Original subtitles

(mysterious music)

The tropical waters of Southeast Asia

are home to some of the richest coral reefs on the planet.

But hundreds of meters beneath the surface

lies a world where time had stood still.

(mysterious music)

Here, creatures from the far distant past still survive.

Now a team with scientists and film makers

have joint forces to explore this largely unknown world.

(indistinct radio talking)

With the state-of-the-art submersible,

they descend deep below the surface.

This is truly a living fossil here.

And discover prehistoric creatures

that have survived virtually unchanged

for over 400 million years.

(mysterious music)

It's a lost world hidden in the depths of the sea

where primeval creatures have lived

since the earliest times.

(mysterious music)

Following the reports from local fishermen,

the team set off in search of a strange fish

that is said to lurk in these waters.

Have you ever seen that fish before?

I caught one.

(majestic music)

It's a journey full of surprises

and extraordinarily encounters.

And finally, after a year of exploration.

Oh shit, this is what, this could be it.

This is it mate.

Yeah? Yeah.

We got them.

(laughter)

They discover a bizarre fish

that few people had ever seen,

and encounter some of the ocean's

most elusive inhabitants.

(indistinct talking)

This is gonna be awesome.

(exclaiming)

It's the journey of a lifetime.

(dramatic music)

(drums rolling)

(chanting in foreign language)

The island of New Guinea in the Pacific Ocean,

it's a wild paradise that still remains

largely untouched by modern civilization.

A scientific research vessel is here

to explore the uncharted depths of these waters.

The Alucia is equipped with the latest technology

including a deep sea submersible

that can dive to depths of 1,000 meters.

The crew are carrying out final safety checks

to the submersible Nadir.

No one before has attempted to dive

in these waters with a sub.

The expedition is led by marine biologist, Mark Ardmann.

Ardmann is an expert in the ecology of coral reefs

and has been studying them for over 20 years.

He's worked in these waters for over a decade

and knows them well.

Their first stop is the Raja Ampat Islands

of the west end of New Guinea.

(calm music)

Okay sir, ready?

Let's go.

The warm waters are teaming

with colorful fish.

Nowhere in all of seas of the world

is there a greater diversity of life.

(calm music)

Over 500 species of corals live here,

they in turn support a myriad of fish

that depend on them for food and shelter.

Tropical waters are surprisingly poor in nutrients,

but the corals produce enough food

to sustain a vast community of marine creatures.

Ardmann has identified over 1,500 species of fish

in the shallow waters here,

confirming that this is one of the greatest

biodiversity hot spots in the world.

But Ardmann has long been wanting

to explore the deeper ocean.

It all started with an extraordinary discovery

that he made over 15 years ago.

He was traveling around the island of Sulawesi,

in Indonesia.

So, it was on my honeymoon in 1997.

We were in Manado when we are doing some diving there,

and I always like to go to the fish market

just to see what the people are catching there.

So we went quite early in the morning.

My wife saw it first.

Very intrigued by what this was.

It was something she'd never seen before.

So she called me over and asked me what this was.

Ardmann immediaterly recognized

the bizarre looking fish.

And I said, oh my goodness, it's a coelacanth.

The coelacanth is a very rare fish

that was once thought to be the ancestor

of all land-living backbone animals.

It has armor-like scales and large bulging eyes,

and fleshy fins that resemble limbs.

Very surprised to see,

it's something I'd known as a child

but obviously never seen a real one,

so it was fantastic and a really big surprise to see.

Until the live specimen was caught

off the coast of South Africa in 1938,

the coelacanth was thought to be extinct.

It had only been known from fossils

over 80 million years old.

And the discovery of a living specimen

was a scientific sensation.

It was over a meter and a half long

and weighed nearly 60 kilos.

News of the strange primeval fish

soon spread around the world.

50 years later, Ardmann himself,

found another coelacanth in Asian waters

far from Africa.

It was a different species and once again

the strange fish captured our imagination.

