Zoologist Nigel Marven explores the wildlife of the Canadian Arctic. It is springtime and Nigel starts his nine-month quest to explore the realm of the polar bear. He takes a dogsled ride from Churchill to see Arctic foxes and caribou; braves temperatures of -30 degrees to witness the jaw-dropping majesty of the Northern Lights at Wapusk National Park; and follows a polar bear mother and two cubs across the tundra.

Zoologist Nigel Marven explores the wildlife of the Canadian Arctic. Nigel returns to Churchill where the Arctic foxes have had nine tiny cubs, and beluga whales have appeared in the river. The first polar bears of summer are also arriving and Nigel is delighted to encounter one swimming at sea. With the weather getting ever warmer, he is able to venture further north and visits Cambridge Bay, where he witnesses a breathtaking wolf attack on a herd of musk oxen.

Zoologist Nigel Marven explores the wildlife of the Canadian Arctic. Summer arrives in the Inuit community of Igloolik in the far north of the country, where Nigel watches bowhead whales and dives from an iceberg to swim with walruses. In Churchill, he catches up with the nine fox cubs; attempts to catch a speeding lemming; and dives with beluga whales in the freezing river. In the boreal forest to the south, great the grey owl chicks are climbing the trees.

Zoologist Nigel Marven explores the wildlife of the Canadian Arctic. Nigel witnesses a flurry of polar bear activity in Igloolik as the predators wait patiently for some walrus to show up. In the south, more bears patrol Churchill town, waiting for Hudson Bay to freeze over so they can hunt at sea. Nigel uses a 'tundra buggy' to get around, as large males play-fight in the middle of a snowstorm.