Tonight on "Secrets Declassified,"
cracking secret codes that win battles and save lives,
from the Pacific, where a U.S. codebreaker races
to prevent another Pearl Harbor...
This code is just about impossible to break.
To Vietnam, where U.S. airmens' escape route is plotted
with clues from an unusual source...
They're gonna use the layout
of his favorite golf courses as a code.
To a housewife in Virginia
that reveals her husband is selling
top secret codes to the enemy.
Tucked away in the closet is a grocery bag
stuffed with classified Navy documents.
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.
The first hole at Tucson National Golf Course
is 430 yards and bends to the left.
The fourth at Abilene Country Club is 195 yards.
They might sound like trivial facts,
but for one U.S. airman shot down behind enemy lines
in Vietnam, they're the difference
between life and death.
On Good Friday, 1972,
the North Vietnamese launch a massive
surprise assault into South Vietnam.
The U.S. Air Force scrambles to launch
a series of tactical air strikes
to try and contain this invasion.
And many airmen who've been looking forward
to some leave suddenly find themselves back on active duty.
One of the unlucky men recalled from R&R
is 53-year-old Gene Hambleton.
Gene Hambleton is a navigator and an electronics specialist
in the U.S. Air Force.
He seems old to still be flying
combat missions, but it's his expertise in jamming
enemy radar that puts him back into the cockpit
heading to North Vietnam.
Just minutes into his mission,
his airplane is struck, and he finds himself
having to parachute into enemy territory.
For the U.S. military,
Hambleton isn't just another man down.
Because of his seniority,
Hambleton has an intimate knowledge
of top secret strategic air command operations.
He cannot be allowed to fall into enemy hands.
The race is on to find Hambleton
before the enemy does.
The Air Force manages to make radio contact with Hambleton,
and they launch one air evac after another.
But the rescue choppers keep getting shot down.
Then the Navy SEALs propose
a different kind of rescue.
Their plan is to covertly sail up the Mieu Giang River
and pluck Hambleton from an extraction point
two miles away from his current location.
There's one big problem.
The survival radio that Hambleton has
allows him to communicate with American forces,
but it also allows the enemy to listen in
on those transmissions.
They're going to need a secret code,
which only Hambleton can understand.
That's a lot easier said than done.
The rescuers reach out to Hambleton's squadron
to find things out about his personal life,
so they can come up with a coded language
that he would understand and the enemy wouldn't.
They discover that Hambleton
is an avid golfer, but not only that,
he has freakishly encyclopedic knowledge
about the world's most renowned golf courses.
Maybe they can encode a route to the extraction point
using the layout
of his favorite golf courses as a code.
It's a crazy idea, but it's the only hope
the Air Force has of getting their man back.
The rescue team starts overlaying
golf course plans over aerial reconnaissance photos.
And they start plotting a route
to the extraction point
across farmland that also stays away from roads
and enemy positions,
and they break that plan down into nine stages.
Each of those stages corresponds
to the individual length and bearing of a hole
from an iconic golf course.
Forget Whistling Straits, Augusta, or the Ocean Course.
This will be the toughest round of golf anyone has ever played.
On April 10th, Hambleton's radio
crackles to life.
The voice on the other end belongs to
Air Force Captain Harold Ike.
Hambleton's life depends
on him being able to decode what he hears next.
Ike tells him,
you're going to play nine holes,
and you're going to get in the Suwannee.
The round starts at number one at Tucson National.
Now, at first, Hambleton's totally confused
as would be any of the North Vietnamese
that are listening in.
But then Hambleton realizes that message
is so strange, it must be a code.
The Suwannee is a river in the U.S.,
So he figures they must be giving him coded directions
to get to a nearby river.
Hambleton racks his brains
trying to remember everything he can
about the course at Tucson.
The first hole is 430 yards running southeast.
Suddenly, he realizes that's his first direction.
Hambleton can hear enemy activity all around,
so he waits until the cover of nightfall before teeing off.
As he starts moving, it's tough going for Hambleton.
He has to count his strides, moving through darkness,
navigating through potential minefields,
and avoiding enemy soldiers.
After 40 minutes, he makes it to the first hole.
That's one hole down. Eight more to go.
He makes it through four holes
before dawn breaks when he takes cover again.
Next evening, he moves on to hole 5,
and this one comes with a serious hazard.