(mysterious music)

Since then, a few more specimens

had been recovered in Indonesian waters

but only in a handful of places.

Ardmann believes that their range

maybe much wider than we think.

He's long had the dream of conducting

a full scale exploration of the deep Pacific Ocean.

Other prehistoric creatures such as deep-sea sharks

and nautilus, have already been discovered here

and he hopes one day to find the coelacanths too.

(majestic music)

There's an important question about

why we have so many of those here?

What about the deep tropical sea?

And perhaps really try to unlock some

of the mysteries of the deep tropical ancient seas here.

The expedition that Ardmann

and his colleagues are planning

will require much preparation

and take over a year.

From inside this submersible,

the team will have an unobstructed view,

nearly 360 degrees all around them.

The sub is also equipped with a high resolution camera

that can capture even softer shades of color underwater.

With final preparations complete,

the sub is ready for its descent.

I think that there's an extremely good chance

that coelacanths are found right here.

We're in the right place

and I'm extremely excited about this

and yeah, I'm just ready to go.

Ardmann is excited and nervous.

Guys happy?

Very Happy.

Ready to go.

(questing music)

The sub weighs nearly eight tons.

It will be lowered into the sea by a huge crane.

(questing music)

(engine roaring)

(questing music)

It's Ardmann's first dive into the deep

below the coral reef.

(indistinct talking)

Nearer to the surface, the swimmer clear,

am I clear to vent?

Oh, yeah, you're clear to vent.

Hey guys.

Here we go

All right.

Fingers crossed.

The sub slowly descends into the deep.

The lower they go, the darker it gets.

Very little light penetrates these gloomy depths.

[Man on the radio] Surface, surface Nadir,

depth now 34 meters on the wall, over.

Nadir, surface,

steady 34 meters on the wall, loud and clear.

Got a whole phalanx of little tiny squid.

directly in front of the lights.

[Man on the radio] Surface, surface, Nadir,

depth 170 meters.

The lights were okay.

Are we on the bottom?

Yeah.

The seafloor is very different

to the coral reef above.

Bare and barren, there is little sign of life here.

At last they spot something,

the strange heart-shape creature at the end of the stalk.

It's a rare comb jelly that was first discovered in 1941

by the Japanese Emperor, Hirohito,

who was also a passionate marine biologist.

This jelly-like creature lives attached to a rock

at the bottom of the sea

and feeds in the most extraordinary way.

It throws out long sticky filaments

which catch tiny prey drifting by in the water.

(mysterious music)

[Man on the radio] Surface, surface, Nadir, depth, 22--

The surface is now descended

to below 200 meters and is entering

what is known as the twilight zone.

Very little light penetrates as deeply as this.

That sea urchin is beautiful.

Oh that's--

The red one right there?

Yeah.

The sea urchin looks quite different

to most modern day urchins, having fewer spines.

In fact, it more close to resembles fossils

from 200 million years ago

and belongs to a primitive group known as the pencil urchins

because of the thickness of their spines.

The team notice another unusual creature on the seafloor.

This is truly a living fossil here,

if we can get up on that video

and I think this is one of the things that we rarely see.

So these are sea lilies which are now on stalks.

This is basically exactly what they look like

in a fossil record hundreds of millions of years ago.

Here we go.

There, and one up there.

(mumbles) over there.

The sea lily looks just like those

found as fossils dating back 400 million years.

It has ranged very little over millennia.

Perhaps sensing the sub's presence as it approaches,

the sea lily begins to wave its arms.

(mysterious music)

It may look like a plant but it is in fact an animal

and if in danger, it will resort to a remarkable strategy.

It detaches itself and uses its feathery arms

to crawl over the sea floor in search of a safe spot.

(mysterious music)

The sea lily may have retained its primitive form

for millions of years,

but it's also hardly enough to have survived

into the modern age.

Discovering these living fossils

has been quite overwhelming for Ardmann.

