"I'm flying over the Great Rift Valley in East Africa." "And below me is a landscape in turmoil, torn apart by the twisting and buckling of the Earth's crust." "It's also a landscape of huge and unpredictable change that forces animals day by day, season by season, to gamble with their lives." "But for those who win, this is one of the most fertile landscapes on Earth." "Nyiragongo, the largest lava lake in the world." "Bubbling up from nearly 10 miles beneath the surface." "Nowhere takes you closer to the fiery heart of the planet." "Mount Nyiragongo is one of the most active volcanoes in Africa." "Its eruptions can be seen from space." "As magma churns below the Earth's crust, the land to the east of here is being torn apart." "Volcanoes like this are continually changing the face of Eastern Africa." "The volcanoes here may have a violent side, but life flows from these infernos." "Fertile ash from countless eruptions carpets the land, creating the ideal conditions for grasses to flourish on an immense scale." "And with the grasses, come animals in numbers found nowhere else on Earth." "Wildebeest." "Nothing stands in their way." "All this just to reach fresh grass." "The ever-travelling herds are only one element of life here." "Look closer and there are new stories to tell." "Living on the savannah is about making most of the hand the landscape deals you." "But here it's always a gamble." "Everything may change tomorrow." "From their vantage point, agama lizards wait for the arrival of the herds, ready to seize their moment." "It's pay day." "Over a million wildebeest on their doorstep." "And with the wildebeest come flying insects." "Billions of them." "Food, if only they could catch them." "Time for a rethink." "This agama lizard has spotted an opportunity." "Only one thing attracts more flies than the wildebeest." "Lions that have eaten wildebeest." "Lions are famously-bad tempered." "They could swat the lizard like the flies he's hoping to ambush." "He will need to pick his target carefully." "Not her." "Or her." "Maybe." "But no." "To be within striking distance, he's got to hold his nerve." "Got one." "Now, he's getting his eye in." "But this might be a bit ambitious." "It may take courage to hunt on the back of a lion." "But it takes sense to know when to run away." "The wildebeest won't stay for long." "And when they leave, most of the flies will follow." "Change is everywhere in East Africa." "This grassland was once covered by a forest that ran unbroken from west coast to east coast." "Today, high above the plains, swirling clouds hide mountains that tower three miles into the sky." "These frozen summits now form part of a mountainous barrier separating the ancient jungles in the west from the savannahs of the east." "Up here lies the largest glacier in Africa, just a few miles north of the equator." "These are the legendary Mountains of the Moon." "The height of these peaks means they create their own weather." "The local name for these mountains is Ruwenzori, "the rainmaker."" "Meltwater flows down from the glaciers." "And on the lower slopes, all this water supports thick jungle." "Remnants of the dense, steamy forests that once dominated the whole of East Africa." "But driven by a drying climate beyond the mountains, the forests began to wither away." "Today, only small pockets of upland jungle remain, home to animals who once roamed the ancient forests." "The largest living primates on Earth." "Mountain gorillas." "This little one's ancestors have lived in forests like these for millions of years." "But all around, the world has changed to swamp and savannah." "This is the furthest these mighty giants now venture into Eastern Africa." "They're marooned on their islands in the African sky." "Below the highlands, vast wetlands cut swathes through the open savannah." "Bangweulu Swamp is huge." "Its name means "where the water meets the sky."" "Hidden amongst this maze of waterways is a creature like no other." "A giant prehistoric-looking bird." "A shoebill." "Standing well over a metre tall, she roams these swamps" "trying to catch catfish." "Not exactly what she was after." "Deeper into the swamp lies the reason for all this fishing." "This chick is just three weeks old, and a little bit wobbly on its feet." "Its vast bill means it has trouble balancing." "It won't be able to fly or even walk properly for several weeks." "It's entirely reliant on its parents for food and water." "There is also a smaller chick, who isn't doing so well." "The larger chick pesters its mother for a drink." "While she goes off to fetch water, it reveals a dark side to the relationship with its nest mate." "It's three days older than the other chick and has always won the race for food and attention." "This is more than just a scrap between two siblings." "As the mother returns, she sees what the larger chick has done." "The smaller chick seeks its mother's comfort." "But she has already made her choice." "Only her first born will get to drink." "Shoebills very rarely raise more than one chick." "The younger chick was only ever an insurance, in case the elder didn't make it." "Now it's old enough, the adults know that they're better off putting all their efforts into bringing up just one fit and healthy youngster." "The swamps changing water levels mean fishing is too unpredictable for them to gamble on trying to raise two chicks." "Nothing here stays the same for long." "This is the time of year when Eastern Africa is beginning to dry." "The rivers and waterholes are shrinking." "The land continues to dry out." "Tensions rise." "Hippos seek what relief they can." "This time of relentless drying is also when another force of change ravages the land." "Without warning, fires rip through these tinder-dry plains." "The flames sweep across the savannah at 50 miles an hour, reaching temperatures of nearly 7, 000 degrees, consuming everything in their path." "Each year, an area larger than Britain goes up in smoke." "But this destruction can bring opportunity, if you're prepared to