The fifth hole is the number four
at Abilene Country Club, where Hambleton
once hit a hole in one.
This time it's not so easy.
The route takes him right through the outskirts
of a Vietnamese village.
As he's tiptoeing through this village,
suddenly, from around a building,
a man leaps out at him brandishing a blade.
Instinct takes over, and Hambleton
pulls out his own knife, plunging it into his attacker
before escaping onward into the jungle.
Now his next round is against the clock,
because once the body is discovered,
the North Vietnamese will be hot on his trail.
Over the final four holes,
Hambleton grows weaker and weaker.
After three days,
Hambleton makes it to the ninth and final hole.
He locates his extraction point and waits.
It feels like his ordeal is nearly over.
Then Hambleton's heart sinks.
He spots a sampan boat heading upriver
towards him, with a Vietnamese man on the prowl,
holding an AK-47.
Days of surviving in the jungle,
only to get caught now.
But then someone else emerges from the boat.
It's an American.
It's the Navy SEAL extraction team.
News of Hambleton's rescue
hits the headlines, but something crucial is missing.
All mention of the Navy's clever code
has been scrubbed from the stories.
The secret remains locked away for nearly a decade,
until 1980, when Hambleton finally reveals
the story of his amazing escape
and the world hears of one of the U.S. military's
most audacious codes.
Improvising a code to rescue a man
behind enemy lines is one thing.
But during World War II, the U.S. military
needs something that can save thousands
and help turn the tide of the war.
So they turned to an unlikely source,
an ancient Native American language.
After months of Naval warfare,
the U.S. military is prepping to engage the Japanese
on land for the first time,
and their plan is to island hop their way
across the Pacific towards the Japanese mainland.
Radio communication will play
a pivotal role in the campaign,
but it has a downside.
In the chaos of battle,
there is no quick way to encrypt
or decrypt battlefield commands.
So Japanese forces will be able to hear
everything the U.S. is saying.
In 1942, an engineer
raised in a remote region of Arizona
has an idea which could change all that.
His name is Philip Johnston.
Philip Johnston was
actually raised by missionaries on a Navajo reservation.
And as such, he learned the Navajo language.
Johnston recommends to the U.S. Army
using Navajo speakers as code talkers,
communicating battlefield orders in real time
before the Japanese can decipher them.
It's estimated that less than 30 non-Navajo
speak the language in 1942,
making the odds of a Japanese soldier
being able to understand Navajo virtually zero.
When the U.S. military hears
about Johnston's idea, they take notice.
He's asked to come in and put his idea to the test.
In February 1942, Johnston assembles
four Navajo men at Camp Elliott in San Diego.
Under the scrutiny of the top brass,
the Navajo sit in separate offices
and are made to relay half a dozen simple messages
to each other via telephone.
The Navajo test subjects perform flawlessly.
The messages are relayed far faster
than they could have been encoded and decoded,
and there's not a single mistake among them.
Johnston's big idea gets the green light.
Now he needs to scale it up for battle.
Hundreds of Navajo volunteer for service,
and they're rapidly given basic military training.
But pretty soon, a problem arises.
The Navajo language is almost a thousand years old,
but this language doesn't contain
any words for modern warfare.
To get around the missing words,
Johnston proposes using everyday words
that have military meanings.
So for example, "whale" became the word
that was used for battleships.
In November 1942,
the first 13 Navajo code talkers
are deployed to the Pacific.
It's finally time to put Johnston's idea
to the ultimate test in the heat of battle.
Chester Nez and Roy Begay
are two of the first Navajo code talkers
who arrive in Guadalcanal.
And they have a literal trial by fire.
On the 7th of November,
Chester and Roy's platoon comes under attack
as they try to take an airfield.
They are pinned down.
A runner comes with an urgent message
to call in an artillery strike.
While bullets and mortar rounds whiz overhead,
Chester begins transmitting the message
to call in the artillery strike
in his native language of Navajo.
Seconds later, artillery buzz overhead,
neutralizing the Japanese machine gun nest
holding them down.
The entire message
took just 20 seconds to send and receive.
If sent using standard military code,
it would have taken 30 minutes,
by which time Roy and Chester's company
would have been annihilated.
Roy and Chester's commanding general contacts his superiors,
saying this Navajo code is terrific.
The enemy never understood it.
We don't understand it either, but it works.
Send us more Navajos.