If we had a week of this--

Oh my God.

Stalked sea lilies like these were once

far more abundant than they are today

and then found mostly in shallow waters.

(bubbly music)

400 million years ago,

thick carpets of these strange creatures

covered the sea floor

forming spectacular underwater meadows.

The warm shallow waters were rich in plankton

and there were few large predators.

The nautilus, an ancient relative of the squid, octopus,

haunted small marine invertebrates such as trilobites.

Overtime, more former developed predators began to appear,

primitive sharks,

and huge armored fish.

With powerful jaws and the ability to swim swiftly,

these formidable hunters rule the shallow seas.

While many prehistoric creatures became extinct,

the sea lilies and some other species

survived as living fossils in the twilight zone.

The key to their success was their ability to adapt.

(calm music)

During the age of the dinosaurs,

even bigger and more ferocious predators appeared

in the shallow seas.

Large swimming reptiles like the plesiosaur.

(calm music)

Now, slow moving animals without weapons of their own,

made easy prey.

Those that lived in deep waters

were largely unaffected by this struggle to survival.

They are descendants of the living fossils

that we know today, the coelacanths and the sea lilies.

Here in the deep there were few competetors

and it was too dark from most predators to find them.

(calm music)

The sub has returned to the surface.

The first dive completed.

Thank you sir.

You're welcome.

It's a fantastic trip.

I would say it was other worldly,

it was truly a lost world that we encountered.

I think that if we had some more time here,

that we would definitely find coelacanths.

The team start planning

for their next phase of the expedition.

(lively music)

We gotta take a look here.

Ardmann decides to focus his search

on finding prehistoric fish including the coelacanth.

But where should he start to look?

Coelacanth are thought to be nocturnal,

hiding away in caves and rock crevices

around 200 meters below the surface.

There are hardly any maps of the seafloor

around New Guinea.

From the little information he has,

Ardmann decides to focus on a small island

called Wuvulu of the northern coast.

I think that Wuvulu looks to me

from the maps to be probably the steepest

and a few divers that I've spoken to talked about

very large caves there so that

could also be quite interesting.

So that's the general habitat that we're going to look for.

General topography is something

like quite steep and the caves.

If coelacanths do live in these waters,

Wuvulu could have the right kind of habitat.

(questing music)

They set course for this remote and little visit diver.

If we can confirm the existence of coelacanths here

in Northern PNG, it will be actually

a very significant scientific finding,

it will open the possibility that coelacanths

are found of course throughout this western pacific rim.

So we're very excited about this possibility.

30 hours later,

the ship has reached its destination

just north of New Guinea.

Wuvulu is about five kilometers long.

The team head towards the shore.

On the way, they encounter a fisherman in his small canoe.

He's just caught an oilfish nearly two meters long.

It's a deep sea fish usually found

at depths of around 500 meters.

(fisherman laughs)

Where did you catch this?

(foreign language)

This is the place for them.

It's definitely a good sign of good coelacanth habitat

which we already know from what we've seen in the sample.

It sounds like coelacanths and oilfish

maybe found in the same kind of habitat.

Ardmann and his team head towards the local village

to see if they can find out more.

The island has a population of some 900 people,

most of them making a living from fishing.

Everyone thinks they're a fish expert.

Have you caught any of this fishes before?

Yeah. Yeah?

Including this one?

Yes, but this one normally,

we use to catch this fish at night.

Right.

But what about the coelacanth?

This one is very rare.

Very rare, okay.

Ardmann then gets to meet a veteran fisherman

who gives him a crucial piece of information.

Let me ask you some questions.

Have you ever seen that fish before?

I caught one.

You caught one?

A small one.

A small one, yeah?

Did you catch that during the day or at night?

At night. At night, yeah?

And was it also in the same kind

of depths as this fish or, yeah?

About 200 to 300 meter deep.

Yeah?

Quite deep, yeah?

Okay.

Was that a long time ago or?

