Original subtitles

Predators across the planet.

Unmatched in strength...

...speed, strategy,

stealth...

...and teamwork.

But staying on top is never easy.

As the world around them changes,

they must adapt faster than ever before

to maintain their rule.

In Tanzania's Serengeti, a notorious brotherhood of cheetahs.

They command this vast hunting territory.

But their status is under attack.

Rivals are closing in.

The battle is no longer just to stay on top...

...but to stay alive,

as they try to cling on to their mighty alliance.

For the past six years,

male cheetahs Luka and Kovu

have held their territory here

in the southern plains of Africa's Serengeti.

Kovu, with his scarred nose,

is a cunning and meticulous hunter.

The brains of the operation.

While Luka, with his muscular frame,

is a creature of brute strength.

They're always at each other's side...

...but they're not brothers.

They were born 80 kilometres apart.

As young males, their paths crossed.

And through many years learning the rules of the savanna together,

their unbreakable bond was forged.

While females are solitary, male cheetahs band together.

But Luka's raw power, combined with Kovu's sharp mind,

has made them a double act like no other,

seeing off all rivals and dominating the largest prey.

Now eight years old,

the pair are fiercely territorial.

The hunting grounds they hold

are 50 square kilometres of rolling savannah.

There are rocky outcrops for cover...

pools to drink from...

and every year it floods with herds of zebra,

wildebeest, and gazelle.

They fiercely defend this territory from neighbouring males,

so any females that come here are theirs alone to mate with.

They are the epitome of an apex predator,

and the success of the entire population

relies on strong males like them

mating, and passing on their genes.

Luka and Kovu have become masters of this game.

But the rules of their world are changing.

It's August,

and the Serengeti's dry season is kicking into gear.

The sun scorches the grass,

herds are heading north to find water,

and the predators that remain are fighting over a shrinking supply of food.

But the twist of the knife

is that, for three years, the region has been plagued by drought.

The dry season months of June to October

have been getting hotter and hotter.

As Luka and Kovu's world becomes a hostile tinderbox,

guarding their patch is more crucial than ever.

So their rules are clear:

intruders keep out, or be killed.

But eight kilometres away...

...at their territory's western boundary...

...there's been a breach.

A gang of four powerful sons,

led by their imposing mum,

known as the Solaro family.

They have swagger and strength in numbers.

Even the hyenas seem to sense their power.

Watching Mum stalk gazelle,

the sons are fast learning the ways of the hunter.

For now, the four sons remain at Mum's side.

But any day now,

this band of brothers will leave as a coalition,

to stake their own territory.

There's no way Luka and Kovu can allow the Solaro sons

to share their patch.

In this drought, there won't be enough food to feed them all.

But against four males,

they'll be dangerously outnumbered.

The one thing that could help them

is far from here...

...160 kilometres to the north,

over rivers, and valleys...

...a mega-herd of 1.5 million wildebeest...

and zebra are on the move.

The pregnant females need to graze constantly to make milk.

When the rains return,

the plains in Luka and Kovu's territory

are where the sweetest grasses will grow,

so the herd must travel there.

When the herds arrive, there'll be enough zebra and wildebeest...

...to feed all the cheetahs across this region...

...and no need for the Solaro sons to encroach.

But it's not that easy.

Blocking the herd's path like a slick, black serpent...

...the Mara River.

Steep banks...

...deep water...

...no way round.

As the bankside swells with bodies,

their migration may have reached its limit.

If the herd can't reach the southern plains,

Luka and Kovu won't just go hungry,

they may face a turf war with the Solaro brothers.

But right now,

the boys have a bigger problem...

Smoke.

The drought has left the grass bone dry.

It ignites with terrifying ease.

Luka and Kovu have seen wildfires before.

They know they can spread with devastating speed.

As the heat rises,

they can only watch the inferno in disbelief.

There's nothing they can do.

They need to retreat to a safe haven.

As the fire blazes unchecked,

those who can't run, hide...

...while white storks descend

to make a quick meal of the insects escaping the blaze.

The flames tear through the heart of Luka and Kovu's hard-won territory.

Everything they have worked for may be about to slip away.

By morning, the fire's burned itself out,

and their entire territory is transformed.

Just scorched earth remains.

A hyena, singed and blistered by the fire,

slurps at a nest of baked ostrich eggs.

The mongoose emerge to an empty landscape.

The last of the gazelles have left.

Until the rains return,

this once-rich territory will remain barren.

The boys have no choice but to abandon it.

With no territory,

finding food will be a huge challenge.

And their ability to attract females is now near to none.

