective activities together.

They seem to be almost at each other's throats all the time.

Within two months,

the crewmen are not speaking to one another.

If they're holding these churlish grudges

against one another, they're not a cohesive team.

They're not an effective team.

With the experiment at risk,

the scientists take action.

They build a 200-square-foot greenhouse

and dock it with the simulated mission.

The greenhouse gives them

a little bit of dignity to get away from one another.

It gives them something positive and constructive

to do with their time.

And, suddenly, rather than being

at each other's throats constantly,

they're back to being a cohesive team again.

With the experiment back on track,

the scientists decide to stress-test the crew.

They simulate a failure

of the chamber's life-support systems.

The Soviet lab administrators

massively raise the concentration

of carbon dioxide in the capsule.

They crank the temperature up to 86 degrees.

They push the humidity to a tropical 90%.

All of the subjects are suffering

from headaches and exhaustion.

It feels like hell in space.

The extreme conditions force the crew to cooperate.

On November 5, 1968,

after a full year inside the space chamber,

the experiment comes to an end.

The most important lesson learned

is that claustrophobia and monotony

are two of the biggest challenges a cosmonaut crew

will face on the way to Mars.

For years, the full details

of the secret space-chamber experiment

remained buried deep in Kremlin files.

It's not until 1975 that they're finally revealed

to the world,

when cosmonaut Andrej Bozhko publishes his memoir.

He actually describes the feelings

that he and his fellow participants had

living inside this tiny capsule for a year.

Although the cosmonauts

never actually leave Moscow,

the lessons learned from the experiment

prove useful for planning future space missions.

If we're going to send somebody to Mars,

you can't just simply put them in a capsule

and expect them to endure a 34-million-mile voyage.

You have to provide more space for them.

Otherwise, the mission is going to fail,

because the individuals are going to fail.

At the start of the Cold War,

the U.S. wants to know more about biological weapons--

how to protect against them or how to use them.

To learn more, the Pentagon comes up

with a top secret experiment.

The target-- unsuspecting American cities.

At the beginning of the 1950s,

the Pentagon is terrified that the Soviets

might launch a biological attack

against the United States.

In the event that such an attack

was released on the U.S., what would happen?

Everything is, at this point, an unknown quantity.

The Army Chemical Corps

is tasked to investigate.

The Chemical Corps considers several options.

The first one they come up with is using a wind tunnel

to see how it disperses,

but that's nothing like real-world conditions.

The second option they consider

is building a city in the desert.

However, that turns out to be too expensive.

And the third option is to do live testing

in real U.S. cities

but, instead of using a real biological agent,

use a stand-in.

They start by looking for a safe substitute

for deadly germ weapons.

Chemical Corps scientists

find this apparently ideal candidate.

It's a fluorescent powder used in TV screens

called zinc cadmium sulfide.

What makes this powder so ideal

is that the individual grain sizes

are very similar to the sizes of the known biological agents

that an adversarial nation may use.

The other thing about them is that they fluoresce

under ultraviolet light,

so it's easy to track them wherever they go.

Initially, at least,

the Army thinks that the substance is harmless.

What they didn't know then but we do know now

is that cadmium is a top-tier carcinogen.

It causes lung cancer and kidney cancer.

In January 1953,

the experiment is ready to begin.

The Army wants to study how a biological agent

would spread through an entire city.

The question is, what city?

The Army needs cities in the United States

to be an approximate match

for corresponding Soviet cities,

in the event that one day the U.S. wants to carry out

some sort of chemical or biological attack

against a Soviet city.

First up is a viable proxy for brutally cold Leningrad--

Minneapolis in Minnesota.

Here, they want to find out how a biological weapon

might get inside different types of buildings.

To cover up what they're doing

and reassure the public, they come up with a story

that they're testing a smoke screen

to protect the city from Soviet missiles.

Local authorities are eager to help, so they sign on.

The Army selects a range of testing locations--

factories, office buildings.

But one site stands out...

Clinton Elementary School.

They mount sprayers on the roof

and release clouds of zinc cadmium sulfide

onto the surrounding building and the playground.

Inside the school, they put detectors

to measure how much zinc cadmium sulfide

is seeping in.

What the Army learns from all of this

is that even during the winter,

when everyone's largely sealed up in interior spaces,

the pathogen is still gonna find its way

into those spaces.

That means there's nowhere to hide

from a biological attack of this sort.

By February 1953,

the Army decides to scale up the experiment.

How would a bioweapon spread across a bigger city...

like Moscow?

They set their sights on St. Louis, Missouri.

The Chemical Corps focuses their experiments

on the Pruitt-Igoe housing projects.

