One man has seen more of the natural world than any other. This unique feature documentary is his witness statement. In his 93 years, David Attenborough has visited every continent on the globe, exploring the wild places of our planet and documenting the living world in all its variety and wonder. Now, for the first time he reflects upon both the defining moments of his lifetime as a naturalist and the devastating changes he has seen. Honest, revealing and urgent, this film is a powerful first-hand account of humanity's impact on nature and a message of hope for future generations.

The Blue Marble is an image of Earth taken on 1972, from a distance of about 18,000 miles from the planet's surface. It was taken by the crew of the Apollo 17 spacecraft on its way to the Moon. Before it was photographed from space, our perspective of Earth was fragmented and disconnected. Recent discoveries have revealed a dynamic and rapidly changing planet, above the crust and below.

Most planets we know of are so hellish, it seems impossible that anything could live. But it's amazing where life can take hold in the Earth. Astrobiologists look for simple single-celled microbes known as extremophiles in places as Danakil Depression, known in Ethiopia as 'The Gateway to Hell.'
In Episode 2, the fictional world is Janus, a planet in such a close orbit than its rotation is locked by the star's gravity and it always shows the same face to its sun. On one side of the planet, it's always daytime, a searing desert. On the other side, it's forever night, a frozen shadowland. Squeezed between the two, a sliver of perpetual twilight. Freezing meltwater flows from the cold side, carving canyons through the landscape. Deep in these canyons lives an extraordinary five-legged creature.

Are rising temperatures driving Earth's ecosystems past a point of no return? We have promising technologies that put solutions within our grasp. Scientists are exploring solutions: from geoengineering to sucking carbon out of the air to cloud brightening, as means to cool the planet. Cutting-edge solutions and high-risk measures. But would they work? And what are the risks of engineering Earth's climate?

In August of 2018, Greta Thunberg, a 15-year-old student in Sweden, starts a school strike for the climate. Her question for adults: if you don't care about her future on earth, why should she care about her future in school? Within months, her strike evolves into a global movement. Greta, a quiet Northern-European girl on the autism spectrum is now a world famous activist. The team behind Greta has been following the young activist from her very first day of school striking. The documentary shows the international crusade of Greta on in her goal to get people to listen to scientists about the world's environmental problems.

David Attenborough takes a stark look at the facts surrounding Climate Change in today's world, detailing the dangers we are already having to deal with and future threats, but also the possibilities for potential solutions to this global threat and the radical political, social and cultural changes needed.
Interviews with some of the world’s leading climate scientists explore recent extreme weather conditions such as unprecedented storms and catastrophic wildfires. They also reveal what dangerous levels of climate change could mean for both human populations and the natural world in the future.