No, no.

Just recently?

This year.

This year, yeah?

Okay.

Ardmann asks the fisherman

to take them to the spot where he caught the coelacanth.

The Wuvulus have a traditional way

of catching fish from the deep.

They tie a strip of leaf to a stone

and use it as a weight to lower the line down

to 200 meters or more.

(calm music)

After that, it's simply a waiting game.

(thunder rolling)

Next morning, a tropical storm is brewing.

(dramatic music)

Despite the difficult conditions,

the crew continues to prepare the sub for another dive.

They want to get as close as possible to the shore.

Then the plan is to follow the coral reef wall

down into the deep.

(dramatic music)

Once underwater, they're sheltered from the storm above.

And they discover that the reef drops straight down.

Surface Nadir, passing through 60 meters.

Conditions are good, visibility is good.

We're on the face of the wall.

They head for the location

pointed out by the fisherman.

Let's go down here.

A large fish is lurking inside a crevice,

could it be the coelacanth?

No, it's not.

It's a kind of grouper fish.

The team seem a bit disappointed.

(exclaims)

But then, a massive grouper swims

right up to the sub's window.

(foreboding music)

It's a giant, maybe a meter long.

(foreboding rolls)

As groupers mature,

they are known to move into deeper water.

It peers into the sub, fascinated by the alien visitors.

This is a novelty even for Ardmann.

(foreboding rolls)

(calm music)

Surface Nadir, depths, 200 meters.

All systems good.

It's the fisherman's anchor, you see that?

Oh, yes.

It's the weight from a deep sea line.

This maybe the place

where the fisherman caught the coelacanth.

(mysterious music)

Might be a stuck sea lily right there.

(mysterious music)

It's another sea lily

confirming that they're now entering the twilight zone,

the threshold into the lost world.

Creatures like this are few and far between.

These waters are barren, sustaining very little life.

(mysterious music)

But something is floating towards the sub.

(mysterious music)

(indistinct talking)

They's like that for sure.

(mysterious music)

It's a nautilus, another living fossil

once common in the shallow seas

but now, largely confined to the deep.

Surface Nadir, we have a nautilus.

Its large shell contains

gas-filled flotation chambers

with much it controls its buoyancy and depths.

And it moves by squirting water out through a siphon,

a form of jet propulsion.

The team have already had superb views

of two primeval creatures,

it's a promising beginning.

(mysterious music)

They're now at a depth of 200 meters.

Ardmann notices that the surrounding seascape

is gradually changing.

(majestic music)

Still looks like the twin here,

(mumbles) of caves.

It's (mumbles), is it?

The rocks are riddled with holes.

These caves are formed thousands of years ago

by wind and waves eroding the limestone cliffs

of a small island that is now sunk beneath the sea.

(mysterious music)

There could be a coelacanth hiding in one of these crevices.

The team decides to embark

on the systematic search of the caves.

Day after day, they dive for eight hours at a time.

But it's not easy to find a fish hiding in the dark.

Getting the sub close to holes and crevices

in strong currents is a challenge.

It seems an endless task as they check hundreds of caves.

Nothing seen.

Have coelacanths already been fished

to extinction in these waters,

or are they too shy to reveal themselves?

(gentle music)

It's frustrating and they have nothing to show

for their efforts but sheer exhaustion.

The team faced a difficult decision.

Should they stay or move to another site?

After much consideration, Ardmann decides

to take his chances on the new location.

They head east towards the Kaniet Islands 200 miles away.

(gentle music)

Far out in the Pacific, the Kaniet islands

are still uninhabited.

(gentle music)

Untouched by man, the coral reefs are healthy

and well preserved.

(gentle music)

And the water is rich in marine life.

(gentle music)

Ardmann hopes that here in these pristine waters,

they may find the creature they're looking for.

(gentle music)

The sub descends into the crystal blue water.

The team have their hopes set high.

Even at 200 meters, the light still penetrates.

