Sub Zero

S1, E4: It's hard to imagine a more inhospitable environment than the sub-freezing temperatures of the arctic regions. Yet humans have lived, explored, and worked here for centuries. What does it take to engineer a massive plane that can carry cargo to and from the polar region? How can the next generation of super Ice Breakers provide a lifeline in places even aircraft can't reach easily? What secret ingredients go into the rarely seen but incredibly critical rotary snow plough to ensure trains don't derail in icy regions? And meet two wonderfully versatile all-terrain vehicles that can move through snow where everything else sinks to a halt. With climate shifting and resources critical in remote frozen areas, these cool machines are truly game changers.