They must try to find a new ground,

but it's a crowded landscape.

If they head east,

they'll go beyond the boundary of the grasslands,

to where farmers kill cheetahs to protect their livestock.

So their only option is to head west,

deep into the Serengeti's heart.

A place ruled by hyenas,

lions and rival cheetahs,

all vying for the same food.

The duo's fate now rests more than ever

with the arrival of the wildebeest and zebra.

140 kilometres to the north,

the herd calculates its next move.

For their survival, they need to cross.

But a flotilla of crocodiles is lying in wait.

They are the apex predator of this water world,

and they've not eaten for months.

The elders who have run this gauntlet before know timing is everything.

There are no second chances.

The wet rocks become a perilous slick

that can snap legs and crack bones.

The walking wounded limp to safety.

Those too badly injured

are defenceless against the advancing crocodiles.

But while the crocodiles have their mouths full...

...hundreds of thousands more make it through.

With their noses to the wind, they push on south.

For Luka and Kovu, these herds can't arrive soon enough.

It's now September,

and the drought is tightening its grip.

Lions shelter from the midday sun...

marauding hyenas patrol the plains...

...and the Solaro Family are closing in,

now skirting past the scorched territory

once held by Luka and Kovu.

Oblivious to the threat trailing them,

the pair are now trying to adapt to life on the move,

as they continue searching for a new home.

Ordinarily, they'd get the water they need

from the prey they eat.

But with hunting opportunities so scarce,

the boys are desperately thirsty.

The problem is,

the few watering holes that haven't dried

are now crawling with lions.

There's no way the pride will share this precious resource with cheetahs.

Eventually, they reach an unoccupied pool.

But the drought has impacted everything.

A single drop is enough to tell Luka that the water is putrid

and not safe to drink.

There's nothing for the boys here.

Dust chokes the air...

...and giraffes scour the trees for the remaining green leaves.

The duo's search for a new territory

brings them to a barren plateau.

There's no sign of the large gazelles they would ideally hunt,

but it's no time to be picky.

These hungry boys will eat whatever they can catch.

Kovu senses there's food hiding here.

They both scan the scrub, searching for clues.

The black stripes beneath their eyes absorb the sun's glare,

enhancing their vision.

Their hunting instinct is triggered by the slightest movement.

So if the hare keeps still...

...it could go unnoticed.

Close call.

But Kovu clocks it!

♪ MUSIC FADES

Even a lightning fast hare can't escape

the fastest animal on land.

It's not much,

but the hare is a lifeline to keep Luka and Kovu going.

And they'll need all the energy they can get.

Their journey has now led them to within a kilometre of the Solaro family.

If their paths cross, it's bad news.

Only if the migrating herds arrive soon

will there be enough food to avert a bloody turf war.

The herds are now only 110 kilometres to the north...

...but there's a snag.

The fresh grass they're after in the southern plains

is triggered by the first rains.

But the rains are late,

so the herds have stopped in their tracks.

In previous decades,

the wet seasons here arrived like clockwork.

But those days are a distant memory.

For Luka and Kovu, it's a disaster.

Walking north to intercept the herds is not an option.

They'd have to trespass dangerously

through many rival cheetah territories.

They're running low on food,

and their competition...

...is closing in.

Right now, the four Solaro sons

remain at mum's side,

absorbing her skills as a hunter.

She too is resigned to taking hares.

But a single hare can't feed five large cheetahs.

Snatching it for herself is a signal to her sons:

it's time for them to leave

and find a territory of their own.

They're now old enough to hunt for themselves,

but in these extreme dry conditions,

they won't last long without mum's expertise.

The hungry sons protest.

Mum gives in.

Their bony bodies reveal that even this powerful family

hasn't escaped the grip of the dry season.

Their cracked fur is a sign of sickness.

Until the sons regain their strength, Mum must continue to fend for them.

But she won't be able to keep them all fed for much longer.

The blistering October days tick by,

squeezing the life from the land.

Thirsty elephants trudge through on their long march to find water.

Luka and Kovu are surviving almost entirely on hares now.

They end each sitting by cleaning each other's faces.

Not a drop of food can be wasted.

It is a tender ritual they share

to show their utter devotion to each other.

But for the Solaro family,

things have gone from bad to worse.

Their sickness has intensified,

and the skinniest son is now a wasted figure

of mere skin and bone.

Cheetah brothers share an unbreakable bond.

The thought of deserting him is inconceivable.

They must keep moving.

But with every step, he's getting weaker.

The family wait patiently for the sick brother to catch up,

willing him on with their cries.

