Throughout our history, one creature above all others...
has haunted our imagination.
On land and in the air...
the dragon has left its mark in the folklore of our ancestors.
But what if these fantastic stories were more than myth?
What if the legends were true?
This is the story of a unique family...
that survived from the time of the dinosaur...
to make a final stand in the Middle Ages.
A scientific exploration of a remarkable species.
This is the natural history of the most extraordinary creature...
that never existed.
The Cretaceous Period.
A time when the world was ruled by the most fearsome predator...
that ever walked the Earth:
Tyrannosaurus rex.
The T. Rex has been forced to this remote place...
from his usual hunting ground.
Something has been raiding his territory, and food has become scarce.
He hasn't eaten for days.
At last, a potential kill.
But the T. Rex is cautious.
He has never seen a creature like this before.
Hunger drives him on.
The T. Rex has a clear weight advantage.
So his prey bluffs...
extends its wings to give the illusion that it is much larger than it really is.
But the T. Rex isn't buying it.
So the creature tries a different tack.
The cry carries for miles.
To this predator's sensitive ears the sound is incredibly painful.
But the T. Rex is still not deterred.
And up here, there's nowhere to hide.
But it is the T. Rex, not his prey, that is fatally exposed.
They are not alone.
This is an adult female.
A fully grown prehistoric dragon.
This is her territory and she's protecting her son.
The Tyrannosaurus will not last the night.
But the mother is also seriously injured.
With a broken wing, she can no longer hunt...
to feed herself or her offspring.
But 65 million years from now...
the T. Rex's skull will inspire a theory...
in the mind of a brilliant young paleontologist.
This is one of only three intact T. Rex skulls...
that have ever been found.
It all started five years ago...
when I discovered this complete T. Rex in Montana.
It was big news.
Dr. Jack Tanner, paleontologist...
an overnight celebrity.
But then I blew it.
I proposed the existence of an impossible creature.
You see, my T. Rex skull was damaged in a very specific way.
To me, the injuries were evidence...
of an attack by a predator unlike anything known to science.
The evidence was undeniable.
So I tried to get others to see things my way.
The nature of these marks suggests...
that this skull was punctured by three sharp objects...
in an arc.
It's a talon formation.
But I don't believe that these puncture wounds...
actually killed the rex.
The real deathblow is here.
See?
Symmetrical deposits of carbon down both sides of the skull.
These are scorch marks. Precise, aimed.
Perhaps my childhood obsession had clouded my thinking.
You see, as a kid I was mad about dragons.
Dragons from the high seas, flying dragons from Greenland...
fire-breathing dragons from Europe.
And here's the thing that got me:
These myths came from all over the world, right?
From cultures that could never have met.
And yet from the Andes to the Himalayas you could hear stories of dragons.
How?
Here's a kid's best guess: Because the stories were real.
Last week, guess what?
Out of nowhere, the dragon man is thrown a lifeline.
Another find, not Montana this time...
but on a Romanian mountain.
Extreme skiers had fallen into a network of ice caves.
They found something horrific.
A body, and it wasn't wearing the latest lightweight thermals.
It was ancient.
There's nothing the police could do with a 15th-century corpse.
This was a case for historians not detectives.
But police being police, they couldn't resist a nose around.
They uncovered a medieval crime scene.
A massacre.
They moved deeper into the cave...
and soon wished they hadn't.
Now I don't know the Romanian word for dragon...
but someone said it.
So the Romanians contact the museum in London:
"Is this thing a hoax or what?"
Now the museum, they're ready to pass.
They have an international reputation to maintain.
I get to hear about it and figure I'm the perfect solution.
The man with no reputation to lose.
Have you seen the pictures?
Every head of department has seen the pictures.
And?
The museum's been formally asked by the Romanian authorities...
in the strictest confidence, to help with this find.
It's got them in quite a state.
They don't know what they've got and neither do we.
Can I go? On the museum's behalf.
I can call a meeting.
So here I am with two of the museum's rising stars...
who see me as a bad career move.
We've got strict orders: If this thing's of any interest...
get it shipped back to London.
If it's a hoax, make our excuses and leave.
If news gets out, I'm the fall guy.
Either way, I lose.
Unless, by one chance in a million...
it's not a hoax.
Maybe then I get my reputation back.
It starts badly.
They've moved everything off of the mountain.
Who knows what evidence might have been disturbed.
So we're in the backwoods...
at a makeshift mortuary in an overgrown shed.
The official word is the bodies have been blackened by ice, but I wonder.
Ask me, I'd say they have a different story to tell.
But I mind my own business. My assignment is through here.
