The journey continues into Asia, the world's greatest land mass, in a quest to discover how early hunter-gatherers managed to survive in one of the most inhospitable places on earth - the Arctic region of Northern Siberia. Alice also explores what may have occurred during human migration to produce Chinese physical characteristics, and considers a controversial claim about Chinese evolution: that the Chinese do not share the same African ancestry as other peoples.

Weather controls the distribution of freshwater on Earth. David Attenborough narrates how this uneven distribution has given rise to an incredible diversity of species and habits, from the driest desert to the lushest tropical rainforest. Featuring a colony of ants banding together into a raft every time its home in the Amazon floods, a rain frog that manages to eke out an existence in one of the world's driest habitats on Earth, and the last wild camels that survive the Gobi Desert's bitter winters by eating snow that blows in from Siberia.

The last episode examines the fragile interdependence that exists between forests' wide variety of residents, including bald eagles, hunting dogs and Siberian tigers.
Over half of all the world's trees, evergreen and deciduous, stand in great assemblies. For many of us, they are places of mystery and darkness. They are key to our climate, and home to countless unique species. The boreal forest contains 750 billion trees, and it stores over 40 percent of the world's carbon, making it a vital element in the fight against climate change. In the past, we have destroyed them without hesitation. Yet, forests do have an astonishing ability to recover. If we choose to give forests time and space, they could reclothe the earth with much of the rich and varied communities of animals and plants of which we have, so recently, robbed it. A future with more forests is key to the resilience of our planet.

Nicholas felt enormous pressure to continue the dynasty and expand the empire. He saw his opportunity in the Far East. This brought him into conflict with a rising power, Japan. Russia's disastrous war against Japan prompts civil unrest. The birth of Prince Alexei is incredibly important. He's the long-awaited son that they had hoped so much for. But when Alexei is diagnosed with haemophilia, Siberian mystic Rasputin steps in. He's very good at realizing when something is open that will enable him to increase his power and wealth. The pressure of keeping the secret of Alexei's illness affects the political decisions that Nicky and Alix made for the rest of their reign.

By August 1949 the USSR became the world's second superpower, thanks to its spies who had stolen America's atomic secrets. But by March 1953, Stalin is dead and KGB chief, Beria, is executed later the same year. Nikita Kruschev tries to reduce the power of the security service, splitting it into several sections...but it doesn't last and, soon, the KGB is back.
In the USSR, countless KGB operatives spied on opponents of the regime at home, guarded the state and party leadership, and abroad tried to find out as much as possible about the intentions of the NATO countries and, if possible, to sabotage them.

David Attenborough explores the continent of Europe - a crowded continent transformed by mankind, capturing the challenges and triumphs of its wildlife. The documentary showcases remarkable scenes, from pelicans engaging in coordinated fishing tactics to the resilient Iberian lynx fighting for survival. Amidst Europe's evolving environment shaped by human impact, it emphasizes the importance of protecting wilderness to ensure the future of the continent's precious wildlife.
We will watch surprising encounters with elusive predators like wolves and lynxes living remarkably close to human communities. The documentary offers a unique glimpse into the intricacies of Europe's ecosystems and the delicate balance between its inhabitants and the changing world around them.