The Big Freeze

S1 E2: Winter comes hard and fast around the Great Lakes, a throwback to the Ice Age that once gripped this region 20,000 years ago. For the many animals that live in and around these vast bodies of water, they must adapt to a world of thickening ice, blankets of snow, and a dome of ultra-cold air called the polar vortex. Enter a world of ice-fishing otters, glowing flying squirrels, singing cod, and other remarkable creatures, all trying to carve out a life in one of the most extreme, unpredictable environments on the planet.