Original subtitles

Poland, September 1st, 1939, just before dawn.

The streets are quiet, but that won't last

much longer.

The distant sound of air raid sirens heralds

a terrifying reality.

Germany is invading, and World War II

has just begun.

[intense music playing]

[Josh] In a lightning-fast assault known as the Blitzkrieg,

Nazi Germany paralyzes their enemies

through overwhelming force.

In Poland, the destruction is catastrophic,

with entire cities laid to waste.

Soon, more than a dozen other dominoes will fall.

Norway, Denmark, the Netherlands,

Belgium, France.

Standing in the way of Nazi domination

is Great Britain, but German U-boats threaten

to bring the island nation to her knees.

[loud explosion]

[Josh] Germany's submarines were the single

most feared weapons in the beginning of World War II,

using their stealth and up to 14 torpedoes each

to hunt in feared wolf packs and obliterate British vessels,

crippling their supply lines.

And the Nazis dream of making their subs even deadlier.

Enter German rocket engineer Hellmuth Walter

and a game-changing U-boat that could spell Nazi victory.

The top-secret V-80 is a one-of-a-kind prototype,

a revolutionary rocket-fueled vessel that reaches

unprecedented speeds and stays below the surface

longer than any other submarine.

If U-boats boasting V-80 technology are

launched in time, the United Kingdom will fall

with Nazi banners flying over London.

Thankfully, our epic invasion on D-Day spells

the beginning of the end for the Third Reich.

And as the victorious Allies liberate Europe, the Nazis hide

their cutting-edge technology by sinking the V-80,

sending this game-changing sub to the depths,

never to be seen again.

Eighty years later, the legendary V-80 is

still lost.

Now a team of Polish explorers is using modern

sonar technology and declassified World War II files

to lead an all-out hunt for the missing Nazi super-sub.

So damn the torpedoes and set a course for the icy waters

of the Baltic Sea on a daring mission to find

Hitler's secret submarine.

[theme music playing]

[Josh] The past is all around us.

Oh my God!

It goes on forever!

A world of mystery...

Come on! Look at that!

-Danger... -Hang on!

-...and adventure. -It's just straight down!

I gotta get a new job.

I travel to the far corners of the Earth to uncover

where legends end... -Yeah!

We got it! Yes!

...and history begins.

Whoo-hoo! Here we go.

I'm Josh Gates, and this is Expedition Unknown.

[epic music playing]

[Josh] My search for the V-80 begins in Germany,

in the coastal city of Bremerhaven.

Located at the mouth of the Weser River here

on the edge of the North Sea, Bremerhaven was a key base

for the German Navy or Kriegsmarine,

during World War II.

It served as a hub of U-boat operations,

producing and repairing subs that terrorized Allied ships

crossing the Atlantic.

The Battle of the Atlantic was World War II's longest

continuous military campaign, starting in 1939 and spanning

the entire duration of the war until victory in Europe

in 1945.

Under the leadership of Nazi arch-villain

Admiral Karl Dönitz, U-boats are ordered to hunt

Allied ships with abandon,

destroying them faster than they can be built.

He even instructs U-boats to not rescue survivors at sea.

The campaign brings Britain to the brink.

But German engineers like Hellmuth Walter

toil in the shadows to build an even more terrifying sub.

And he did.

Not far from this shoreline, Walter designed the V-80,

a lethal German U-boat that would change

submarines forever.

To get debriefed on the V-80 and how it nearly became

an unstoppable Nazi super weapon,

I'm meeting with historian Heiko Mross

aboard a real German U-boat,

the imposing Wilhelm Bauer.

-Heiko! -[Heiko] Josh!

-Hi. -[Heiko] Hello.

-Nice to meet you. -Yeah, how are you doing?

Oh, this is amazing. Look at this!

This is my first time standing on top of a U-boat.

This is an astounding piece of technology.

Any chance that this is the V-80?

This is not V-80.

Oh, I was gonna say, my mission would be be over,

it'd be so simple. -This is a submarine

Type 21 and the last Type 21 in the world.

This is the most advanced submarine of Second World War

from Germany, and it could not be possible without V-80.

U-boats were a huge part of World War II,

and I think a lot of people probably assume

that their primary targets were military ships,

but that's not the case. -That's not the case.

The primary target was merchant vessels.

[Josh] Merchant vessels are critical to supplying the island nation

of Great Britain and her citizens.