After the arrival of the Navajo code talkers,
the American forces go on to win
the Battle of Guadalcanal.
It's a decisive point in the fighting
in the Southwest Pacific.
The Navajo code talkers
continued to play a critical role,
including in pivotal action at Iwo Jima and Bougainville.
And the Japanese never managed to figure out
their ancient language.
After the war is over, code talkers
don't get the official recognition they deserve.
While part of that is due to race relations at the time,
a larger part is due to the oath
that the code talkers took,
promising to keep their operations secret
in case they were ever called upon in time of need again.
Only in 1968 is
the service record of the code talkers declassified.
Then, in 2008, President George W. Bush
signs the Code Talkers Recognition Act,
and the hidden heroes of the Pacific War
are finally given their due.
After Pearl Harbor, a U.S. codebreaker
discovers Japan is planning an even more devastating attack,
only he doesn't know where.
If he can't crack the Japanese cipher,
then the whole U.S. Pacific Fleet could be destroyed.
On December 7, 1941,
the Japanese launch a surprise attack
on the U.S. fleet at Pearl Harbor,
claiming the lives of over 2,400 Americans.
Pearl Harbor ranks with 9/11 as the worst
intelligence failure in American history.
Captain Joseph Rochefort
is the head of the codebreaking unit
at Pearl Harbor.
Rochefort vows to make sure the U.S. will never
be ambushed like this again.
In the aftermath of the attack,
Rochefort and his team are tasked
with cracking the notorious Japanese code JN-25.
The code uses a huge codebook to translate
common words and phrases into individual five-digit numbers.
From there, there's
an additive codebook that then scrambles
those numbers yet again.
This dual system makes it just about impossible to break.
Rochefort and his team
began studying the mass of Japanese communications
from the days leading up to Pearl Harbor.
Rochefort discovers that, in the rush before Pearl Harbor,
the Japanese coders got careless.
They began transmitting codes using
an additive book that had already been
partially cracked by the U.S.
This allows Rochefort to spot something else.
It seems that when the Japanese are discussing
target locations, they use the prefix A
to represent U.S. interests in the Pacific.
AI seems to stand for Oahu.
AH is Hawaii; AK, Pearl Harbor.
Soon after Rochefort has discovered these
two-letter codes, a fresh set of intercepts
arrive mentioning a fourth two-letter code location.
Japanese air commanders are inquiring about wind speed
for an upcoming attack on AF.
What the Americans don't want is to be caught
in some kind of trap.
It's so very important to know exactly where AF is.
Rochefort is reading
the messages over and over, and then it hits him.
He looks at who the message was sent to
and who it wasn't sent to.
And Rochefort notices that there was
one military branch that didn't receive the message,
submarine commanders.
If submarines are not included,
this attack is likely to be an air attack,
meaning AF needs to be within range of the Japanese base
on the Marshall Islands, where their
aircraft carriers are harbored.
That narrows down AF to only a few possible locations.
By process of elimination,
he knows the attack can't be on the Hawaiian Islands
because they have a code name assigned to them.
And so, narrowing it down,
he knows that AF has to indicate
the American bases on Midway.
Rochefort believes he's cracked the code
and knows where the attack will happen.
But it all counts for nothing if he
can't convince his commanders.
The stakes couldn't be higher.
It's crucial that the Americans
hold on to Midway.
After the losses already suffered at Pearl Harbor,
to lose Midway at this point would kind of be like
the 1-2 punch that really makes the knockout.
Rochefort has this sense that AF is Midway,
but he can't prove it.
And there's no way that he is going to advise Admiral Nimitz,
who commanded the Pacific Fleet,
to send out America's remaining carriers
to ambush the Japanese on that kind of hunch.
So he comes up with a plan.
Rochefort arranges for
Midway's garrison commander to send a fake message,
saying that they're low on fresh water.
Now, if the message is sent uncoded,
the Japanese will immediately realize it's fake.
So Rochefort gets the message sent
using a U.S. cipher that he knows the Japanese
have already cracked.
Then Rochefort waits.
48 hours later, he gets the response he was banking on.
Rochefort's team decodes a message
about the imminent attack on AF,
and it specifically states AF is low on water.
This is the clincher Admiral Nimitz needs.
AF is Midway.
This is the kind of intelligence
that commanders dream of.
Nimitz understood that, if he got it right,
the Japanese Pacific fleet would be devastated.
