Take an amazing journey across Earth's polar regions to explore our least known wildernesses. Northern polar bears and southern penguins both endure unimaginably harsh conditions, while spectacular frozen phenomenon shape life for the planet.

Rejoice with the animal locals as the sun returns from its 5-month absence, bringing warmth and urgency to these icy, windswept worlds. From a 14-year moth pupation to the accelerated rearing of arctic wolves, see life respond to the sun'fs arrival.

It is high summer in the polar regions, and the sun never sets; many species take advantage of the easier conditions, but summer is a tough time for the polar bear family, as their ice world melts away and the cubs take their first swimming lesson.

Autumn means dramatic battles and epic journeys for animals in the polar regions. Time is running out; the Arctic Ocean is freezing over and the sea ice advances around Antarctica every day. Witness riveting behaviours in this transitional season.

Winter is the greatest test for life in the polar regions; in the Arctic, a female polar bear treks into the mountains to give birth; out on the frozen ocean, the entire population of the world's spectacled eider ducks braves the winter.

Meet the nomadic tribes of the north and the residents of the coldest city on earth. See how science continues to bring governments and researchers to both poles. From the clean air to the mineral-rich earth, there is a world of riches to discover.