Cosmos: A SpaceTime Odyssey: Season 2, Episode 12

2 - 12: The World Set Free

Our journey begins with a trip to another world and time, an idyllic beach during the last perfect day on the planet Venus, right before a runaway greenhouse effect wreaks havoc on the planet, boiling the oceans and turning the skies a sickening yellow. We then trace the surprisingly lengthy history of our awareness of global warming and alternative energy sources, taking the Ship of the Imagination to intervene at some critical points in time.