Somebody was headed for an ambush.
Would it be the Americans or the Japanese?
Wasting no time,
Admiral Nimitz sends three aircraft carriers
with 117 aircraft to await the Japanese.
On June the 4th, 1942,
they catch the Japanese fleet entirely by surprise.
The Battle of Midway is resounding naval victory
for the United States.
The United States sends to the bottom of the Pacific
four Japanese aircraft carriers,
thus neutralizing the Japanese threat in the Pacific.
Midway is such an incredible triumph
that everyone wants a piece of the glory.
And credit for cracking JN-25 is
ultimately claimed by the Director of Naval Intelligence.
And Rochefort's role is basically
forgotten from history.
Only in 1985, when a book is published
by a former colleague, is Rochefort finally
revealed as the unsung hero
who stopped a second Pearl Harbor.
The following year, he is posthumously awarded
the Navy Distinguished Service Medal.
When a U.S. POW in North Vietnam's
Hanoi Hilton wants to reveal to the world
that he's being tortured,
he does it without his captors noticing.
Blink, and you'll miss it.
Commander Jeremiah Denton
is an experienced and respected career aviator
in the U.S. Navy.
In 1965, he's flying a bombing mission
when his airplane is struck by anti-aircraft fire.
Denton manages to bail out and parachute to safety,
but he's quickly captured by Vietnamese forces
who take him to the infamous prison Hoa Lo.
The prison is better known among U.S. POWs
by its nickname, the Hanoi Hilton.
But there's nothing luxurious about the conditions
Denton checks into.
Hoa Lo is a horrid situation for the aviators
that are held there.
The Vietnamese classify American aviators
as air pirates, and they claim that they are not protected
by the Geneva Convention.
They are kept in a prison facility
where they're often subjected to harsh interrogation
and torture.
They're not allowed to communicate
with one another,
and any attempt to speak to a fellow prisoner
will probably result in a pretty nasty beating.
Denton understands keeping his sanity
intact relies on one thing.
He must find a way to connect with his fellow inmates.
Denton discovers that the POWs
have already found a way to communicate
without using spoken words.
They pass messages by tapping on their cell walls
in Morse code.
Through their secret communications,
Denton is able to incite a campaign of resistance.
But the guards identify Denton as the ringleader.
He is beaten and brutally tortured.
In October 1967,
Denton is moved to another prison unit
reserved for the inmates deemed to be troublemakers.
This one has the less ironic nickname, Alcatraz.
Here, the tap code won't work.
Alcatraz is a much harsher system,
and the guards will inflict punishment
on any individual who appears to be
communicating via Morse code or any other form
of encryption system.
Denton is desperate to communicate
with any of the other POWs there,
but he's terrified of any more torture.
So Denton starts devising an entirely
new code based on the sounds he hears all around him,
and that the guards would never think twice about--
coughs and sniffs.
Due to the terrible conditions,
practically all the inmates
have some sort of respiratory problem.
So coughs and sniffs will easily
fall under the cover of the current
environmental conditions.
With this new code, a single cough means one,
a cough or a sniff twice means two,
and so forth and so on.
Using a standard five by five grid,
where each letter is designated two numbers
between one and five,
the airmen are able to spell out full messages
to each other without anyone ever detecting it.
Denton wants to speak to more
than his fellow prisoners.
What he dreams of is to be able to tell
the outside world of the brutal conditions
being endured by POWs.
One time out of the blue,
Denton got an incredible opportunity.
After nearly 10 months of captivity,
the guards informed Denton that the following day
he is to be interviewed in front of a global audience.
Denton is told that this
media appearance is very important,
and he is warned to be on his best behavior.
It's entirely likely that, if he doesn't comply,
he'll be killed.
How can he tell the world what's happening
without his captors finding out?
Denton's solution is ingenious and so sensitive,
it remains secret for years to come.
Morning comes, and Denton
is taken out of his cell, blindfolded,
and driven away from the prison.
He finds himself in a nicely-appointed room,
sitting in front of a Japanese journalist and crew.
Denton has no idea how
he can subvert this interview.
But then it's action.
The lights go on, and he's temporarily blinded,
and he squints and blinks to try to avert
the light from his eyes.
And then the idea comes to him.
Denton is answering the questions
in the way that his captors want him to.
But his eyes are telling a completely different story.
Denton's blinking is actually spelling out
a message in Morse code.
