♪♪ OYELOWO: In the story of Africa, three very different cats have come to rule three separate kingdoms.

Yet along one special river in Botswana, their dramatic stories collide.

At the height of a dry winter, water from the north begins to flood the plains.

It brings in buffalo that can feed a pride... and some dangerous young drifters that stalk in their wake.

♪♪ Hunting becomes impossible for four young cheetahs now on their own.

♪♪ And a leopard mother has two new cubs to keep out of danger.

For all our big cats, their small world is closing in.

[ Leopard snarls ] ♪♪ ♪♪ ♪♪ ♪♪ [ Birds chirping, animals grunting ] OYELOWO: We return to our cats on the shores of the Gomoti River.

It's the start of Botswana's dry winter.

And a small world is waking up.

This is the home of Molelo, lone pride male and hardworking father of 12.

♪♪ His oldest cubs were born seven months ago.

And since then, he's done all he can to keep them and their mothers safe.

♪♪ ♪♪ ♪♪ ♪♪ [ Lion roaring ] [ Roaring continues ] Molelo's roars remind neighboring males that he alone owns this world.

And these days, his voice is his strongest weapon.

He's still super confident.

But months of defending his land on his own are wearing him out.

Even walking is an effort.

There are still five months to go until his cubs no longer need his constant protection.

That's five long months of keeping other male lions out.

He's got this.

Probably.

♪♪ On this winter morning, a young cheetah named Tharo and his siblings are coming to terms with a great loss.

Since we last saw them, their mother has left them.

♪♪ Without her protection, only four of her five cubs have survived.

♪♪ ♪♪ They only have each other now to get through the next few critical months.

Young Tharo has started to take the lead through a neighborhood that is suddenly bigger, wilder, scarier, for these 15-month-old cats.

They dare not venture beyond the plains their mother taught them to live and hunt in.

♪♪ [ Birds chirping ] In the popular woodlands, a leopard named Sephiri is looking for a secluded spot to give birth.

♪♪ Hmm.

No luck here.

♪♪ While it's in her nature to be... invisible... ...she must also make her presence known.

♪♪ And this morning, she's marking out the boundaries of her nursery.

♪♪ ♪♪ These woodlands are her domain... the treetops her lookout and her pantry, where she stores her meals out of reach of thieves like lions and hyenas.

♪♪ Sephiri doesn't tolerate any other female leopards here.

With one exception...

Her 2-year-old daughter, who was supposed to leave home months ago.

She shares her mother's appetite for impala antelope.

And although by now this freeloader is old enough to hunt them for herself... ...why bother when you can just raid your mother's pantry?

Her strategy is this.

whenever Sephiri leaves a kill, she shows up and helps herself.

♪♪ While the forest is their sanctuary, Sephiri is always alert to the more powerful cats just beyond the tree line.

♪♪ By this age, Molelo's cubs know prey when they see it.

But until they reach two years of age, they won't be able to catch it themselves.

♪♪ That task still falls to Tshaba and her sisters.

♪♪ If you count Molelo, there are 17 bellies to fill.

[ Animal calls ] They're going to need a warehouse of impala.

♪♪ ♪♪ Or one large zebra.

♪♪ ♪♪ Tshaba decides the hunt is on.

♪♪ One of her sisters begins the painstaking stalk.

♪♪ ♪♪ Warthog.

♪♪ Nah, too small.

♪♪ Forget the zebra.

These wildebeest are just the ticket.

♪♪ She makes sure everyone's in place.

Years of hunting as a team means they each know exactly what's expected.

♪♪ She hasn't the speed of a cheetah, nor the forest cover of a leopard.

So the closer, the quieter, the better chance of success.

♪♪ ♪♪ ♪♪ ♪♪ ♪♪ ♪♪ It's a miss for her.

♪♪ ♪♪ ♪♪ ♪♪ But not her sister.

♪♪ ♪♪ The wildebeest will feed the whole family for a day.

♪♪ Close by, the world is quietly changing.

Rainfall from far upstream is making its way down the Gomoti, stealthily creeping over its banks and across the parched plains.

[ Birds chirping ] ♪♪ As the water spreads, so will its influence on the cats' world.

♪♪ [ Birds squawking ] In Sephiri's dry woodlands, winter winds gust through the trees, stripping them bare.

The sight of Sephiri has squirrels hot under the collar.

[ Squirrel squeaking ] She's been so secretive that weeks have passed before the world realizes she's no longer pregnant.

♪♪ ♪♪ It's another daughter.

♪♪ There should be a second one somewhere.

♪♪ She's on her way.

♪♪ Something's not right.

♪♪ It's Sephiri's older daughter.

♪♪ And she has the cub in her sights.

Female leopards are known to kill the cubs of others.

She can't outrun an adult.

♪♪ ♪♪ ♪♪ But she can hide.