Nazi Admiral Dönitz's strategy, known as a tonnage war,

is simple enough.

Sink as many Allied supplies as possible

and starve Britain into surrender.

Every month during the war, U-boats send more

than half a million tons of food, raw materials

and military resources to the bottom of the Atlantic.

Germany had how many U-boats during the war?

-We had about 1,100 U-boats. -1,100.

And a lot more than the Allies, right?

It was three-to-one.

But the Germans are not resting on their laurels.

No, no.

And that brings us to Hellmuth Walter

and to the V-80.

So who is Walter?

[Heiko speaking]

[Josh] A cutting-edge German engineer and inventor, Walter developed

liquid-fueled engines that ran on hydrogen peroxide,

a powerful, albeit volatile, fuel source.

His designs powered the Messerschmitt Komet,

the first operational rocket-powered fighter

in history.

He applied this same technology to German U-boat development.

The V-80 submarine is a one of a kind, right?

[Heiko speaking]

[Josh] Previous submarines had a bulbous cigar shape,

but the V -0 is built like a shark,

with a streamlined hull that slices through the water

and a distinctive conning tower that would rise

above the surface like a dorsal fin.

-So how fast could the V-80 go? -The V-80 could go 28 knots.

20 knots, that's like 33 miles an hour -- that's fast.

And how fast did U-boats go before that?

Um, about 8 knots.

So this thing was almost four times as fast

as other U-boats. -Exactly.

[Josh] But its shape isn't the only game changer.

Previous U-boats operated mainly at the surface.

Once submerged, they had less than 100 miles of range

before they had to return topside to run diesel engines

in the fresh air and recharge their batteries.

And this is a problem, right?

Because when a sub comes to the surface,

it's very vulnerable.

Three out of every four dies?

-Yes, right. -Wow, that's insane.

To keep the sub out of Allied crosshairs,

Walter uses hydrogen peroxide

to create a closed-cycle turbine engine.

Burning diesel fuel requires oxygen.

But instead of returning to the surface to get it,

the decomposition of hydrogen peroxide

creates oxygen underwater, which means the sub can stay submerged

and undetected for far longer.

Wow. Terrifying.

-Does the V-80 ever see combat? -Not at all.

It was a prototype.

It was a very small prototype, about 72 feet long

with about a crew of four to five members.

-Want to take a look inside? -Inside the sub?

-Inside the sub. -Oh, I would love to.

-Yeah. -Please, lead on.

We descend into the heart of the Type 21 U-boat,

the Nazis' most advanced killing machine

inspired by the V-80.

♪♪

Wow.

[chuckles] OK, this is crazy.

Welcome aboard a German submarine,

but don't touch anything. -This dive button?

-[Heiko chuckles] No. -[Josh] No? OK.

So this is like an engineering marvel.

This was really the first modern submarine in the world.

Imagine if the innovations of the V-80 were

adopted earlier and subs like this made it

into the water sooner.

The war might have been very different.

It might have totally changed the war.

All right, show me around, will you?

[Heiko] Come on.

OK, watch your head, everybody.

Heiko shows off 1945's state of the art, from stem to stern.

It borrows the V-80 shape, but not its propulsion system.

So this couldn't go as fast or stay under as long

as its prototype forebear.

Yeah, Josh, we're here in the torpedo compartment.

Here are the torpedo tubes. We're in the front of the boat.

Incredible.

The design of this is just remarkable.

And this brings us back to the V-80, which inspired

so much of this. -Yeah.

How significant would it be to find the V-80?

The V-80 is a missing link in the evolution

of the modern submarines. Finding it would be huge.

So the big question, where is the V-80?

I don't know. Nobody knows.

It's a mystery.

So this is today part of Poland, this area?

-Yes, that's right. -[Josh] OK.

And do we know why it disappeared?

[Josh] Only a few days before Germany's surrender,

on May 8, 1945, with Soviet forces closing in

on Berlin, Admiral Dönitz launches Operation Rainbow.

U-boat crews are instructed to scuttle, or sink,

their own subs to keep their cutting-edge technology

from falling into enemy hands.

And we think this is what happened with V-80

in the Baltic Sea.

Well, if I'm gonna find V-80, I need to go

to where she sank. So off to Poland.

-Off to Poland. -Thank you so much.

Good luck.

Roughly 400 miles east of Bremerhaven is

Gdansk, Poland, a vibrant port town

with a complicated history.