The message spells out one word, "torture."
In plain sight, with the world watching,
Denton spells out "torture" in Morse code again and again,
a single word that says it all.
The North Vietnamese don't notice what Denton is up to,
and the broadcast is actually transmitted worldwide.
This is big news.
It's the first indication that
the United States has that North Vietnam
is violating the Geneva Convention.
Denton has no idea
if his message has been heard.
The U.S. authorities never make public
his blink code, fearful that it would lead
to more extreme consequences,
like more beatings or even execution.
He doesn't find out that his code
was actually received until 1973
when he's finally released.
A year later, Denton is awarded
the Navy Cross for his conduct during captivity.
But the full story of his ordeal
remains unknown until 1975,
when he publishes his memoir, "When Hell Was In Session."
And now the world finally discovers the story
of Denton's courageous blinking code.
What if I told you that a key part of beating
the Nazi's unbreakable Enigma code
was a bunch of Ohio factory workers
who made cash registers?
It's a wartime secret so sensitive
that it remains under wraps for more than 50 years.
In the early 1940s,
it's open season in the North Atlantic
for Nazi submarine wolfpacks.
The German Navy is sinking vast numbers of Allied ships.
From the summer of 1940
into the spring of 1941, hundreds of allied ships
are sent to the bottom of the Atlantic by German U-boats.
It's what the U-boat crews gloatingly call the happy time.
The secret weapon behind all this
is the Enigma device, a code machine the Nazis used
to encrypt orders to their submarine fleet.
If the Allies are to escape the U-boat attacks,
this code needs breaking.
But that's no easy task.
The Enigma machine is a typewriter-like device
that's used to encrypt messages and then unencrypt them
so they can be read normally.
For the process to work, both the sending and receiving
Enigma machines have three rotors
that have to be set to the same configurations.
And those are determined by using the key from a code book.
Unless you had the code book
and the setting sheets,
it is impossible to solve this by simple trial and error.
Then, in 1941, the British
have a major stroke of luck.
Their Navy captures an enemy U-boat
with an intact Enigma machine plus codebooks.
Now they are able to use their own decryption device,
which they call the bombe.
Overnight, they can now listen to encrypted
German communications. U-boat patrols are tracked.
Thousands of lives are saved.
But nine months later,
the German Navy decides to ramp up their security.
In February of 1942, the Germans quietly
roll out a new version of the Enigma machine
that has now a new fourth rotor.
Adding that single extra dial results in the number
of extra settings possible for encrypting the codes
increasing exponentially.
There are now 92 septillion different ways
to set up a German 4-rotor Naval Enigma machine.
It's a complete disaster for the Allies,
and they are completely locked out
of German Naval-encrypted communications.
U-boats basically go on the rampage again.
The British need a much faster
version of the bombe.
And that means not having to design
a mechanical decryption device,
but an electronic one.
The British are struggling to produce these machines,
so they turn to the United States,
and they ask for assistance.
Washington starts looking for someone
to build this new, improved bombe.
They need a visionary engineer with a team
of electronics experts in a vast manufacturing space.
They find all three in Dayton, Ohio,
at the National Cash Register Company,
or NCR.
The NCR is a world leader in electronics,
and they just invented the world's first
electronic accounting machine
that runs at a million pulses per second, a megahertz.
NCR has an enormous
production facility in Dayton.
They're led by Joseph Desch, an engineer
who has an intrinsic grasp of the potential of electronics.
Desch designs a way
of scaling up the British bombe,
utilizing the might of American engineering.
The biggest issue is it comes with an incredible price tag,
around $4 million each.
It also weighs over 2 and 1/2 tons.
So it needs to be built in a special room of the NCR
with one of the first steel-reinforced
concrete floors in the United States.
The Navy signs off on the costs,
and Desch's team gets building.
The process is relentless,
with the team working seven days a week.
Finally, on May 28, 1943,
after 11 long months, Desch's super sized bombe
gets its first test.
Inside the NCR,
Desch switches on the machine.
And he feeds it an Enigma M4 message.
The machine starts up.
It begins to whine.
And then the machine stops.
It seems like an electrical short circuit,
and the teams are deflated.
But suddenly it springs back to life.
And incredibly the machine scores a hit.
It prints out the precise key used to encipher the message.
They then use that key to set the rotors
on their own Enigma machine.