♪♪ ♪♪ ♪♪ ♪♪ [ Leopard growling ] For some reason, the cub has broken cover.

♪♪ And now they've caught their mother's attention.

♪♪ ♪♪ Sephiri takes charge.

There'll be no violence here today.

But it's time for change.

♪♪ Her daughter protests, but she must leave.

♪♪ There's not enough space in this small world for them all.

♪♪ ♪♪ Sephiri watches her go to find another woodland to call home.

Her cubs have been born into a dangerous, crowded world.

They're going to need her full attention to get through these first vulnerable months.

♪♪ Until they learn to stay hidden and master their woodland home, they are at risk.

♪♪ Over the weeks, the waters spread across the world, swallowing large parts of the plains.

[ Water splashing ] The flood brings company.

Buffalo.

Mega-herds pour across the Gomoti and into the cats' world.

[ Buffalo lowing ] They've left winter's dry pastures behind for the lush grazing sprouting through the floodwaters.

♪♪ And following them... is trouble.

Two drifters on the verge of adulthood, kicked out of their birth pride.

Now, their territory is wherever the buffalo roam.

Although they have the power to take down adults, there's almost always an easier option.

♪♪ ♪♪ Male lions have little patience for prolonged stalking.

♪♪ ♪♪ ♪♪ ♪♪ The herd won't give up one of its own without a fight.

♪♪ ♪♪ But the brothers know that if they can ride out the buffaloes' fury, the calf is theirs.

♪♪ ♪♪ ♪♪ ♪♪ ♪♪ The lowing of buffalo is music to the ears of Tshaba and her pride.

[ Buffalo lowing ] These herds could keep them fed all through winter.

It's an irresistible, dangerous lure for the mothers.

Close by, Tharo and his siblings can't catch a break.

Buffalo are too big for them to hunt, and they've crowded out most of their impala prey.

♪♪ ♪♪ Worse than that, their hunting grounds are underwater.

♪♪ ♪♪ Even if they found prey, they can't chase anything through this.

♪♪ ♪♪ ♪♪ Now, with new lions moving in, the small world has become a whole lot smaller.

♪♪ If they want to eat, they can't stay in these plains.

They must find prey and dry land.

♪♪ [ Birds chirping ] With large parts of the plains flooded, impala have drifted to the higher ground of Sephiri's woodland.

♪♪ Since the rut months ago, the pregnant ewes have been eating for two.

It could be a super-sized meal for Sephiri right on her doorstep.

As long as she remains unseen.

No, now is not a good time to play.

♪♪ Sephiri's an ambush predator, a silent assassin working alone.

♪♪ Except today, she has an intern.

♪♪ ♪♪ Her cub must sit out this next part.

It's adult's work.

♪♪ ♪♪ To watch Sephiri hunt, is a masterclass in stealth.

Effortlessly, she closes the gap.

The precision placement of each footstep calculated for maximum silence.

♪♪ Surprise!

♪♪ ♪♪ With these two around, hunting is impossible.

♪♪ ♪♪ ♪♪ If she's ever going to feed herself and them, she'll have to leave them on their own.

It's not ideal.

In her absence, anything could go wrong.

♪♪ ♪♪ [ Birds chirping ] Along the river, the buffalo herds are a magnet to life.

[ Buffalo lowing ] Their leisurely pace suits cattle egrets looking for a perch and a snack.

Buffalo meat is a powerful addiction for lions, and in the passing weeks, it's enticed more homeless young males into the world.

[ Lion grunting ] They scrap among themselves over the spoils... ...and begin to earn their battle scars.

They'd better hope Molelo doesn't catch them.

Right now, his full attention is on a buffalo of his own.

And he's not sharing any of it.

Even though he's stuffed.

♪♪ Across the river, Tshaba and her pride are after the same dangerous high.

♪♪ ♪♪ With adult buffalo, the outcome is never certain.

And always in the thick of it, these young trespassers, looking for an easy meal.

♪♪ ♪♪ As long as these other lions are here, the river is no place for the pride.

♪♪ ♪♪ The mothers must always balance prized prey against their cubs' safety.

♪♪ ♪♪ [ Animals calling ] From the beginning of time in this small world, impala have looked to baboons for security.

From their watchtowers, the primates call out threats to the earthbound impala.

With their own infants to protect, baboons are the eyes and ears of the woodlands.

And Sephiri's mortal enemies.

So whenever they're around, she specializes in vanishing.

And she's passed on the skill.

Meanwhile, the cheetahs have followed the impala to the edge of Sephiri's woodland.

♪♪ ♪♪ The baboons are all on the ground and haven't seen them yet.

♪♪ Their mother taught them that it is not smart to hunt near baboons.

Tharo's forgotten that lesson.

♪♪ ♪♪ ♪♪ ♪♪ Male baboons will stop at nothing to protect their troop.

And Tharo's had a lucky escape.

