A new force threatens our perfect planet. In the past, five mass extinction events were caused by cataclysmic volcanic eruptions. It was not the lava or ash that wiped out life, but an invisible gas released by volcanoes: carbon dioxide. Almost every part of modern life depends on energy created by burning fossil fuels, and this produces CO2 in huge amounts. Humans are changing our planet so rapidly, it’s affecting earth’s life support systems: our weather, our oceans and the living world. The greatest change to be made is in how we create energy, and the planet is brimming with natural power that can help us do just that. It’s these forces of nature - the wind, the sun, waves and geothermal energy - that hold the key to our future.
Through compelling animal-led stories and expert interviews, we discover how CO2 is destabilising our planet. We meet rescued orphaned elephants in Kenya, victims of ever worsening droughts, and join ocean patrols off the coast of Gabon fighting to save endangered sharks. In the Amazon, we witness wildlife teams saving animals in the shrinking forests, and in San Diego we enter a cryogenic zoo preserving the DNA of endangered species before they become extinct.

The mission of NASA's Osiris-Rex is to intercept a giant space rock and crack the mysteries of a potential killer asteroid. Can it unlock how asteroids kick-start life on Earth and reveal why they might be our ticket to other worlds? To find out, we take a ride with one of NASA's most ambitious missions to investigate a space rock in more detail than ever before, to reveal how asteroids will rewrite the past and forge the future of our solar system.

Brian Cox looks at our attempts to answer one of the most profound questions we can ask – are we alone in the universe? With scientists sending space probes to the furthest reaches of our solar system and beyond, the scientific search for alien life has begun. Inspired by a childhood love of science fiction, Brian still hopes to hear from ET. In this film, he explains why this search deserves to be taken seriously, and he explores the chances of it happening.

Jeremy Clarkson decides to become a naturalist. 'In just 30 years, insect numbers have dropped by 25% and they're still falling. Without insects, all life on Earth ends. Everywhere where insects like to live is disappearing and I've decided to do something about that. My plan is to make my hedgerows, my valleys, my woods, and my streams more attractive to creepy crawlies. In essence, I am going to leave chunks of the farm completely alone. I'm going to put Mother Nature in the driving seat. It's a process called wilding.'

In the Taurus Mountains Simon stays with descendants of the original Turks, nomads known as Yoruks, whose lifestyle is under threat from the modern world and an increasingly religious government. They're not the only minority at odds with the authorities in Turkey; Simon sees first-hand the devastating effects of fighting in the country's Kurdish region. In an area where the government has detained foreign journalists, Simon gathers unique footage in the aftermath of a crackdown on Kurdish militants - the wholesale destruction of the historic centre of one of Turkey's oldest cities.
Away from the conflict in the south, Simon heads towards the Black Sea coast. He meets a wildlife conservationist protecting Turkey's population of brown bears, and villagers who still communicate over long distances using an ancient bird language. In the country's capital he meets a victim of President Erdogan's authoritarian purge of people accused of complicity in the failed coup against him.
Finally Simon's journey comes full circle when he returns to Istanbul - home to the new craze of 'Ottomania', a celebration of the vast empire that preceded modern Turkey. Simon visits the set of one of the world's most popular TV dramas - even getting a speaking role - based in the court of an Ottoman sultan

To survive Mars, our species will need to evolve how we eat, drink, and build our homes. Will we need our genes to evolve as well? Sometime in the future humans will leave Earth to colonize Mars, and in doing so will begin to adapt to life on another planet in surprising ways. Evolutionary biologist Dr. Scott Solomon foresees a series of changes to our species from the size of our hearts and heads to the pigments in our skin.