In 1939, Gdansk was the free city of Danzig,

a politically autonomous region created

by the Treaty of Versailles after World War I.

Governed by the League of Nations,

the city's population was primarily German, so Hitler made

recapturing Danzig a pretext for invading Poland.

Chasing down Nazi submarines means peeling back the layers

of history, like at this derelict factory,

which looks like a film set from a dystopian thriller.

At the height of World War II, this place churned out fleets

of deadly U-boats.

But 80 years later, it now serves a different purpose.

♪♪

Welcome to Food Hall Montownia, where the only submarines

you'll find today are sandwiches.

These industrial cranes once serviced the Nazi U-boat fleet.

Today, we'll need them to carry me out of here.

Basically, it's Hitler's worst nightmare,

a multicultural melting pot with dozens of restaurants

and bars featuring cuisine from all over the world.

If the Nazis had prevailed, I doubt I'd be eating

an American cheeseburger, Mexican nachos,

or a Greek gyro.

So eat your heart out, Adolf, and here's to the heroes

that won the war.

Following in the trail of the V-80,

I grabbed some wheels and head 20 miles up the coast.

It's just above freezing, and all around me are

the equally frigid waters of the Baltic Sea,

famous for its harsh and turbulent winter conditions.

So when the Nazis took Poland, they turned this part

of the Baltic Sea into an experimental test site

for the Navy.

It's where many ships were developed and repaired,

including U-boats.

After setting its blistering 33-mile-per-hour speed record,

V-80 was stationed here for further testing,

and the explorer I'm meeting believes it was scuttled nearby.

At a marina on Europe's longest wooden pier,

Jacek Dzienisiuk is ready to embark on a mission

to locate the legendary U-boat.

Josh.

-Nice to meet you. -Nice to meet you, too.

-OK, so, the Baltic Sea. -Exactly.

Now, my understanding is we have a lot of shipwrecks

out here? -Yeah, there are thousands.

Thousands known and thousands unknown.

-[Josh] Thousands of them? -Thousands of them.

The Baltic's graveyard is full of merchant and military ships

intended to supply Britain to the West

and their Soviet allies who were fighting the Germans

to the East.

And there's one unknown that I know we're both

very interested in, V-80. -Exactly.

Safe to say that somewhere out there is V-80?

-Yeah, that's correct. -She's here.

Absolutely.

You think you've got something?

Yeah, recently I located a target that looks promising.

You think it could be V-80?

Yeah, the size of it just looks right.

[Josh] On a recent scanning mission, Jacek flagged several

uncharted anomalies on his boat's sonar.

But before he could record precise coordinates

and take a closer pass, he was driven off the water

by the Baltic Sea's notoriously stormy and dangerous weather.

-And have you dived on it? -[Jacek] Not yet.

I have to wait for the right weather.

-And recently, it was very bad. -OK.

Doesn't look so bad now.

[Jacek] Yeah, that's correct, but it can change in a minute.

-And the water is very cold. -Uh-huh.

-It looks cold. -But if you you dare...

-To find V-80? -Yeah.

-[Josh] I dare. -[chuckles] Well, let's go then.

Come on.

We load onto the boat and head out to sea,

accompanied by Jacek's research partner,

military historian Zbigniew Okuniewski.

The water beneath us is literally freezing,

and somewhere ahead is a sunken sub with missing Nazi tech

that almost altered the fate of the world.

We motor a few miles off the coast, and then I spot

something ominous on the horizon.

What is that?

This is a Nazi secret torpedo testing facility

from Second World War.

Sorry, that's a secret Nazi torpedo base?

[epic music fades out]

[epic music playing]

Sorry, that's a secret Nazi torpedo base?

[Jacek] That's correct.

[Josh] I'm on the freezing waters of Poland's Gulf of Gdansk,

hunting a prototype submarine that nearly tipped the war

in Hitler's favor.

This part of the Baltic Sea was a Nazi stronghold

during World War II, and this crumbling structure

may be one reason why.

They were testing torpedoes.

They were launching them from the tubes underwater

and testing the explosives. -Unbelievable.

Wow.

Look at that, just a piece of history right there.

This is the Kriegsmarine's Submarine Arms Research Center.

Torpedoes were tested here, fired at various targets

across the bay.

Now, more than 80 years later, these ghostly and decaying ruins

are a clue, telling us we are in the zone

where the V-80 once patrolled.