Nobody said anything about a whole carcass.
It's massive.
I can see why the Romanians were cagey.
I should be, too, if I had any sense.
This has got to be a hoax.
Hasn't it?
Okay, so let's get this over with.
12:05 p.m. June 25.
Dr. Tanner and team are forced to begin an immediate examination...
of an unidentified animal.
The skin looks real enough. Too well preserved?
If this is a hoax, it's the best I've ever seen.
Okay, sweetheart. What are you?
The hide is scaly.
It has a tail.
Now, both suggest that this is some sort of reptile...
and yet there are two limbs visible, ending...
with what appear to be talons.
Now these are general characteristics...
Characteristics of powered flight.
Could this thing really fly?
It's too heavy for these small wings.
They couldn't create nearly enough lift to get its carcass off the ground.
You see, to fly you have to obey the laws of physics.
There is a relationship between weight, power, and wingspan.
Wing measurements give us wingspan under 20 feet.
It's not enough.
This creature looks built to fly, it's got all the parts...
but at the moment they just don't add up.
- Estimated weight? - I'm guessing 900 pounds.
Maybe 950.
He's not gonna like this.
Don't tell me.
The wing-to-weight ratio is way out. Couldn't fly, right? It's too heavy.
A creature with wings that can't fly.
That spells trouble.
Two weeks have passed since his mother saved him from the T. Rex...
and the young dragon is in trouble.
His mother is dead.
The injury to her wing proved fatal.
He cannot fly and with no one to hunt for him, he, too, will die.
The smell from his mother's carcass is attracting scavengers.
For the moment they're just pterosaurs...
but who knows what other creatures may pick up the scent.
This dragon lost his mother at a critical moment.
Somehow, he has to teach himself to fly before it's too late.
And if he does get airborne...
it will be thanks to one of nature's most astonishing feats of engineering.
This just gets stranger by the minute.
Internal scans show a massive heart.
That's typical of flying creatures.
Those chest muscles would need large quantities of oxygen-rich blood.
Your bones are perfectly designed for flight, too.
The internal structure is very specialized. It's honeycombed.
You see this lightweight structure in bird skeletons.
Their bones are strong but still light enough for flight.
But you're too heavy for those wings.
Come on. What's your secret?
Any good news?
There's something unusual inside the chest cavity.
What are these?
The image is too fuzzy. We don't have time to speculate.
I'm going inside.
The plot thickens.
A second pair of lungs?
But there's no internal structure. Bladders, maybe?
They must have held something.
Can you pass me a syringe please?
Thank you.
It's gas.
Analysis, please.
Unable to hunt, the young dragon exploits the only food available to him.
His mother's meat will keep him alive for a few days.
But if he can't fly, he can't hunt.
His future looks bleak.
Yet, even in death, his mother may still help him.
In their gut, all creatures contain bacteria...
that help them to break down food.
And as they do this, they release gas.
But the bacteria inside dragons are unique...
and the gas they produce is special.
It is channeled into two storage chambers:
The dragon's flight bladders.
Alongside the super-light skeleton, these bladders provide the key to flight...
provided you know how to use them.
This young dragon will have to learn fast.
The scent of his decomposing mother...
has attracted the most dangerous creature imaginable:
An aging male dragon.
Its broken horns and dull markings betray a dragon at the end of his days.
And this is bad news for our juvenile.
Continuous battles over territory mean that most males never reach old age.
But this dragon is still around.
He's a survivor and he's hungry.
The youngster senses that, given the choice, he'd prefer fresh meat.
And this time his mother isn't there to save him.
His only hope is to take to the air.
Okay. Gas composition.
Predominantly hydrogen.
Hydrogen.
It's 14 times less dense than air. It's odorless, colorless.
You put hydrogen in a balloon, what happens? It floats away, right?
The juvenile heads for the trees. The old male cannot fly here.
Inside, the young dragon's body is working overtime.
Heart beating, muscles pumping...
and hydrogen is collecting at a phenomenal rate.
Fully expanded, what would you say is the cubic capacity of one of these things?
- 15 cubic feet? - There are two. That's 30.
30 cubic feet, all pumped full of hydrogen.
What kind of lift does that give us?
Not quite there, but maybe.
The youngster's flight bladders are now full...
but crucially so is his stomach.
The undigested meat is weighing him down.
Just in time, instinct takes over.
He empties his stomach...
and spreads his wings.
Exhausted, the old male abandons the chase.
Our young dragon has found his wings...
just in time.
And for the very first time in his life.
Analysis suggests, it's to be confirmed...
that maybe, just maybe...
this creature could fly.
