Set against the magical backdrop of the Arctic, NATURE "Snow Bears" is a dramatized story based on the extraordinary adventures and life-changing journey of newborn polar bear cubs as they leave the safety of their den for the first time. Bravely led by their mother, the cubs must make the perilous 400-mile voyage to the sea to feed. Encountering many dangers along the way - Arctic foxes, roaming bears ready to kill, extreme weather, snowdrifts and ice cracks - they undertake an epic survival challenge. These cubs are rarely seen in their natural habitat, and "Snow Bears" is a unique glimpse into their world. Kate Winslet narrates.