Oh, so the U-boats would dock right in there?

[Jacek] That's correct.

It's like, explosives?

Explosives, weapons, parts of this building.

Uh, we have to slow down, you know, to be safe.

[Josh] That's no empty threat.

The curtain of mines and depth charges

that the Nazis used to protect these waters was impenetrable.

Even the vaunted Soviet Navy didn't attempt to venture here

until almost the end of the war.

Once we're clear of the tower, Jacek's research partner,

Zbigniew, joins us on deck.

Our vessel is equipped with sonar, which emits

acoustic pulses that echo back from the ocean floor,

creating a picture of the seabed.

Jacek previously identified several anomalies

on the northern edge of the bay, but weather forced him

back to shore.

Now we need to relocate those hits by searching

in the same area.

Mowing the lawn, back and forth, back and forth.

[epic music playing]

[Josh] Finally, after a few passes,

-Josh, we've got something here. -Oh!

-Look at this! -Oh my word!

Can we zoom in on that?

-What the hell is that? -[Jacek] I look at this.

[Josh] Oh, it is sticking up off the bottom for sure.

Yeah, that look really promising.

Right? We can see something kind of elongated,

and look at that shape.

I mean, it does look like that, right?

-Yes. -And it has that teardrop

shape like the V-80.

Yes, exactly.

[Josh] So there's something sticking up in the center

of the structure too. -[Zbigniew] Yeah.

-Could be a conning tower. -Exactly.

-Could be. -[Josh] Could we be

looking at a submarine?

-That's right. That's right. -Could be one.

Even the size of it looks familiar.

That is a great target, so we've gotta

mark that for sure.

[Josh] Jacek's hot lead checks out.

Roughly 72 feet long with a tower-like structure

rising out of the center, it's a strong match

for the V-80.

And it's not the only wreck out here.

-Something there. -[Jacek] Yeah.

-Something there. -[Jacek] Yeah, we've got it.

[Josh] Whoa!

That is definitely a sunken vessel.

-And look at the shape. -[Josh] That's two targets now.

Which one do you think we should go for?

We can go for T1.

So let's start with this target one.

-T1. -[Jacek] Yeah.

[Josh] We have two sonar hits, one with a distinctly

submarine shape.

Now comes the hard part, actually diving

in the Baltic Sea, where the water temperature is

legitimately freezing.

So, we're going to need more than just wetsuits

or we'll die from hypothermia.

Little warm right now.

Everything feels good.

Everything's gonna be fine, right?

We start by donning thermal layers,

then we slip into a full thermal suit,

then into a full dry suit.

Outside of that are thick waterproof booties...

Das Boot.

It's a German submarine. Doesn't matter.

...a full face mask, then sealed, gasketed gloves

like you might find on an astronaut.

Once we're kitted up, and against my better judgment,

we splash down.

♪♪

[Josh speaking]

Whoa!

[Jacek speaking]

[Josh speaking]

While I'm losing feeling in my fingers, Zbigniew is

on the surface manning the radio.

[Josh speaking]

[Zbigniew speaking]

[Josh speaking]

The target sits at nearly 100 feet,

so our bottom time will be limited.

If we don't get eyes on this thing right away,

we may not find it at all.

[Josh and Jacek speaking]

We continue swimming just above the bottom

until something materializes out of the gloom.

[Jacek speaking]

[Josh speaking]

[Jacek speaking]

[Josh speaking]

[Jacek speaking]

[Josh speaking]

[Jacek speaking]

[Josh] This appears to be a merchant ship

with openings in the deck that lead to cargo holds.

[Josh and Jacek speaking]

[Josh] The hull is largely intact, but there are damaged areas,

which indicate it may have been sunk by enemy forces.

[Josh] Once topside, we try to stop shivering

and get our core temperature up while relocating

to the coordinates of the second target.

This hit also looks like some kind of vessel.

So before I have time to talk myself out of getting

back into this ice bath,

we hit the water to investigate.

Oh!

[Josh] The conditions have deteriorated,

and our already limited visibility

is even worse as we descend.

[Josh and Jacek speaking]

[dramatic music playing]

[Josh and Jacek speaking]

[Josh] We just found something big at the bottom

of the icy Baltic Sea, where the experimental

Nazi U-boat V-80 was scuttled by the retreating German Navy.

But with limited visibility, we can only see

portions of the wreck.