♪♪ As long as the all-seeing baboons live in the woodlands, the siblings will have no luck here.

They must keep searching, a quest that will take them beyond the familiar scents of the small world and away from the only home they've ever known.

♪♪ ♪♪ ♪♪ ♪♪ This morning, there's trouble in Molelo's pride.

♪♪ [ Lioness calling ] A cub is missing.

♪♪ One of Tshaba's.

♪♪ [ Lioness grunting ] ♪♪ ♪♪ ♪♪ He's nowhere to be seen or heard.

♪♪ The only thing she can do is retrace her steps from the night before.

♪♪ ♪♪ ♪♪ ♪♪ Somewhere in the chaos of flood and buffalo and gangs of intruders, a small life has been lost.

♪♪ ♪♪ ♪♪ Tshaba calls from dawn to dusk.

But the Gomoti is not giving up its secrets.

[ Lioness calling ] ♪♪ Her hopes fade with the light, and she returns to her pride.

♪♪ ♪♪ ♪♪ Waiting for your mother to come home with breakfast is quite boring.

Left to their own devices, Sephiri's cubs have decided to take themselves on a tour of their woodland home.

♪♪ Their curiosity knows no limits.

♪♪ Nothing to see there.

♪♪ ♪♪ Of all the cubs growing up in this world, Sephiri's are the most precocious, quick to learn basic skills without her supervision.

♪♪ ♪♪ While they have each other for company now, unlike lion sisters, they're each destined for a life on their own.

♪♪ [ Impala barks ] Without her cubs as baggage, Sephiri has secured a meal.

[ Flies buzzing ] As she drags the carcass to where she left them, she's leaving a trail.

♪♪ ♪♪ ♪♪ Now, to find her cubs.

They should be close by.

But they're not.

♪♪ ♪♪ ♪♪ ♪♪ ♪♪ ♪♪ They've both managed to stay out of trouble.

♪♪ ♪♪ An inquisitive hyena is following the carcass's trail.

Even young hyenas like this are a threat to the cubs.

♪♪ [ Leopard snarls, hyena whimpering ] Not on Sephiri's watch.

♪♪ Her cubs might be growing more independent, but Sephiri still needs to take care of the serious stuff.

♪♪ They must get back to the carcass before other thieves arrive.

♪♪ [ Buffalo lowing ] As winter passes by, the flood moves on downstream, taking the buffalo and young lions with it.

But not all of them.

It's the calf killers.

♪♪ They've reached the age where they want what Molelo has -- land and a pride to call their own.

♪♪ They've had a good time in his world.

Now they're marking it out as theirs.

♪♪ Molelo's on patrol.

Bulked up by buffalo season, he's got a new lease on life.

♪♪ ♪♪ The stink of outsiders.

♪♪ That's a threat to his family.

♪♪ He must hunt them down and evict them.

♪♪ They've heard the roar of a lone male here.

There are two of them.

They're ready to take him on.

♪♪ ♪♪ Molelo doesn't know what he's up against, but that's never stopped him.

♪♪ He's hot on their trail now.

♪♪ ♪♪ ♪♪ Their moment has arrived.

♪♪ So, this is the beast behind the lone voice.

And he's frightening.

♪♪ [ Lion grunting ] ♪♪ They're not in Molelo's league...yet.

He makes sure they don't forget it.

♪♪ [ Lions growling ] ♪♪ Far beyond the reach of Molelo's roars, a young cheetah cleans up after a meal.

♪♪ ♪♪ After a long journey up the Gomoti shoreline, Tharo and his siblings have reached a new land.

♪♪ [ Lion calling ] ♪♪ ♪♪ There are lions here too.

But that will be the case wherever they go.

♪♪ Together, they've learnt to navigate a landscape filled with more powerful cats.

♪♪ A few months from now, they'll each go their separate ways... ...to settle new small worlds of their own.

♪♪ [ Thunder rumbles ] ♪♪ ♪♪ By the time the summer rains return, Sephiri has seen her cubs through their most vulnerable months.

♪♪ The wet season means new life... ...and easy pickings to satisfy her cubs' growing appetites.

♪♪ ♪♪ But Sephiri's journey is far from over.

She'll still have to guard and guide them through another winter before she sends them off into the world beyond.

♪♪ ♪♪ Fifteen months have passed since Molelo became a father.

And he's delivered.

♪♪ ♪♪ His exhausting patrols have kept his cubs safe, and now they're old enough to avoid danger on their own.

His days as the top cat in this world are numbered.

♪♪ But he has sons who will carry his blood into new worlds... ...and daughters who will remain and strengthen the pride.

♪♪ Alongside Tshaba and her sisters, they'll continue to roam this small world and one day raise cubs of their own on the shores of the Gomoti.

♪♪ ♪♪ ♪♪ ♪♪ ♪♪ To learn more about what you've seen on this "Nature" program, visit pbs.org.

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