This is no hoax. This thing is for real.
A gigantic flying lizard.
Too much to expect that you can breathe fire, too.
"If it's interesting, bring it back to the museum."
That was the plan.
Well it's interesting all right.
But let's see what else we can find out before we have to leave.
Okay.
Time to put our heads into the lion's mouth.
It was clearly a carnivore.
A formidable predator.
What's going on here? You've got incisors for ripping meat...
and molars, grinding teeth.
Stingrays have the same kind of teeth for crunching rock-hard shells.
What would a meat-eating predator want with teeth like these?
Several years have passed and our juvenile is now a young adult.
But he is homeless.
Without territory, he will never have a regular supply of food...
and he will never mate.
But his time has come.
In the past he has strayed accidentally inside the territory of dominant males.
Today there is no mistake.
It is a daring act.
Half of all young males are killed in territorial battles.
The dull coat of adolescence...
has transformed into a vibrant display...
designed to intimidate rival males.
But before he makes himself known...
he takes on stores of a rare and valuable mineral...
found at the heart of every dragon territory.
He is preparing for the fight of his life.
And these rocks will hold the key.
The inner surface of the mouth is incredible.
It's almost armor-plated.
Now this is something I've definitely seen before.
A fleshy valve at the back of the throat.
This flap is very similar to the false palates found in crocodile throats.
Crocs use it to stop their lungs from flooding...
while holding prey underwater.
It's a very distinctive shape and come to think of it...
I think I've seen fossils of this somewhere.
This is a highly specialized structure.
Can you scout the excavations and dig sites and museums...
to see if anything like these bones have popped up anywhere else?
Maybe it's an adaptation.
Maybe it wasn't used to prevent water flooding the lungs.
Maybe it's to prevent a backdraft of fire...
from burning the throat.
Boy, when you say it out loud, does it sound lame.
It doesn't look like fire ever came out of this creature's mouth.
There's no carbonized food residue, no signs of charring whatsoever.
It's as if all the tools are here, they just haven't been used.
Perhaps it didn't breathe fire at all.
Well, maybe you're right.
Let's take a step back.
Nature isn't constrained by our lack of imagination.
Think about it. The natural world is full of bizarre creatures...
that have the most extraordinary weapons:
Tongues like spears, colors that change...
and shapes. Lassos, even.
But a creature that breathes fire?
Bear with me.
Meet the bombardier beetle.
When this guy gets angry it fires out liquid...
at a temperature of over 200 degrees Fahrenheit.
How does he do it?
By pumping a liquid fuel into a reaction chamber...
where a catalyst ignites it.
The exploding chemicals have nowhere to go but out...
and with a bang.
Is that how dragons did it?
In the heart of his territory, the resident dragon, the alpha male...
blasts a warning into the air.
It signals that he is fit, healthy, and confident enough...
to waste precious fire on a display.
The message is not lost on our young challenger.
If he has any chance at all of winning this duel...
he must be at his very best.
Because the stakes are high.
With territory comes not only a guaranteed supply of food...
but the one thing every young male needs...
if he is to leave his mark on the next generation:
Females.
And this female is the reason he is here.
She's in season and for just one month will breed with the alpha male.
He's killed for her before and he'll do it again.
Okay.
Back to basics.
What do we need to produce fire?
We need fuel and we need something to light it with, an ignition system.
We need a light, combustible material.
Like gas?
Now what did you say was in these things?
Hydrogen and methane?
How could I have been so stupid?
I need a light.
This is hydrogen and methane.
Both combustible gases, both lighter than air.
These sacks double up as buoyancy aids...
and fuel stores.
Evolution at its most economical.
So far, so good.
But how did you ignite it?
Could I take a sample please?
The alpha male is an experienced warhorse.
With nothing to prove he's lost the bright colors...
that mark out the young challenger.
Experience tells immediately.
The alpha male catches our youngster with his first strike.
Instinctively, the young dragon heads for cover.
The cold damp clouds will also dull the pain.
But the alpha male is not without his problems.
These dogfights are calculated affairs.
The hydrogen in his fuel tanks also has to keep him airborne.
Every blast of flame reduces his mobility.
The challenger appears to accept defeat.
He heads for the territorial boundary.
It seems that now his best hope is to escape with his life.
The alpha male drives on. He would rather finish him now.
But he has misjudged his young opponent.
The youngster is faster, more agile...
and, crucially, he has a full payload to burn.
Wouldn't you know it!
That sediment on the creature's molars, it's rock...
with particularly large traces of platinum.
Platinum is not just a precious metal, it's also a catalyst.
Like our old friend the bombardier beetle, fuel needs an ignition system.