[Josh and Jacek speaking]

[Josh] We know that the V-80 was sunk on purpose

to keep the revolutionary Nazi tech

from falling into Allied hands.

But even if they blew it to bits, we still may be able

to find identifying features.

[Jacek and Josh speaking]

[Josh] During World War II, both Allied and Nazi forces

placed sea or naval mines around important harbors

like this one, creating a defensive barrier

to protect valuable resources.

In this case, perhaps assets like the V-80.

Carrying up to 1,000 pounds of explosives,

a direct hit from a mine can puncture steel-hulled ships

and turn a wooden vessel into matchsticks.

[Jacek and Josh speaking]

[Josh] In the war, hundreds of thousands of naval mines

were planted by minelayer ships.

It is impossible to know for sure, but it appears

that this minelayer had a terrible accident,

meeting its fate while deploying its own deadly payload.

[Josh] But then we see something that may offer

another lethal clue.

[Jacek and Josh speaking]

[Josh] The white material in front of me is trinitrotoluene,

otherwise known as TNT.

Designed for anti-submarine warfare and used by both

Allied and Axis powers.

Depth charges would strike their targets

with a deadly hydraulic shockwave.

[Josh] Underwater, 250 pounds of TNT has a blast radius

of up to 30 feet, with enough power to pierce

a submarine's plated hull. -It's still alive.

[Josh] While the two sonar targets turn out to be forgotten traces

of the war, we need to do more digging to home in

on the missing sub.

[Josh] We surface and motor towards shore.

It's not the first time I've been told to go to Hell,

but it may be the first time it was meant literally.

Spelled H-E-single hockey stick, this "fresh Hel" ["fresh hell"]

sits at the very tip of the peninsula.

The devilish name may come from a word in Old Polish

meaning "exposed," and sitting here at the edge of the world,

that feels accurate.

We drop Zbigniew at the dock and arrange to meet him

later at the military archives, where he believes

recently declassified documents could open up a new search zone.

Meanwhile, Jacek and I walk together through Hel.

It's colder than I expected.

Ha! I walked right into that one.

Hel froze over.

Counter to everything I was taught, Hel is lovely,

today anyway.

Now it's a charming seaside village.

At the start of World War II, this infernal moniker was

far more fitting.

The Battle of Hel was an epic clash.

While much of Poland fell quickly, the Hel Peninsula

resisted Nazi occupation for more than a month

in the bloody face of overwhelming assaults

from air, land, and sea.

Recognizing the strategic importance of the peninsula,

between 1939 and 1941, Nazi Germany fortified

this position less than a mile from the center of town.

Oh, wow.

This looks like a rebel base from Star Wars.

What was this?

Wow, a gun battery.

So there was a gun in the middle of this.

[Jacek] Yeah, a huge one. Biggest in Europe, actually

-The biggest gun in Europe. -Exactly.

[Josh] Known as the Adolf gun, the 66-foot-long barrel

could fire a 15-inch diameter, 2,200-pound armor

piercing shell a staggering 35 miles.

Wow.

Crazy.

Back in Poland's possession, this artillery battery is now

the Museum of Coastal Defense,

celebrating the country's naval history.

We're here because Zbigniew has discovered

top secret World War II communiques to dial in

our hunt for the V-80.

What have you uncovered?

-[speaking in Polish] -[translator] My English is limited,

so I will speak in Polish.

My research team found classified documents about V-80.

These are secret documents?

[translator] The information we have is about Walter himself.

So, Walter, who designed this cutting-edge sub,

the story is that he scuttles it to keep it

out of the hands of the Allies. So, what becomes of Walter?

[translator] Walter ends up in British hands.

He's captured.

[translator] This is from the Joint Intelligence Objective Agency.

It tells us what happened after Walter was in Allied custody.

[Josh] Once he was captured, the V-80 mastermind became

a high-value asset for Operation Paperclip.

After World War II, more than 1,600 top German scientists

and engineers were brought to the United States

and put to work on U.S. military projects

to advanced rocketry, aviation and nuclear research

during the Cold War.

This is after the war.

They now have Walter in the States,

and he's unhappy.

He wants to go back to Germany. Is that what's happened?

[translator] Yes.

And where is he in the United States?

-New Jersey. -Oh, New Jersey.

No wonder he wants to leave.

