Our journey begins with David Attenborough at the North Pole, as the sun returns after six months of darkness. We follow a pair of courting polar bears, which reveal a surprisingly tender side. Next stop is the giant Greenland ice cap, where waterfalls plunge into the heart of the ice and a colossal iceberg carves into the sea. Humpback whales join the largest gathering of seabirds on earth to feast in rich Alaskan waters. Further south, the tree line marks the start of the Taiga forest, containing one third of all trees on earth. Here, 25 of the world's largest wolves take on formidable bison prey. At the other end of our planet, the Antarctic begins in the Southern Ocean where surfing penguins struggle to escape a hungry sea-lion and teams of orcas create giant waves to wash seals from ice floes -a filming first. Diving below the ice, we discover prehistoric giants, including terrifying sea spiders and woodlice the size of dinner plates. Above ground, crystal caverns ring the summit of Erebus, the most southerly volcano on earth. From here we retrace the routes of early explorers across the formidable Antarctic ice-cap - the largest expanse of ice on our planet. Finally, we rejoin David at the South Pole, exactly one hundred years after Amundsen then Scott were the first humans to stand there

Enjoy this wonderful documentary from Disney Nature about a family of brown bears living in the coastal mountain ranges of Alaska." A brown bear mother named Sky gives birth to two cubs named Amber and Scout in her den on a mountain slope. When April comes the bears will be ready to leave the den. As the bears leave the oncoming summer brings with it a threat of avalanches. Fortunately the bears are able to avoid disaster. Upon reaching the lush valley below, the cubs meet the other bears, some of which pose a threat to the cubs; among these bears are Magnus, a big healthy male, and Chinook, an older male. The family works together to survive the spring, with Sky keeping the cubs safe from Tikaani, a pesky grey wolf...