Just months after surviving a near-fatal cycling accident, James takes to his bike again, to test the limits of human survival in a race that only a handful of endurance athletes in the world have ever attempted, The Yukon Arctic Ultra. Covering 430 miles of frozen wilderness, he will race through the depths of winter, in minus 50 degrees, battling 50mph freezing winds. Of the athletes taking part, some will race on foot, some on skis, and a tiny number, including James, on two wheels. But the conditions of the trail can vary to such a degree that it's impossible to predict whether a cyclist, skier, or runner will cross the finish line first. To prepare for this ambitious adventure, James has commissioned the building of a new bike, specially designed to withstand the race's punishing terrain. He can take only the lightest possible emergency supplies, including the sleeping bag and makeshift tent that he'll pitch alone in the wilderness. As well as facing blizzards, moving ice, perilous overflow waters and freezing winds, James will be faced with countless life and death decisions along the way. Recently crowned the fastest ever Briton in a race across the hottest desert, James will now test his body to the opposite extreme as he plans to conquer the Coldest Race On Earth.