They can then decipher the code and reveal
the original message.
Desch has done it.
He sends the results direct
to the codebreakers in Washington.
Soon, Desch's machines
are being put to work decrypting German messages.
The Americans and the British are actually
decrypting Enigma messages faster
than the German recipients are.
After NCR and its decryption machines
start going into action,
the tide turns against the German U-boat commanders.
It stops being a happy time,
and it starts becoming a Nazi-hunting time.
For over 50 years,
the Dayton codebreakers' contribution
to breaking Enigma remains classified.
Desch and the women who made the U.S. bombe
take their secrets to the grave.
Only in 1995, after a campaign by Desch's daughter,
is their role finally acknowledged.
It's 1968.
Someone is selling the U.S. Navy's
top secrets to the Soviets,
and the Navy brass have no idea it's even happening.
When the truth is finally revealed after two decades,
it's not by the FBI or the CIA.
It's by a disgruntled spouse.
Senior U.S. Naval officials are a bit troubled.
Time and again, their opponents seem to gain the upper hand
on them and anticipate their moves
with almost clairvoyant skill.
From tracking their subs in the Atlantic
to eventually dodging bombing raids in Vietnam,
they sense that something is up.
The U.S. has no idea how this is happening.
It's as if the USSR has cracked U.S. Naval codes.
To U.S. commanders, that's a ludicrous suggestion.
At this time, the U.S. Navy uses
one of the world's most advanced coding machines,
known as the KW7.
It is one of the first fully electronic coding machines,
faster and more secure than ever before.
In order to break this code,
the enemy would have to get their hands on a KW7 machine
and have access to the key cards
that are necessary to operate it.
Those key cards, however, are changed out regularly,
usually about once a month.
And that means that even if the Soviets get their hands
on a machine, well, they'd still have
to have the latest key card in order
to figure out what a coded message says.
The Soviets have got their hands on some KW7s
after a U.S. ship was captured in North Korea.
But because the captured machines didn't have key cards
with them, the U.S. Navy believed that their code
was still secure.
A series of security breaches followed,
but the Navy is sure that this is just a run of bad luck.
It's not just bad luck.
It's something far worse.
Their top secret code is no longer secret.
The truth is first discovered
not by a cryptography specialist,
but by a housewife in Virginia.
Barbara Walker is the wife of John Walker,
a radioman in the U.S. Navy.
From the outside, they have a happy life with four kids.
They'd had money troubles before,
but now they live a very comfortable life,
a fact she puts down to John's rising career.
One day, Barbara Walker comes across something strange.
Tucked away in a closet is a grocery bag
stuffed with classified Navy documents.
And they've been hidden away there by John.
When confronted, Walker comes clean.
He's been stealing top secret information
and passing it to the Soviets in exchange
for millions of dollars.
Among John Walker's responsibilities
is taking care of these KW7 seven cards.
It's his duty and responsibility
to destroy the old ones and to safeguard the new ones.
But instead of doing that,
he's sending them to the Soviets.
Once they have the keycards,
the Soviets can decode the American messages
that they recorded over the previous month.
The Soviets then tunnel
their way into at least a million
encrypted Naval messages.
It's the most damaging
code breach in U.S. history,
and the Americans don't even know it's happening.
For over ten years,
John is able to intimidate Barbara
into keeping his secret.
Barbara is terrified of her husband's temper.
And she fears that, if she goes to the authorities,
she might lose her kids.
Over the years, John secretly drags more family members
into his twisted spy world, including
one of their adult sons.
Then in 1984, Barbara finally
breaks John's hold over her.
Barbara learns that John recently attempted
to pull their daughter in.
Even though the daughter refused,
she picks up the phone and calls the FBI.
She tells them about the drops,
what he's doing, how this all works.
As they listen, they see the KGB patterns at play.
Furthermore, as they investigate Walker,
it becomes clear that he has a little more cash
than one should for his station.
And he's taking some rather odd trips at odd times.
But they need more than
just circumstantial evidence.
So they attempt to catch John in the act.
In May 1985, the FBI trails Walker
to a wooded area near Washington, DC,
and watches him hide a package before leaving,
a classic dead drop.
Agents move in and retrieve the documents.
It's a goldmine.
Inside, they find 129 pages of classified material.
John is arrested at his hotel room just a few hours later.
Faced with the prospect of life in prison,
Walker does the only thing he can.