take a risk." "Drongos, bee-eaters and rollers bravely pluck fleeing insects from amongst the flames." "There's little better than a char-grilled grasshopper." "These fires may appear devastating but they are, in fact, part of a natural cycle that is essential for the regeneration of East Africa's grasslands." "But sometimes the cycle is broken, just when a change is most needed." "Here, on the plains of Amboseli, in the shadow of Mount Kilimanjaro, the seasonal rains have failed for the last two years." "And this year, they are already long overdue." "It's the hardest drought for half a century." "Amboseli is usually a haven for elephants." "These plains should be green and covered with grass." "Now, there is nothing but dust." "This family is forced to travel constantly, searching for anything they can eat." "The young must keep up." "Sometimes, there's not even time to suckle." "With the grass gone, all the elephants can scratch from the dust is withered twigs." "The adults might just survive on this, but it will not support a calf for long." "Every mother in the herd is struggling to provide milk for her calf." "The search for food is increasingly urgent." "As the herd moves on, this female faces a terrible choice." "To carry on with her family or stay behind with her calf, who's becoming too weak to even stand." "They will soon be out of sight." "But her instinct is to stay." "She won't abandon her baby." "With the calf's last breath, she knows that her battle is lost." "There are places even more hostile than the dust-choked plains." "These alien landscapes are actually the sunbaked salt crusts of a chain of lakes that run through East Africa." "The face of these soda lakes changes day by day as the sun evaporates the water, leaving the salts behind." "The waters here are toxic, poisoned by volcanic springs." "But life does exist, even here." "The strange colours are created by algae specially adapted to live in this corrosive liquid." "And it is these algae that attract one of the most astonishing animals found in East Africa." "Among the steaming geysers of Lake Bogoria, over a million Lesser flamingos bathe and feed in the caustic water." "They gather whenever the algae bloom." "These huge numbers create one of the greatest wildlife spectacles on Earth." "Almost all the world's Lesser flamingos live on this chain of lakes, moving from one lake to another as the amount of algae in each changes." "All along the lake shore, volcanic vents are a reminder of the forces that continue to change this land." "And a streak of colour on the horizon signals that relief for the parched plains is on its way." "At last, countless storms drench the thirsty ground." "Rain changes everything yet again." "A crowned eagle has been desperately waiting for what she hopes the rain will bring." "Food for her hungry chick." "Nesting here has been her biggest gamble." "A chick's life depends on the arrival of creatures from the far rainforests of the Congo." "Her wait will soon be over." "The largest mammal migration in Africa is on the move." "10 million fruit bats are drawn to this tiny forest on the edge of the eastern savannah." "The bats flock here to gorge themselves on fruit." "It's what the crowned eagle and her chick have been waiting for." "But they're not alone." "Other eagles have flown in from miles around." "Fish eagles, martial eagles, and they're all after the bats." "The gamble the crowned eagle took months ago by nesting here has paid off." "She is the only eagle to actually nest in this forest." "The only one who took the risk to breed here well before the trees came into fruit and the bats flooded in." "She only breeds once every two years, so her timing must be perfect." "In a few months, the bats will leave, but her gamble means her chick will have the best possible start in life." "These grasslands have been grazed and burned and have endured the harshest drought in generations." "But with the rains, they're beginning to recover." "And on the once dust-choked plains of Amboseli there is a return to the good times." "The drought here killed hundreds of elephants, but the survivors are now returning home." "And with them, there's a surprise." "A newborn." "Surrounded by food, the youngster can concentrate on more important things." "Like chasing egrets." "The bulls also return." "This bull has waited many years for his chance to father the next generation." "Now, he must fight his way to the top." "But his rival is massive." "Each of their heads weighs as much as a car." "They have been duelling for days." "Now, in its third day, the contest is reaching a climax." "Soon, one will be forced to concede." "The power of these clashes can even shatter tusks." "Three days of battle is at an end." "The victor has won the right to the females." "The process to replace what the drought took away has begun." "Soon, the elephants will be at full strength again." "Every day the animals of Eastern Africa gamble with their lives." "But despite the continual changes they face, their extraordinary adaptability just tips the odds of survival in their favour." "East Africa may seem very cruel, but there's nowhere else that provides such rich opportunities for those that are prepared to take them." "And in the end, it was these ever-changing savannahs that produced the most adaptable species of all, ourselves." "Filming in East Africa would take the team on both a physical and emotional journey through the extremes of this landscape." "These are the legendary Mountains of the Moon, towering over 5, 000 metres into the African sky." "Just miles from the Equator, they're the highest mountain range on the continent and home to the largest glacier in Africa." "To reach the summit, the team had to travel on foot, the same way as climbers did when they first reached the top just over 100 years ago." "It would take more than two weeks, climbing over 3, 000 metres from the valleys below." "Six days into their trek, still well below the summits, the team come to realise why Ruwenzori, the mountains' other