They put sprayers on the rooftops of all 33 towers

and start pumping out zinc cadmium sulfide.

Other sprayers are mounted inside vehicles,

and those squirt out toxic powder while they drive around.

Over two years,

the Chemical Corps sprays more than 2,000 pounds

of zinc cadmium sulfide

over just 10 square miles of St. Louis.

The results are disturbing.

In urban canyons between tall buildings,

wind turbulence disperses the particles vertically.

But in open spaces like parks,

they linger at ground level.

In an attack, some places are gonna be largely spared,

while others are gonna be devastated.

Next, the Army wants to understand the spread

over multiple states,

so it launches its biggest experiment yet,

called Operation LAC-- Large Area Coverage.

An aircraft is loaded with zinc cadmium sulfide,

and it sprays it during a flight

from South Dakota to Minneapolis.

The results are alarming.

That's because they detect particles from that flight

1,200 miles away.

It proves that even with a small quantity

of pathogen distributed in air

can reach a much broader geographical area.

Over the next 10 years, the U.S. Army Chemical Corps

conducts 200 experiments with zinc cadmium sulfide

in a geographical region

stretching from the Rocky Mountains

to the Atlantic Coast, affecting 40 different states.

The Chemical Corps learns that a single tank

of weaponized biological agent can spread disease

to an area three times the size of New York City.

By the end of the 1960s,

the Army has the information it needs.

The experiments are wrapped up,

and the details are buried

under top secret classification.

The Army keeps the experiments hidden for decades.

Then, in 1994, the truth is revealed.

When journalists publish their findings,

the public is outraged and rightly so.

These were experiments done on unwitting Americans,

and the experiments could potentially have been deadly.

The Army maintains that,

yeah, cadmium may be a dangerous chemical,

but the amounts of exposure were so low,

they were nontoxic.

This entire operation

suggests the mindset during that era of the Cold War.

When you're talking about the survivability of the country

in a biological, chemical, or nuclear attack,

there's very little that the U.S. government

was unwilling to do.

At the end of the 1940s, the Soviet Union and China

begin talks over potential alliance.

Stalin wants a deeper understanding of Chairman Mao,

so he sends a scientist into Mao's bathroom.

Communist China's leader, Chairman Mao Zedong,

rolls into Moscow, aiming to forge an alliance

with Soviet premier Joseph Stalin.

Stalin sees Mao as something less than him,

and he has no problem keeping him waiting.

In fact, he keeps him waiting for days.

This insult is a deliberate ploy.

The issue is that Stalin, as is often the case with Stalin,

doesn't trust Mao.

And he's letting him wait for days on end

because he wants to get into Mao's head.

He wants to figure out what makes the man tick.

While Mao waits in Moscow,

Stalin turns to his secret police.

He orders the NKVD to conduct a bizarre experiment,

which will remain secret for over six decades.

He wants them to build

a complete psychological profile of the Chinese leader,

starting in a very unusual place.

It sounds insane, but one of the ways

that they plan to do this is by analyzing who he is,

getting a piece of him, if you will.

They're going to analyze his poo.

For years, the NKVD labs

have been running a bizarre

and top secret experimental program

in scatological research.

That's the study of excrement to gain intelligence.

The theory is simple.

Soviet scientists believe a person's waste

can provide insights into their psyche.

Stalin's team is under the impression

that high levels

of the amino acid tryptophan in the poo

indicate a calm and approachable personality.

The deficiency in potassium could be an indication

of a nervous and unpredictable person.

To run their tests,

the NKVD needs one key thing--

a sample from the chairman himself.

Mao gets invited to the Kremlin

to have talks with Stalin,

but the NKVD makes sure that those talks get delayed

day after day after day.

While Mao is waiting,

the Kremlin staff serve up a series of elaborate banquets

for him and his team--

huge feasts piled high with delicacies.

But this lavish hospitality is a trap.

Really, they're just looking to ensure that the man

has to have a bowel movement there in the Kremlin.

And they have a specially rigged toilet

that they want him to use.

NKVD agents install special collection toilets.

These don't connect to the sewers.

Instead, they funnel the waste into special containers.

It's a dirty trick.

Eventually, the NKVD succeeds in collecting

some of Mao's products.

Once collected,

the samples are rushed to a classified lab

where a team of dedicated scientists

meticulously analyze them.

They test for tryptophan,

potassium, and other chemicals--

things that they ultimately think

are going to be indicative of Mao's moods.

The excrement experiment

is reportedly a success.

The NKVD team sends a detailed...

scatological-psychological portrait of Mao

directly to Stalin.

