In this series Professor Iain Stewart tells a stunning new story about our planet. He reveals how the greatest changes to the Earth have been driven, above all, by plants. In this first episode Iain journeys from the spectacular caves of Vietnam to the remote deserts of Africa. He sees how plants first harnessed light from the sun and created our life-giving atmosphere. He uncovers the epic battle between the dinosaurs and the tallest trees on the planet. And, using remarkable imagery, he shows plants breathing - and for the first time talking to each other.

This episode is centered around how science, in particular the work of Clair Patterson (voiced in animated sequences by Richard Gere[33]) in the middle of the 20th century, has been able to determine the age of the Earth. Tyson first describes how the Earth was formed from the coalescence of matter some millions of years after the formation of the Sun, and while scientists can examine the formations in rock stratum to date some geological events, these can only trace back millions of years. Instead, scientists have used the debris from meteor impacts, such as the Meteor Crater in Arizona, knowing that the material from such meteors coming from the asteroid belt would have been made at the same time as the Earth. Patterson also examined the levels of lead in the common environment and in deeper parts of the oceans and Antarctic ice, showing that lead had only been brought to the surface in recent times. He would discover that the higher levels of lead were from the use of tetraethyllead in leaded gasoline resulting in government-mandated restrictions on the use of lead.

An exploration of active volcanoes in Indonesia, Iceland, North Korea and Ethiopia, Herzog follows volcanologist and co-director Clive Oppenheimer, who hopes to minimize the volcanoes’ destructive impact. What is the Herzog’s quest? To gain an image of our origins and nature as a species. He finds that the volcano—mysterious, violent, and rapturously beautiful—instructs us that, "there is no single one that is not connected to a belief system".

The series highlights the major events which have shaped the Earth's history and allowed life to flourish. Follow Dr Stewart's personal journey to some of the most remote places on the planet. The atmosphere is Earth’s protective layer, cloaking us in a warm, oxygen-rich embrace and shielding us from the cold hostility of space. It acts as a natural greenhouse, keeping the Earth 51 degrees Fahrenheit warmer than it would otherwise be. Yet the atmosphere is also full of contradictions. It’s immensely powerful but at the same time highly sensitive. It’s destructive, yet it shelters us. It was created in part by the planet’s first organisms, and it continues to be essential for life.

40,000 years ago the steppes of Eurasia were home to our closest human relative, the Neanderthals. Recent genetic and archaeological discoveries have proven that they were not the dim-witted cave dwellers we long thought they were. In fact, they were cultured, technologically savvy and more like us than we ever imagined! So why did they disappear? We accompany scientists on an exciting search for an answer to this question and come to a startling conclusion... A climate change due to a cataclysmic event.

This episode explores the palaeogeography of Earth over millions of years, and its impact on the development of life on the planet. Tyson starts by explaining that the lignin-rich trees evolved in the Carboniferous era about 300 million ago, then explains on the nature of plate tectonics that would shape the landmasses of the world and the asteroid impact that initiated the Cretaceous–Paleogene extinction event, leaving small mammals as the dominate species on earth. Earth's landmasses are expected to change in the future and postulates what may be the next great extinction event.