So, they write, "As you may recall

"from previous discussions, the British consider

"that Walter is in possession of information so critical

"as to make it imperative that he remain

in the United States or United Kingdom."

And so, does he ever disclose to them in any of his meetings

and interrogations what he did with the V-80?

[translator] No.

But in another interrogation by British intelligence,

someone else does. -Who?

Heinz Ulrich.

Heinz Ulrich?

Heinz Ulrich was a Nazi test engineer

and Walter's right hand man.

He served as a crew member on the V-80 during speed

and depth trials.

And what does Ulrich tell the interrogators?

[translator] That he scuttled it outside of Hel Harbor.

So this is huge, because we now have information

about where V-80 left from to be scuttled.

Ulrich, in his interrogation, indicated a military facility

just beyond the main town, where the U-boats once docked.

[translator] And we now know the exact harbor.

-Can you show me? -Yes, of course.

Let's go. Come on.

Can I get a "Hel, yeah?"

The location of the base where V-80 was docked

just before she was scuttled is an Adolf gun sized lead.

[Josh] The military harbor of Hel.

And where was V-80?

[Josh] This is what? What is this?

Oh, my God! That's V-80!

That's the submarine.

[epic music playing]

-That is V-80. -[Zbigniew] Exactly.

That's the submarine. So it was docked right here.

-Right here! -[Zbigniew] Yes.

[Josh] Oh, my word. That's incredible.

I'm in the surprisingly quaint town of Hel, Poland,

where explorers Jacek and Zbigniew are hunting

Hitler's top secret submarine, the legendary V-80.

This one-of-a-kind prototype was so ahead of its time,

it changed submarine warfare forever.

So when they went to sink this sub, they sailed

out of this harbor straight out here.

[Zbigniew] Yes.

The engineer, Ulrich, in his interrogation,

did he say how far out they went?

-He was back fast. -[Zbigniew speaking]

So they couldn't have gone very far.

-Exactly. -So, this gives us

a really defined search area.

[Jacek speaking]

[Josh] That submarine has to be right out there.

-Yes. -Must be.

-Back to sea? -We have to.

[chuckles] We have to. Come on, this is amazing.

Let's go.

♪♪

[Josh] Armed with a declassified intel drawing,

giving us a tight search zone, we follow in V-80's wake.

To prevent the prototype from falling into enemy hands,

engineer Heinz Ulrich scuttled it somewhere nearby,

planting explosives and sending the V-80

to the literal depths of Hel.

So we may be retracing the final path of V-80.

[Josh] Oh, they didn't just open the hatches

and let it fill with water. They blew a hole in it.

That's a great clue.

And that should have happened somewhere around here.

-Exactly. -[Josh] OK,

so we've got a new area to scan. Let's see if we get lucky.

We motor out just beyond Hel Harbor.

Based on Ulrich's interrogation, the V-80

should be closer to shore and to the east of where we found

the minelayer and merchant ship.

Jacek activates the sonar and pilots the boat in a series

of parallel and overlapping lanes.

Minutes turn into hours as we pass back and forth,

working our way out from the mouth of the harbor,

hoping to find a 70-foot-long sonar anomaly on the bottom.

[Jacek speaking]

[Josh] Bingo.

Really solid target. What is that?

[Jacek] I don't know what it is.

[Josh] It's cylindrical.

Right? Long shape, whatever it is.

Something's sticking up off of it, it looks like.

It's got that teardrop shape, which we know V-80 had.

That has to be a wreck.

[Jacek] Yeah, it's absolutely a wreck.

You can see it kind of tapers down here at the end,

so that's -- that's really good.

That wreck is not marked on the chart?

[Jacek] Definitely not. It's absolutely new.

-Nothing here on the map. -What am I looking at?

Well, you're looking at a mystery.

Yeah, a mystery. Should we solve that mystery?

-Yeah, let's do it. -Come on, let's see what it is.

We bundle up in dry suits to brave the icy Baltic.

Today's forecast is the same as yesterday.

Really [bleep] cold.

♪♪

The water temperature is in the 30s.

Diving without protective layers,

we would quickly freeze.

[Josh and Jacek speaking]

[Josh] The bottom is shallow.

Our target sits at just 30 feet.

What do you see? What do you see?

[Josh speaking]

[Josh speaking]

[Jacek and Josh speaking]

[Josh speaking]

[Jacek speaking]

[Josh speaking]

[Josh] It's not the missing U-boat,

but this plane is a major find.