The report about Mao sent to Stalin

has never been found,

so the details inside it are lost to history.

What we do know

is that after reviewing the scatological profile,

Stalin is said to be scathing

about Mao's communist credentials.

"This man is a radish," he declares.

'He's only red on the outside, but his insides are white."

This makes Stalin very wary

of engaging in any significant partnerships.

The Chinese leader leaves Moscow

with a watered-down treaty,

and none of the financial support he's been hoping for.

Stalin's scatological lab

doesn't last much longer after he died in 1953.

His successors didn't have the same predilections

about analyzing the biochemistry of humans.

The experiment remains classified

for the next six decades.

Then in 2016, former Russian agent Igor Atamanenko

reveals Stalin's obsessions.

He reports that he's found the details

of this poop research

in the declassified files within Soviet archives.

The revelation makes headlines worldwide...

as one of the Cold War's most bizarre experiments

is finally brought to light.

As World War II comes to an end,

millions across Europe are on the brink of famine.

To maintain order,

the U.S. must figure out how to help them.

So, far from the front lines,

the War Department begins an extraordinary experiment--

intentionally starving healthy American volunteers.

By 1944, Allied forces

are ashore in Normandy.

They're driving the enemy,

and they will soon be in Germany itself.

Allied leaders are about to face a new challenge.

Millions of civilians across the war zone

are on the edge of starvation,

and it's gonna be the job

of the victors

to feed them back to health.

To be prepared, they need to understand

how people's metabolism changes

as they experience malnutrition,

and that has never been studied properly.

Enter Dr. Ancel Keys,

a physiologist at the University of Minnesota

and special assistant to the U.S. Secretary of War.

To solve the famine problem,

Keys proposes a dangerous and controversial experiment.

He wants to do a controlled study

under lab conditions

of human starvation and recovery from starvation.

The War Department likes the plan

and gives Keys its backing.

Now he needs volunteers who are willing to starve

for their country.

To get useful results,

Keys wants to use healthy young men for the experiment,

but most of those are off fighting in the war--

but not all of them.

Keys identifies an untapped pool of healthy young men

who are still in the U.S.-- conscientious objectors.

Keys recruits using a brochure

signed off on by the War Department.

On the cover is a picture of starving children,

with the text reading

"Will you starve that they be better fed?"

It's an emotional appeal, but it works.

More than 200 men volunteer.

Keys picks 36 of the healthiest

and most psychologically stable candidates

to be his guinea pigs.

He sets up a facility

literally underneath the bleachers

at the University of Minnesota

so that the men are away from prying eyes.

In February 1945,

the starvation phase of the experiment begins.

To start, he slashes

the men's daily calorie intakes in half.

Keys wants to impose a reduced calorie intake

but also make the subjects burn more energy by exercising.

So he puts them through the Harvard fitness test,

which is a series of exercises that are designed

to push people to the limits of their endurance.

The effects of starvation

are swift and shocking.

The subjects drop around 20%

of their body weight in the first 12 weeks.

Their ribs are sticking out.

They've got no energy. They're just wilting.

One subject gets himself trapped

in a department store's revolving door.

He's just too weak to push himself through.

And it's not just physical.

As the weeks go by, the starving subjects

are getting irritable, they're getting depressed,

and, not surprisingly,

they become totally obsessed with food.

Two men get into a physical brawl

in a canteen line over a scrap of pasta.

That's how complete this obsession with food

becomes for them.

They're fighting even over a couple of scraps.

One individual starts having visions of cannibalism.

He's fantasizing about food,

and he reaches the limits of his mental endurance.

Look at that generous helping

of rich, juicy barbecue.

He actually sneaks out of the study,

goes into town, and engages in a massive caloric binge

in the form of milkshakes and ice-cream sundaes.

After six months,

the starvation phase finally ends.

Next comes the refeeding.

Keys believes that by gradually increasing

the subjects' calorie intake,

he can safely feed them back to health

without triggering any negative reaction.

He splits the subjects into four groups,

and the different groups get different amounts

of extra food.

Some groups are also given extra protein and vitamins,

while others just get the base amount of carbohydrates.

Now a new and dangerous problem arises.

Their body weight continues to plummet,

even though they're renourishing

these test subjects.

Keys discovers that the men are shedding

retained edema fluid

that's been masking just how much weight they've lost.

This is a potential disaster for the study.

To get the experiment back on track,

Keys decides to supersize his portions.

He just doubles the calories for the groups,

and to the relief of the scientific team, it works.

The men finally begin to recover.

Keys realized

that in refeeding a starving population,

vitamins and protein were really a luxury.

It was the calories that mattered.