Mum's tried to find food,

but their slow progress in these drought conditions

has made hunting impossible.

The whole family are slowly starving.

There's nothing his mum and brothers can do.

For their own survival, they must hunt.

They've now no choice, but to do the unthinkable,

and leave him.

Abandoned,

the sick cheetah's fate...

...now rests in nature's hands.

A kilometre away in the neighbouring valley,

fortune may have once again swung in Luka and Kovu's favour.

With the Solaros weakened by sickness,

their threat to the boys is fading.

If they are going to take a new territory,

now is the time.

The tides have turned.

Luka and Kovu have defied the drought.

And as December looms,

salvation is on its way.

Four weeks later than usual,

fat raindrops bathe the land.

It's a welcome opportunity for Luka and Kovu

to clean their dusty bodies.

The smell of the rain drifts on the wind.

50 kilometres to the north,

the herds get the signal they've been waiting for.

Time to move south.

Weeks pass...

...and the storms become more frequent.

Streams flow,

flowers bloom,

and pools fill with water,

attracting a dazzle of birdlife.

The yellowed grass gives way to a sea of green.

And swarming across it from every direction...

...the mega-herd has arrived.

Over a million wildebeest...

...together with hundreds of thousands of zebra,

hartebeest and gazelle

that have joined them to feed.

By February,

the cheetah's world is transformed.

After months of hard struggle,

Luka and Kovu's quest for a new territory is almost complete.

They've secured an area on the edge of the short-grass plains

that has everything they need,

and it's within sight of the advancing mega-herd.

But there's a catch.

Nomadic lions and hyena

are also flooding into the area...

...and patrolling the herds.

The boys' new patch has an abundance of food...

...but it also now has more competition than ever.

Luka and Kovu must be smart.

If the lions spot them moving in on the herds,

they'll be chased from the area.

So they select their spot and let the herds come to them.

These boys are far more than fast sprinters.

They are patient and calculating hunters.

Gradually, the herds edge closer.

The duo needs to select their target wisely.

Wildebeest come armed with sharp horns...

...and zebras pack a lethal kick.

Only the most fearless cheetahs will risk hunting something so big.

Perfectly in sync, they move in.

They goad the herd,

hoping a young or injured animal reveals itself.

A baby hartebeest that arrived with the mega-herd;

a worthwhile meal in Kovu's eyes.

But it's not alone.

It's mum wheels round to fend off the attack.

Then through the dust, Luka spies a young zebra;

a sizable meal, and much less risky than an adult.

The hunt is on.

The herd splinters.

Luka just dodges the zebra's hooves.

But the zebra is too strong.

Luka is losing the battle.

Then right when he's needed...

...his wingman arrives.

It's a remarkable show of teamwork.

Their risk of hunting large prey is rewarded.

By the time they finish,

their bellies bulge like basketballs.

Their strong stomachs will make fast work of this feast,

and in just 24 hours,

they'll be ready to go again.

The large area Luka and Kovu have secured has everything they need.

It's a prime territory,

so the duo will work hard to keep it.

Each morning they spray the termite mounds in their patch with their scent.

It works as a signpost,

telling other males to "keep out".

But on one mound,

Luka is picking up on a strange odour.

It smells like an intruder has been here.

Any threat from a rival cheetah must be extinguished fast.

They've proved they are powerful enough to secure a territory here.

Now, they need to prove they can protect it.

And the bold trespasser isn't even hiding.

Into formation, they advance.

But, at the last minute,

the cheetah's identity becomes clear.

The rival male is, in fact, a female.

Despite her frosty welcome, she wants to mate.

Female cheetahs are notoriously choosy.

They only pick males who are fit and strong.

Staking this new territory confirms the boys' healthy credentials.

This female is clearly interested,

even if Luka is getting mixed signals.

If she were to pick one male over the other,

it would fracture the boys' alliance.

Luckily, a twist in cheetah biology

means a single litter can have multiple fathers.

So, in the coming days, Kovu and Luka

can mate with her and pass on their genes.

Through their strength and teamwork,

Luka and Kovu's formidable double-act has defied fire and drought.

But unknown challenges still lie ahead.

As the human population around their grassland grows

and space for cheetahs shrinks...

...the boys succeeded in their quest to mate.

And now, a new generation is stepping out onto the plains...

...and fresh coalitions are being formed.

There is now no question

that the cheetah's apex status is guaranteed here

for many years to come.

Cheetahs...

They're fast, they're powerful,

but their existence is fragile.

Around 7,000 wild cheetahs remain in the entire world.

