Off Australia's northeast coast lies a wonder of the world, a living structure so big it can be seen from space, more intricate and complex than any city, and so diverse it hosts a third of all fish species in Australia. The Great Barrier Reef as we know it -- 8,000 years old and home to thousands of marine species -- is dying in our lifetime.
As spring lights up the land, Alaska faces one of the greatest transformations on earth. Temperatures soar, and as the sun's rays hit the snow and ice, water, light and warmth return. Alaska's transition to spring may look magical, but for those animals emerging from a long winter's sleep, it's a time of intense competition, as everything is in a rush to cash in on Alaska's riches.
Six months after the explosions at the Fukushima nuclear plant and the release of radiation there, Professor Jim Al-Khalili sets out to discover whether nuclear power is safe. He begins in Japan, where he meets some of the tens of thousands of people who have been evacuated from the exclusion zone. He travels to an abandoned village just outside the zone to witness a nuclear clean-up operation.