They needed at least 4,000 calories a day.

Keys passes that information on to the War Department,

who immediately put it to practical use

in post-World War II Europe.

Keys wraps up the experiment

in October, 1945,

but his complete findings remain hidden.

It's not until five years later

that he finally reveals the data in his masterwork--

"The Biology of Human Starvation."

The results of the starvation experiment

are used worldwide in famine relief.

In 1979, Soviet scientists are secretly experimenting

with deadly bacteria.

And when a lab technician makes a simple mistake,

an entire city will pay the price.

The U.S. and the Soviets have signed a treaty

banning biological-weapons research.

The Soviets are looking to get an edge

and have no problem cheating.

They're continuing research

to create even more dangerous weaponized diseases.

In the city of Sverdlovsk,

laboratories at Compound 19 are running 3 shifts a day,

working to develop a killer weapon using anthrax.

Anthrax is a deadly disease

caused by the bacteria Bacillus anthracis.

If inhaled, its fatality rate is up to 90%.

Even a fraction of a milligram can kill.

It's perfect for a weapon

because the spores are tough enough

to be delivered by a bomb

and small enough to disperse after the explosion

as an invisible, lethal mist.

Compound 19's goals are absolutely terrifying.

Inside airtight chambers,

scientists are testing new anthrax strains

in aerosol form on monkeys,

hoping to create a deadly super weapon.

They're attempting to create a new strain

that does not respond to antibiotics.

This work is incredibly dangerous,

not just for the workers

but also for the citizens in the surrounding city.

Compound 19 uses a complex system of filters

to purify the contaminated air

before it gets vented into the atmosphere outside.

The lab's safety system seems foolproof,

but its chain of protection

is only as strong as the weakest link.

On Friday, March 30th, that link snaps.

A technician

is finishing up the afternoon shift

on an anthrax production line.

And he shuts down as normal

before the next shift comes on duty.

He notices that there's a filter that's clogged.

He takes it out.

And he leaves a note letting the next shift know

that, hey, I've taken it out.

This needs attention.

Now, this is where

the safety protocols break down.

The officer in charge fails to make a note in his logbook,

and the technician's note gets lost.

The next shift comes on,

and the anthrax production line gets going again.

The machinery is switched back on.

What the scientists don't realize

is that the critical filter is still missing.

When the plant is restarted

without the filter in place,

it begins to pump out anthrax aerosol

into the cold night air.

A steady wind carries this invisible cloud

of deadly spores

right over the sleeping city of Sverdlovsk.

It seeps into buildings,

getting inhaled by unknowing citizens.

No one realizes for hours that this is happening.

When a technician at Compound 19

finally spots the error...

They shut down the line and replace the filter,

but it's too late.

It doesn't take long

for the anthrax to take effect.

The first victims have no idea what's hit them.

32-year-old Raisa Smirnova

is working at a nearby ceramics factory,

when a co-worker notices her hands are turning blue.

She's rushed to the hospital.

She's feverish, struggling to breathe,

and slips into a coma.

Over the next few days, more people fall sick

with mysterious flu-like symptoms

that progress to respiratory failure

and then to a horrible choking death.

Soon, the hospitals of Sverdlovsk

are overwhelmed with victims.

At least 64 people die.

Local doctors are baffled.

The symptoms are indicative of inhalation anthrax,

but that almost never happens in nature.

When that starts to really sink in...

terror seizes the city.

Kremlin officials

realize that Compound 19's secrets

are about to be exposed.

So they dispatch agents to contain the fallout.

The KGB comes in and enforces a citywide cover-up.

They confiscate patient files.

They take autopsy reports.

They even bring in trucks that spray down the town

with chlorine bleach that turns the trees yellow.

News of that many deaths is bound to leak out,

within the Soviet Union and to the West.

So the Soviet authorities create a cover story.

They say the deaths are caused by gastrointestinal anthrax,

which is easily explainable

by citizens eating contaminated meat

that they bought on the black market.

Moscow keeps the deadly lab leak hidden

for more than a decade.

Then, in 1991, the Soviet Union collapses.

A new Russian president, Boris Yeltsin, comes to power

and soon reveals the truth about the Sverdlovsk incident.

Yeltsin spills the beans.

He's trying to be a good partner

and demonstrate to the West that he's trustworthy,

and he lets it be known that, no, it had nothing to do

with black-market meat.

Harvard bioweapons expert Matthew Meselson

gets permission to investigate further.

He travels to Sverdlovsk.

He tracks down survivors,

and he talks to the families of the dead.

He confirms exactly what Yeltsin's admitted to--

this was caused by military development.

