As the world warms, the threat from rising sea levels poses an alarming potential for disaster. Some models now project a one-meter sea level rise over the next century, which could displace millions of people, from Florida to Bangladesh, and require trillions of dollars’ investment in coastal infrastructure. But these models don’t reflect recent findings that glaciers in Greenland and Antarctica are melting at an ever faster rate. What explains this alarming acceleration, and just how can we figure out what’s happening inside a gigantic wall of ice? In collaboration with National Geographic, NOVA follows the exploits of acclaimed photojournalist James Balog and a scientific team as they deploy time-lapse cameras in risky, remote locations in the Arctic, Alaska and the Alps. Their goal is to create a unique photo archive of melting glaciers that could provide a key to understanding their runaway behavior. They’re grappling with blizzards, fickle technology and perilous climbs up craggy precipices to anchor cameras that must withstand sub-zero temperatures and winds up to 170 mph. In this high-action adventure, NOVA investigates the mystery of the mighty ice sheets that will affect the fate of coastlines around the world.