The water is exceptionally clear.

Wow.

Oh, they're all around us, holy shit.

They're everywhere.

The team are astounded

by the sheer numbers of fish at these depths.

It's unlike anything they've seen before.

(gentle music)

Suddenly, they come across a whole complex of caves.

Catacombs in there.

Jesus.

(gentle music)

Openings large and small

lie in the surface of the rock.

(gentle music)

Some are so large that the submersible

could easily fit inside.

(gentle music)

A large grouper disappears into a hole.

This place definitely has potential.

(gentle music)

Great point was rich with interesting caves

but strong current.

To find their quarry,

Ardmann has brought along a new gimmick.

It's a compact camera called the drop cam

that can be taken down into the deep.

The back of bait is tied to the front of the camera.

Oh, but it goes straight there.

And within minutes,

it's attracted attention.

Oh, no, no (laughs).

(exclaiming)

That's the end of our--

A huge grouper has ripped the bait bag

right off together with the arm of the rig.

Oh, Jesus Christ.

Surface Nadir, we were just attacked

by a very large grouper and he tore the whole bait arm

of the front of the frame.

(upbeat music)

Back on their mother ship,

the technicians hurried to build a second system.

(upbeat music)

They managed to assemble all the parts

and even replaced the frame with a sturdier one.

(upbeat music)

Is that okay?

Okay.

The camera is rigged again

and the contraption will be left for the next 24 hours.

The drop cam uses red light

the deep-sea creatures can't detect.

This should allow us to see the animals behaving naturally.

A nautilus has been lured in by the bait.

And it's soon joined by another.

(cartoony music)

The new comer seems to be watching the first with interest.

(cartoony music)

Now, it's trying to pull the first one off the bait.

(cartoony music)

With a strong arm tactics and jet propulsion,

it wrenches its rival off the food.

(cartoony music)

It's a surprisingly vigorous battle

between these two living fossils.

(cartoony music)

Down in the deep, food is so scarce

that every morsel is heavily contested.

(cartoony music)

The large bag of bait continues to attract others

and is soon the center of a feeding frenzy.

(cartoony music)

(suspenseful music)

It's the last day of the expedition.

Aboard the Alucia, preparations are underway

for the final dive.

The dome is given a good clean

and the crew also decides to change the lights on the sub.

One light is replaced with a red one

since it works so well with the trap cam.

He'd made decrease visibility a little

but it will ensure that they don't scare off the animals.

Still optimistic.

We don't get the mare, looking forward to this last dive

and crossing fingers we get to it on the last dive.

It's happened before.

(questing music)

Surface Nadir, depth 210 life spawn okay,

heading south.

They have entered the twilight zone.

It's time to switch off the bright lights

leaving only the red.

(questing music)

It's working.

The fish seem unperturbed by the large sub above them.

And then.

(mumbles) has gotta go from,

he really is (mumbles)

This is gonna be awesome.

(exclaiming)

A massive grouper attacked the fish.

A ferocious predator like this would like to scare off

any coelacanth in the area.

(questing music)

Ardmann decides to take the sub down even further.

(questing music)

Surface Nadir, depth 275 meters,

last border cave.

(questing music)

This deep, it's virtually pitch-black

and there's almost no sign of life.

(questing music)

It seems unlikely they'll find anything here.

Just as the crew are debating whether to turn back.

There's a fish there having bright eyes.

Wide eyes.

You like the wide eyes.

You know what fish has wide eyes.

Very suspicious.

Then you go straight to that.

It's a big tube, whatever it is.

Oh, there's a couple of them.

Oh, shit, is this what, this could be it.

This is coelacanth.

This is it, mate.

Yeah.

We've got him (laughs).

High five!

Good boys.

We nailed him.

Where?

Right?

At least I think that, well, oh, let's make sure,

let's make sure, let's make sure.

My God!

Oh, they got something.

Yeah, it's them--

Are you sure, 'cause there's something else?