And when platinum combines with oxygen and hydrogen...
it combusts.
It produces fire!
Our young pretender has triumphed.
The female prepares to accept her new dragon overlord.
All his life he's fought the odds and at last he's made it.
My theory was right after all, and you're the proof.
You could fly. You could breathe fire.
65 million years ago, one of your ancestors killed my T. Rex.
So how did your ancestor survive when the dinosaurs didn't?
The natural history of our planet tells me...
that it simply couldn't have happened.
65 million years ago, at the peak of our dragon's success...
a curtain comes crashing down on The Cretaceous Period.
A meteorite the size of Mount Everest smashes into the planet.
Known as the K-T event, it wipes out nearly all life on Earth.
But somehow your species did survive.
How?
If the K-T meteorite finished off the dinosaurs...
how did a giant species like yours survive?
Let's think straight.
What other large creatures survived K-T?
Sharks, skates, rays, turtles, coelacanths amongst others.
- All have in common? - They're marine life.
And crocodiles, too.
Crocodiles.
The false palate is found in crocodiles.
Raised nostrils, suggesting a creature that could hold its prey in its jaws...
and breathe while completely submerged in water.
But this creature didn't swim, it flew.
It has wings and talons, not webbed feet...
suggesting the palate must be an evolutionary relic.
Somewhere in the dim and distant past...
this creature's ancestors lived in water.
You swam from extinction.
Water did indeed provide dragons...
with the escape route from one of the deadliest events in Earth's history.
But not the Prehistoric Dragon.
The land-living dragon was indeed wiped out.
But it was not alone.
The dragon family had another branch.
At the time of the K-T catastrophe, the Prehistoric Dragon had a cousin:
The Marine Dragon.
Both species were descended from a common ancestor.
But they followed very different evolutionary paths.
The Marine Dragon lived in the sea...
and life in the sea was less affected by the K-T event.
As they evolved, their flight bladders became swim bladders.
Their large wings reduced to become fins...
and their powerful tails became rudders.
Marine Dragons thrived.
Then, as global temperatures rose and the land recovered...
some Marine Dragons returned to shallow waters.
Through estuaries and rivers...
they eventually made their first tentative steps back on to land.
The sea serpent.
Are the legends actually about Marine Dragons?
That false palate. Guess what?
Looks like it's turned up at a dig site.
This could be our missing link.
What kind of environment are we talking about?
Forest.
- What kind of forest? - Bamboo.
I knew I'd seen the palate before. It was in that excavation in China.
I thought it had been from an extinct branch of crocodilian.
Turns out to be much more exciting.
So the Water Dragon came back on land and evolved into new species...
at least one of them in Asia.
Forest-dwelling. What would you be like?
Well, in Chinese mythology...
dragons are low-slung, elongated, slender.
The kind of body one would expect from an animal...
that's recently adapted from water.
Was it really suited for life in a forest?
The dragons that return to land...
discover that the prehistoric world has changed.
The era of the dinosaur is over...
and a new order of animals has risen up to fill the void:
Mammals.
And mammals provide plentiful food for dragons.
The trick is to catch them.
The superb camouflage and silent movement...
has made this dragon all but invisible in the bamboo forest.
The wings on this dragon are too small for flight...
but the flight bladders provide gentle lift...
and allow her to glide silently across the forest floor.
The markings on her skin break up her outline...
in the dappled forest light.
And to be sure, this massive relic from the age of the dinosaur...
has had to develop new tricks.
Hunting mammals in this compact environment...
requires tremendous guile.
Small, fast, and agile...
mammals have incredibly acute hearing and smell.
Alerted, they can disappear in an instant.
Positioning herself downwind from her prey...
she lies in wait and listens intently.
But she's not ready to strike just yet.
Not before unveiling a highly specialized weapon...
that gives her an edge against this wary prey.
The Forest Dragon has developed a remarkable behavioral strategy:
Mimicry.
By carefully controlling the flow of gases from her flight bladder...
she manipulates her voice and entices her prey.
But her hunt is disturbed.
There's an intruder in her territory.
A creature that will come between this dragon and her prey for the last time.
It's not just the invasion of her territory that riles her...
or the loss of the odd meal.
This animal is a real and emerging threat to her very survival.
A glide is the best her stunted wings allow.
But she has the scent now and is determined to finish things.
Smaller and more mobile in the forest undergrowth...
the new mammalian predators are proving to be accomplished hunters.
Left alone, these predators will out-compete her for food...
and she would starve.
She isn't going to let it happen.
The dragon closes to striking range.
She blends into her surroundings, unseen but not unheard.