name, means "the rainmakers"." "Just after we set off it started raining, then it started hailing, um, and the idea had been that we'd stop here for an hour or two and do some shots, but as you can probably see," "there's not a great deal of view." "Brilliant shots of rain and hail and fog." "Beyond that, we're pretty stuffed." "So, it's becoming a bit of a theme." "For the crew and over 75 guides and helpers, it's hard going carrying nearly a ton of kit through the marshy valleys." "Mud." "Mud." "There's a little bit more mud." "But it's not just the bogs they have to deal with." "There was a fairly small but slightly disconcerting earthquake last night, so, let's hope we don't get any of those below any rocks." "The team continue to climb and before long, the rain turns to snow." "They eventually arrive at the highest hut, surrounded by ice and nearly three miles up." "This will be base camp for the crew." "We've got a kitchen over there." "Um, over there down a really treacherous precipice is the toilet, which is just a shack with a big hole in the floor." "From here, they'll make the hardest part of the ascent right up to the glaciers." "Well, this is, believe it or not, one of the better viewpoints." "So we're gonna hang around here for a little while, to wait till the fog clears." "But the weather isn't on their side." "So much for hoping the weather was going to get better." "All that optimism now seems completely ill-founded." "With the storm clouds closing in, the team are forced to retreat." "This enormous weather front's come in, as is entirely unusual." "We were just coming down as the thunder bursts around us." "So just trying to get back and go and get inside the hut and hopefully weather it out." "After days of climbing and finding the peaks hidden by fog, filming the summits is looking increasingly impossible." "It can be pretty frustrating at times." "The group of, maybe, 70 people that we've involved with doing this directly and you get all the way up here and then, and then we can't film anything because of the weather." "So, it is just a matter of sitting it out and waiting." "And you have to sort of hope that things come right in the end." "The rainmakers are certainly living up to their name." "But by complete contrast, other parts of East Africa were gripped by drought." "At the beginning of the production, Mark Deeble travelled to Amboseli, just a few hundred miles from the Ruwenzoris, to film the plight of the animals there." "Well, I've never seen anything quite as bad as that drought." "When we talked to some of the Maasai elders, they said it was the worst drought they'd seen in 50 years." "Amboseli is famous for its huge herds of elephant, but the drought had dispersed them far and wide." "Those that remained were struggling to find what little food was left." "When we first saw the group, we could tell instantly that they..." "They were in a really serious condition." "They were thin and obviously starving." "Mark knew that many of the calves would not survive." "Although desperately painful to witness, nothing would convey the cruel power of the drought more than this mother's struggle to keep her baby alive." "The thing about filming a situation like that, you know, when an elephant calf dies, is that when you're actually filming it you're so caught up in the moment." "But it was only after filming, when I put the camera away and I looked there and there was this dead calf and the mother standing there, grieving, that the full impact of what I'd just filmed hit me." "People often say to me, you know," ""Could you not have intervened in a situation like that?"" "There are times when you can help." "But in that time in Kenya there was no food available." "Now, you have to also consider the mother." "If we'd gone in there and tried to take the calf away, it would've been absolute mayhem." "She'd have got incredibly stressed and that would probably have jeopardised her survival." "In that particular situation, when everything around us was dying, there was absolutely nothing we could do to help that young elephant." "Although too late to save the calf, a few months later, the rains did finally return." "When we returned it was amazing." "It was lush and green again." "And the elephants, in the rains, they all tend to come together." "So it was like all of these groups which had been dispersed, which had been just somehow coping on their own, all got back together again." "It was almost a sort of festival type atmosphere." "That was when, essentially, they come together, they mate, and then after that lots of young calves being born." "Since the end of the drought, over 220 calves have been born in Amboseli, and that number is still rising." "It's the biggest elephant baby boom on record." "I think what's lovely to see in that situation is that, having..." "Having been through such a terrible drought, to see the way in which, you know, if you let things alone they do have incredible capacity to bounce back." "Back in the mountains, and several failed ascents later, the team were still battling through the white-out." "They try one last time." "There's cloud below us and cloud above us." "It somehow seems slightly, like we're heading nowhere, slowly." "Then, as they reach the top, finally the clouds begin to part." "It's absolute magic here." "We've just come through the densest, densest cloud, having absolutely no idea what's surrounding us." "The past few days have just been rain and cloud and rain and cloud." "And, as if by magic, there's the most spectacular view of ice and glaciers and mountains that you just wouldn't think was on the Equator." "It's just amazing." "It's the most spectacular mountain scenery I've seen." "And to think it's in Africa is just mind-boggling." "These mysterious mountains have finally unveiled their secrets." "And on the plains beyond, the elephants have returned to their home." "Despite having been explored by filmmakers for over a century," "East Africa still has the power to enchant and surprise us all."