Dramatic pictures of stunning and unexpected Antarctic scenery lead into an introduction to the area as a whole. The opening program then focuses on the great 'ice machine,' beginning the story of how the ice governs the wildlife that thrives here. Amid vast icebergs in the nutrient rich sea, 650 million tonnes of krill – small shrimp like crustaceans – provide food for numerous species of fish, seals and birds. Krill also attracts whales, and despite the notorious difficulties of filming them, the crew have obtained remarkable footage of these splendid mammals enjoying the bounty.

Spring begins in the sub-Antarctic islands with petrels searching through the snow for their nests. Elephant seals return from the sea and fight for supremacy over their harems, while five million Macaroni penguins battle through the crashing waves of South Georgia to court and breed. Further south the spectacular time-lapse sequences reveal a continent only just being freed from the ice trap. With the aid of remote cameras, there is also rare underwater footage of the hardier penguins as they venture far south to reach their traditional breeding grounds.

During the short Antarctic summer, there is a frantic race to breed. The sub-Antarctic beaches are inundated by noisy, aggressive fur seals, and chinstrap penguins face a daily battle in the hope of successfully rearing a chick. Antarctic terns fly far to find fish for their chicks and Adelie penguins must leave their young in grave danger as they head out to sea.

Autumn, and the ice starts to return. As the first heavy snowfalls bury their young, the birds rush to finish breeding. Penguin chicks gather at the water's edge and following their departing parents and take the icy plunge. Leopard seals burst from the water to grab the unsuspecting fledglings. Storms ravage the continent; the seas begin to freeze over. Beautiful images of frost flowers, diamond dust and other optical effects describe the gradual formation of the ice. Further North, in the Sub-antarctic Islands, fur seal pups are beginning to swim and albatross chicks are fledging.

A season of complete darkness, and the worst weather anywhere on the planet: midwinter in the Antarctic. The hostile landscape seems completely devoid of life, but under the ice – now filmable using new diving techniques and remote video cameras – life abounds. Ghost-like white fish are kept alive by anti-freeze in their blood and giant sea spiders patrol the sea bed. Most astonishing of all are the Weddell seals, the only seal to over-winter so far south, which scrape breathing holes through ice up to two meters thick and hunt as deep as 600 meters to find fish. In the center of the continent, male Emperor penguins huddle for warmth throughout the winter, each incubating a single egg. The hatching of the chicks heralds the approach of spring – the Antarctic year has come full circle.

For humans, too, survival in the Antarctic is a severe challenge. The final program traces the early exploration and exploitation of the continent and its surrounding islands. It also examines the difficulties encountered in the making of the series, and looks at other – more long-term – human activity on the continent: the research stations, the tourists and the attitudes of different countries which claim sections of this vast wilderness. Should its resources be exploited or should Antarctica be preserved as a National Park?