There's something, they've got a weird something on it.

What is this?

Well, that's a cast--

That's not a coela, that's something else.

But maybe right behind it, I--

Bizarre animal though, look at it.

Oh shit.

But there's a second above which--

You gotta film this.

(laughs) You gotta film this.

It's a creature Ardmann has never seen before.

It swims slowly along the seafloor.

It has a large head like a coelacanth but a spotted body.

And beneath its belly,

there are strange appendages or feelers.

Ardmann has no idea what this fish could be.

Is it possibly a new species?

Ah, I thought we had a--

What do we gotta call this fish?

An unknown species?

Talking of weird fish.

Man, look at these things.

Surface Nadir,

we have two coelacanths-looking fish.

Variety, unknown.

There is astonishment in the control room.

It sounds like, they have just found a new fish,

so it looks very much like a coelacanth.

(machine operating)

That dorsal fin is exactly

carbon copy of a coelacanth.

The strange fish shows little sign of fear

even when the sub moves in closer.

A second one is lurking further back in the shadows.

(mysterious music)

Ardmann is fascinated and decides to follow

the mysterious creature.

(mysterious music)

But then to their surprise,

the fish starts to swim towards them.

It appears to be interested in the sub.

It's a close encounter of their third kind.

(indistinct talking)

Wow, that is close.

He thinks we're shelter.

So it's about 1.2 meter of fish.

And the other?

1.2, 1.--

It's a weird fish.

As it passes overhead,

it clearly extends its curious appendages.

(gentle music)

Could it be using these to feel the surface of the dome?

(gentle music)

And then, it even swims upside down.

(gentle music)

It clearly has three antennae-like structures

on both sides of the body.

(gentle music)

It's, wow!

They look like that tripod.

Feelers on the bottom here at the animal.

(gentle music)

The fish appears to stroke the rock

with its antennae as if exploring the surface.

(gentle music)

The longest antennae extend just beyond the fins

and the animal is able to move them at will.

(gentle music)

The tips of the strange feelers flatten out to a point

and seem to be soft and tactile.

(gentle music)

Should we, do you wanna do some red light filming?

Yes. Yeah?

Ardmann switches to the red light

to see if the animal will behave any differently.

(gentle music)

It heads off slowly towards the back of the cave.

(gentle music)

It seems to have lost interest in the sub

and continues with its normal life.

(gentle music)

It swims into a narrow crevice.

(gentle music)

Though they wait, it doesn't appear to be coming out again.

This must be its home.

(gentle music)

Slowly circling around, it appears to be checking out

its surroundings gently propping the walls with its feelers.

For creatures that live in the dark,

other senses such as touch become more important.

(gentle music)

Ardmann is intrigued, what is this strange creature?

(gentle music)

The crew on the surface try to identify the fish

from the information they've received from the sub.

They come to the conclusion that it might be a new species

that was only recently described.

He says there's something there

but a not as pronounced as the coelacanth.

In fact, it turns out

that the fish was first discovered in Japan in 2008.

The specimen is preserved

in the Museum of Natural History in Kanagawa.

Dr. Hiroshi Senou who first described it,

explains that it's a very rare kind of deep-sea fish.

It has a skeleton made mostly of cartilage

and a strange soft gelatinous nose.

There are only four recorded specimens

of this jellynose in the world.

This is one of them.

(calm music)

Dr. Senou points out its strange pelvic fins

which are typical of the species.

They have evolved into three long, narrow fin rays

which look like antennae.

(calm music)

It's almost certainly the same fish that Ardmann

and his team encountered in the deep.

(calm music)

I think this video that we are able to capture

of the jellynose is probably in many ways more valuable

than any video of coelacanths,

given that this group is so poorly known

and there's really no existing footage

of anywhere near that quality.

In fact most of the photos and video that we have

are just simply dead specimens,

so this is really spectacular footage

and I think that there's a lot that's gonna be able

to be learned about this special group of fishes.