In 1994, Meselson finally publishes

his research paper, and it conclusively reveals

that the Sverdlovsk incident was caused by weapons research

at Compound 19.

That accident caused the deadliest recorded

anthrax outbreak in human history.

After the U.S. dropped two nuclear bombs on Japan,

World War II is over.

But the plutonium core of a third bomb is ready

and waiting at the Los Alamos National Laboratory.

Scientists put it to use there

in experiments that are so dangerous,

they name it the Demon Core.

The war is won, and America's atomic whiz kids

are now working to master the apocalyptic power

they've unleashed.

Louis Slotin is a 35-year-old physics prodigy

working at Los Alamos lab.

He has a pretty impressive résumé.

He's a veteran of the Manhattan Project,

and he's also known as a bit of a cowboy,

both in his style of dress,

as well as his fearless approach to science.

He's doing experiments to understand

how to make the plutonium bomb more efficient.

He is a physicist who is absolutely brilliant,

but he certainly is someone who's willing to bend the rules

if it helps to enhance his persona

as a risk-taker.

In May 1946,

just weeks before he's set to leave Los Alamos

for a teaching job,

Slotin heads into the lab to show his replacement

how to do his signature experiment,

working directly on the leftover plutonium bomb core.

The core is a softball-sized sphere

of weaponized plutonium alloy.

It's so radioactive that it's warm to the touch.

It's so dangerous that it's given the nickname

the Demon Core.

The Demon Core is constantly emitting subatomic particles

called neutrons.

If those neutrons can escape freely,

the core remains stable.

But if those neutrons

are somehow trapped in the core and build up,

it'll become unstable and effectively become a bomb.

His mentor, the nuclear pioneer Enrico Fermi,

warns him about the experiment.

If you keep doing it, you'll be dead within the year.

He keeps on doing it.

The audience is transfixed

as Slotin gets to work on the Demon Core.

To get his data,

Slotin must intentionally edge the Demon Core

toward an explosion,

while trying to stop just short of triggering one.

He lowers a neutron-reflecting

beryllium shell over the Demon Core

and measures how many neutrons start building up inside it.

This is incredibly useful for the scientists

but also incredibly dangerous.

The closer the shell gets to the core,

the closer the core comes to a super-critical state.

If the beryllium shell closes completely over the Demon Core,

the energy inside will build up to super criticality

in a catastrophic instant.

And that means either a burst of radiation

or an all-out explosion.

Los Alamos has rules for everything.

You need to, right?

You're dealing with some of the most dangerous substances

on Earth.

And the regulations Los Alamos puts in place

is to use wooden spacers to keep the two hemispheres

of these shells apart.

Slotin, however, as the cowboy, decides to do it his own way.

Instead of wooden spacers, he uses a flathead screwdriver

to wedge open these two shells

just enough to keep it from going critical.

It's a reckless method, but it works.

In his left hand, he holds the shell of the core,

in the right hand, a screwdriver with a flat tip

just between the two halves of the hemisphere.

After tempting fate,

Slotin's luck finally runs out.

The screwdriver slips, and the shell snaps shut.

There's a silent blinding flash

of blue light,

and then a wave of heat sweeps across the room.

Radiation is expanding in every direction.

Slotin knows it's too late for him to run.

He immediately lunges forward

and rips the beryllium shell off with his bare hands.

His quick decision breaks the chain reaction

and puts the Demon Cores back to sleep.

He saves the lives of the other men in the room,

but it's too late for him.

Being so close to the Demon Core,

Slotin's absorbed a massive dose of radiation.

Slotin's left hand feels like it's on fire.

A sour, metallic taste fills his mouth.

As he leaves the room,

he begins to vomit uncontrollably.

On the way to the hospital,

Slotin turns to one of the observers, and he apologizes.

"I'm sorry I got you into this,

but I have less than a 50% chance of living."

And even that was optimistic.

Over the next nine days,

Slotin's body slowly disintegrates.

He has what's known as three-dimensional burns,

which is essentially a sunburn inside of his body.

He also has gangrene and massive organ failure.

On May 30th, he dies in agony--

a victim of the Demon Core.

Although Slotin's death makes the papers,

for decades, the full details

of his fatal Demon Core experiment are buried

under top secret classification,

hidden for over a quarter of a century.

Finally, in 1989, "The New York Times"

publishes the full story

and reveal the true horror of the Demon Core experiments

to an unsuspecting public.

From toxic tests in black-site labs

to bold ideas that push back

the boundaries of human knowledge,

governments have long conducted extraordinary experiments

in secret.

Though it may take years,

the covert science eventually finds its way into the light.