When the Earth first formed from clouds of dust and gas 4.6 billion years ago, it was - like so many other lifeless worlds in the universe - devoid of an atmosphere, an inhospitable rock floating in the black void of space. But as the young planet is pummelled by asteroids, a period of extraordinary upheaval begins.

Chris Packham tells the miraculous story of how plant life turned the Earth from a barren rock into a vibrant green world - a 4.5-billion year-saga of extraordinary highs and lows that almost wiped out all life on the planet. The Earth began as a water world without land masses. Then, a giant asteroid bombardment triggered its plate tectonics, leading to huge fungi, soil and giant swamp forests. But the early plants locked so much carbon dioxide that global temperatures suddenly plunged.

Earth’s terrifying journey into the deep freeze started with fire, not ice. 800 million years ago, long before the age of the dinosaurs, indeed any animal life, the giant supercontinent Rodinia broke up. Earth’s vast powerful tectonic forces ripped the land apart, kicking off a series of events that resulted in huge amounts of carbon dioxide being sucked from the atmosphere and sending global temperatures plummeting.

Chris Packham explores one of the darkest periods in Earth’s history: the worst mass extinction the planet has ever seen, when as much as 90% of all species died 252 million years ago. This extraordinary moment in Earth’s history took life to the brink, wreaking havoc and destruction on an unprecedented scale. But, somehow, life found a way to bounce back, and a new geological era ushered in the age of the dinosaurs.