(questing music)

The jellynose hides in narrow caves

deep within the ocean

which is perhaps why it was not caught

until the 21st century.

Even today, we know virtually nothing about it

and how it lives in the deep.

The expedition's footage provides the first clues

as to how this curious fish

may have managed to survive at such depths.

A tiny fish swims up to the jellynose

and briefly comes into contact with its sensitive feelers.

Surprisingly, the jellynose doesn't react.

(questing music)

Even though food is scarce in this environment,

the jellynose showed no sign of feeding

the entire four hours that the team followed it.

Like many deep-sea fish, it seems to conserve energy

by swimming very slowly in the cold water

and can therefore survive on very little food.

(gentle music)

But how did the jellynose come to live

in one of the most inhospitable places on earth?

Genetic analysis suggests that its ancestors evolved

in shallow seas, some, a hundred million years ago.

At first they prospered, but were then driven

into deeper water by the arrival of powerful predators.

In this impoverished environment,

they evolved to withstand periods of starvation.

And this may be how the jellynose survived the extinctions

that befell many other species on earth.

(gentle music)

66 million years ago, dinosaurs ruled the land

and plesiosaurs dominated the seas.

(powerful music)

A gigantic meteorite, 10 kilometers in diameter

collided with our planet with catastrophic consequences.

(explosion)

The intense heat burnt over half the earth's forests.

(explosion)

(waves splashing)

Giant tsunami swept across the continent.

(waves rushing)

(dramatic music)

It may well be this that wiped out the dinosaurs.

(dramatic music)

(heavy raindrops falling)

The shock waves of the impact released underground sulfur

into the atmosphere which turned into deadly acid rain.

The sulfuric rain killed off the plankton

in the shallow seas

and many marine animals including the plesiosaurs

are thought to have died of starvation.

(dramatic music)

The acid rain, however, never reached the deep.

It was neutralized by seawater on the way down.

(dramatic music)

So many creatures that lived in the deep seas

were able to survive.

Already adapted to living in the sparse environment,

these animals now had an advantage.

(powerful music)

Moving slowly to conserve energy

and able to endure periods of starvation

helped the ancestors of the jellynose

to survive in the deep.

That certainly is Ardmann's theory.

It's clearly something from the lost world.

It would appear that these animals actually have a,

an ecology or behavior which is very similar

to the coelacanths, so it's dwelling inside of caves.

It's well camouflaged against the back of the cave

hovering there, but then if it's disturbed it will come out.

From our limited observations from the submarine,

it appeared that these fishes really are probably

quite dependent on the caves where they're living.

So I would say that the caves are probably

a very important part of their habitat.

(calm music)

The yearlong research has come to an end.

Ardmann and his team have discovered a lost world

of pre-historic creatures still living in the deep waters

of the tropical seas.

(calm music)

A nautilus, virtually unchanged for 400 million years

slowly bobbing through the dark water.

(calm music)

And sea lilies standing tall on the ocean floor.

(calm music)

It's a world where time stood still

and living fossils survive.

(dramatic music)

This barren environment where most marine creatures

could not survive has cradled these ancient animals

in a virtual time capsule.

(gentle music)

Exploring these tropical seas

just 200 meters below the surface,

we found a very unique and special place

unlike anything that I've ever experienced before.

The deep sea of course is a very vast area.

Interestingly, very little explorations ever been done

in this region and it's largely still a mystery.

But by using cutting-edge technology

like the Triton submersible,

we've been able to really shed some light

on this very unique place

and understand much better this lost world.

(dramatic music)

The astounding encounter

with the bizarre fish, the jellynose

that leads a austere life in the dark waters

was the highlight of the expedition.

(delightful music)

It was revealed that the deep sea still remain

a mysterious and unexplored world.

(delightful music)

Over 90% of our oceans are so deep

but they're normally far beyond our reach

and they remain the least known part of our planet.

(delightful music)