He makes a deal.
In exchange for his full confession,
he negotiates a more lenient sentence for his son, Michael.
John Walker is sentenced to life in prison.
For the Russians, this has been
a brilliantly simple strategy.
Their code breakers haven't had to crack anything.
All they had to do was crack open the checkbook.
The story explodes across the media,
along with Walker's stinging comment
that Kmart has better security than the Navy.
When the story of this domestic spy ring
goes public, it reveals huge flaws
in U.S. Naval security,
leading to the implementation of new security measures
to ensure this won't happen again.
It's New York in 1919.
A poker prodigy is lying in bed.
He's about to doze off when he's
struck by a flash of inspiration,
one that will help him crack a notoriously
difficult Japanese code.
In the aftermath of World War I,
American leaders have learned a hard lesson.
Information is power.
So if you can read other nations codes,
you can know what your enemies and even your friends
are really thinking.
Even in peacetime,
Washington doesn't want to rely on what other governments
choose to tell them,
so they decide to start cracking
other countries' codes.
The U.S. turns to an unlikely establishment
that publishes puzzle books from a nondescript brownstone
in New York City.
It's the secret headquarters of the U.S.'s
most advanced code-breaking operation,
called the Cipher Bureau,
an outfit so secret that it doesn't
even officially exist--
essentially, a U.S. government black op.
The young man who runs this
is Herbert Yardley, a prodigy with a flair
for numbers and puzzles.
In fact, he funded his education
through poker winnings.
Working for the State Department,
he secretly cracked a coded message,
meant only for the president in just two hours.
From there, Yardley's skills land him his own gig,
running the secret codebreaking team for the U.S. government
under its cover as a puzzle publisher.
Yardley and his Cipher Bureau
break all kinds of codes for the U.S. government.
Around 20 countries have their messages
cracked by Yardley's outfit.
The Cipher Bureau's most fiendish challenge
is cracking Japanese coded telegrams.
These are concerned with Japanese and U.S. negotiations
over a Naval Arms Limitation Treaty.
Yardley's Cipher Bureau is given
a collection of diplomatic cables from Japan to decode.
And this is a monumental challenge
because, even before you consider any encryption,
Japanese is incredibly complicated.
Instead of a 26-letter alphabet
like we have in English, they have the kana,
which is a collection of every possible syllable sound,
and there are 73 of those.
Despite the scale of the challenge,
Yardley vows that if he doesn't break the code
within a year, he will resign.
But after half a year, Yardley still can't
discern any real patterns.
He's really starting to wish he hadn't been
so hasty offering to resign.
Yardley dedicates so much of his time to breaking the codes
that he even starts dreaming about them.
And one night, inspiration strikes.
Suddenly, he's able to pick out
the Japanese word for Ireland in the telegrams.
Irish independence is in the news right now,
and the Japanese are discussing it
in their diplomatic telegrams.
Now it's like he has the corner of a jigsaw puzzle,
and he builds out from this,
cracking one syllable and then another.
And finally, after six months,
Yardley and his team have the Japanese code
completely defeated.
Yardley's work helped
secure a historic peace deal on U.S. terms,
and Yardley is rewarded with a Distinguished Service Medal.
But this becomes the high point
of his code-breaking career.
By 1929, after a series of funding cuts,
Yardley's Cipher Bureau is closed for good.
But because it didn't officially exist,
he's not able to draw a civil service pension.
So in the end, he ends up broke.
Feeling betrayed,
Yardley decides to publish a tell-all book
called "The American Black Chamber."
This effectively makes him the Edward Snowden of his time,
but it also makes him a small fortune.
He rakes in the equivalent of half a million dollars
in today's currency.
The U.S. government is outraged by Yardley
having gone from their secret puzzle nerd
to a rogue operator.
Yardley's book is an embarrassment
to the U.S. government.
Because of it, some 19 nations are alerted
that their codes have been broken
by the United States.
They can't throw him in jail because only limited laws exist
on spilling state secrets.
In March of 1933,
Congress amends the Espionage Act
by passing an act for the protection
of government records.
This prohibits the disclosure of anything sent in code.
These laws Yardley inspired
become informally known as the Official Secrets Act,
and they still bind government officials today.
From a prison cell to battlefields,
secret codes are a vital way nations hide information
from their enemies.
But for every locked door, there is a key,
and for every code,
a genius mind trying to crack it.