Horizon - The Day the Earth Nearly Died (2002)

250 million years, long before dinosaurs roamed the earth, the earth and the oceans teemed with life. This was the Permian, a golden era of biodiversity that was about to come crashing to an end. Within a few thousand years, 95% of life on the planet would be destroyed, Earth’s biggest mass extinction has ever known. What natural disaster could kill such a massive scale? Only in recent years the truth has begun to emerge from the rocks in Antarctica, Siberia and Greenland.