But in the vast expanse of Tanzania's Serengeti

lies one of their greatest remaining strongholds.

For almost 50 years, the Serengeti Cheetah Project

has studied the cheetahs here.

By joining forces with the project's scientists,

the Predators film crew were able to follow the lives

of multiple groups of cheetahs across the Serengeti.

And with the researchers' help, the crew documented

the story of a most remarkable partnership...

...male cheetahs Luka and Kovu.

Stabilised rigs

allowed the team to capture the male's high-speed chases.

Remote-controlled camera buggies

provided an intimate window into cheetah family life...

...and miniature drones gave a new perspective on the cheetah's world.

But while Luka and Kovu's story was one of success,

life for Serengeti's cheetahs is not easy.

So there is around 300 cheetahs in the Serengeti ecosystem

and also there's 3,000 lions...

...as well as around 6,000 hyenas.

And these other predators pose a very high challenge to the cheetahs

because they steal their kills

and kill the cheetah cubs.

That's why they have a very wide range and this helps them to dodge

or keep themselves away from other predators.

A cheetah's ability to travel many kilometres each day

to avoid conflict and find food

is part of what's made them such a successful predator.

At over 14,500 square kilometres,

the Serengeti National Park is a vast wilderness for them to roam.

So for the film crew,

trying to follow the same individual cheetahs here

over many months was a huge task.

Often for weeks at a time,

the cheetahs would seem to completely disappear into the landscape.

So at this point, it's basically a waiting game.

The Serengeti Cheetah Project must routinely monitor

these wide-ranging cats over this huge area,

so they're devising a new way to keep tabs on them.

At the moment, I'm working on deploying collars on cheetahs.

These collars have the accelerometer that can give us

the activity patterns of the cheetahs.

GPS collars have never been used before on cheetahs

in the Serengeti National Park.

So we can now track them

and they will transmit locations of where the cheetahs are.

So it's a good step

and we are really looking forward to get good results.

But even with these hi-tech advancements,

the researchers still have Mother Nature to contend with.

By the time the crew catch up with their cheetahs again,

there's troubling news.

This time of year is hard for all cheetahs, it's super-hot,

the prey is not in the densities that you get in the wet season.

But this group specifically, the mum was struggling to hunt.

We've probably watched her make sort of five or six failed hunts.

Every time she fails, she's losing a lot of energy,

burning a lot of energy that she's not replacing,

and all of her four cubs are getting pretty skinny.

But this guy, he is really, really suffering.

He's lost loads of weight. He's got wounds on his shoulders

that suggest he's also had a run-in with a hyena or something.

He can barely walk, let alone run away from hyenas if they come in.

Cheetah's rarely die from starvation alone.

Their broad diet means they can always find prey, however small,

to make it through even the toughest conditions.

But when hunger is worsened by illness or injury,

it can be a death sentence.

Yeah, he's really struggling.

Poor little guy.

The National Park's policy

is to not intervene with sick animals.

Nature must be allowed to take its course.

As night falls, it becomes clear

that the young cheetah's sickness has progressed too far.

Researchers can't save every cheetah.

But the good news is that data from the GPS collars is shedding light

on how scientists can protect the entire cheetah population.

This is the satellite data that we have been getting.

And you can see her movement.

She made a straight line here, going towards the villages.

What the collars reveal about where the cheetah go is striking.

The cheetah population have been spending most of their time

outside of the protected areas.

The revelation that the cheetahs regularly venture

into farming communities outside the protected park

is hugely significant.

Hungry cheetahs occasionally eat livestock.

And to protect their livelihoods, farmers retaliate by killing the cheetahs.

We're very concerned about what's happening to cheetahs

outside the protected areas.

When they come up against the impacts of people,

that's when you see the population start declining.

The cheetah population can't afford to lose any from their numbers.

There's only around about 7,000 cheetahs left in the whole world.

So they've suffered a really drastic collapse

over recent decades,

with the populations now only occupying

around about 10% of their former range.

With the GPS collars revealing

the critical areas outside the park where cheetahs are at risk,

vital steps can now be taken to protect them there,

paving the way for cheetahs and humans

to share this land without conflict.

This is why I play my part in the conservation

and protection of wildlife and nature.

The researcher's work is not only crucial

to safeguarding the Serengeti's cheetahs,

but a reminder that in this changing world,

to protect wildlife,

we must find ways for people and predators

to peacefully live alongside each other.

Next time...

In the frozen wilderness of Canada,

a new generation of polar bears

battle hunger in the most hostile environment.

But as their world starts to shift

they will need to overcome enormous challenges to survive.