An artifact from the war that hasn't seen the light of day

in 80 years.

We circle the debris, searching for clues

that will help tell us its story.

[Jacek speaking]

[Josh and Jacek speaking]

[Josh] We also notice black discoloration,

a clear mark of fire.

It seems our mystery plane may have gone down on a bombing run

before it was able to drop its deadly payload.

Was this a Polish plane defending its homeland,

a Nazi bomber attacking it,

or an Allied aircraft liberating it?

[Josh] With ammunition and gun at the ready,

it appears the airmen were trying to defend themselves

from enemy fire.

And as we expand our search, carefully fanning sand to see

more of the wreck, a shocking discovery reveals

the stark horror that is war.

[Josh] In submarine design, every component can become

a matter of life and death, including the toilet.

Nazi Captain Karl Adolf Schlitt learned this lesson

the hard way, when a simple trip to the head

sank his own submarine.

U-1206 was cruising at 200 feet, eight nautical miles

off the coast of Scotland when nature called

for Captain Schlitt.

Unfortunately, he opened the wrong valve on the U-boat's

deep-water high-pressure toilet,

flooding the battery compartment with seawater

and kicking off a chemical reaction

that filled the vessel with lethal chlorine gas.

When the U-boat surfaced to clear the air,

the British were waiting.

Instead of suffocating, the crew was captured

and the submarine got sent to the depths permanently.

Germany surrendered just a few weeks later.

Ironically, the embarrassing incident may have saved

the crew's lives.

[Josh and Jacek speaking]

[Josh] At the bottom of the Baltic Sea,

near a hotly contested battleground during the Second World War,

Jacek and I have discovered a plane wreck.

While it's not the revolutionary V-80 U-boat,

it is a significant find, and a tragic one.

This is a war grave, the hallowed resting place

of an unknown pilot and gunner.

[Jacek and Josh speaking]

[Josh] We continue to investigate the uncharted site,

looking for forensic evidence to help identify the plane

and tell the story of these lost soldiers.

[Josh] Our bottom time is limited, so we quickly grab our camera

and start capturing a photo mosaic.

[shutter clicking]

I take hundreds of images, documenting every square inch,

enough to create an exact 3D digital replica of the wreck

and highlight features not obvious to the naked eye.

Hopefully, it's enough data to help us identify the wreck.

[Josh] Whoo!

Incredible.

Just an entire aircraft down there.

Nobody knows that's there.

-[Jacek] Nobody. -Nobody.

And it looks like we have remains down there as well.

-OK. -[Josh] So, I mean,

this is not just a piece of lost history,

but there's a personal story here, too.

-[Josh] Missing in action, yes. -Yeah.

OK, what will happen now with this plane?

Yeah, it is a grave, a war grave.

That's right. Amazing job.

Really amazing. Hey, great job.

Thank you so much.

V-80 is still out there, but this is a lost piece

of history that's lost no more.

[Josh] The photos come together like pieces in a puzzle.

The three-bladed propeller, distinct squared-off cockpit,

and tell-tale Berezin UBT machine gun

identify this plane as the Russian

ground attack aircraft Ilyushin Il-2,

known as the flying tank

for its heavily armored construction.

The Il-2 was so important to the Soviets during the war

that Stalin said, "It was as essential to the Red Army

as air and bread."

The crew of this plane made the ultimate sacrifice,

meeting their fate while liberating Poland

from the Nazis.

The Baltic doesn't give up its secrets easily,

but this mission was a major win

as we uncovered lost and important relics from the war.

A missing merchant vessel, a wrecked minelayer...

[Josh] ...and this historic discovery of an Il-2 aircraft.

[Josh] The V-80 remains unaccounted for,

but her legacy is clear.

She was a hallmark of naval engineering

and the first incarnation of modern submarines,

which influenced every sub built after.

But if the technological advances born

in Hellmuth Walter's revolutionary U-boat

had evolved slightly quicker,

a cascade of dominoes might have fallen.

Cut off from supplies, Britain may have starved,

and the flow of shipments that the Russian army relied upon

likely would have ceased, buying just enough time

for the Nazis to develop atomic weapons.

It's a haunting shadow of an alternative reality,

where freedom, liberty, and equality became

words that could only be whispered in secrecy.

We take for granted how close we came,

and too often forget the enormous sacrifices it took

to avoid that terrible fate.