In the most harrowing outdoor adventure competition yet, challengers must rely on a combination of endurance racing, survival skills and intuition as they navigate 150 miles of New Zealand's harshest terrain. From the depths of ancient caves to frigid alpine summits, every step and every calorie is hard-earned. However, strength and speed alone won't be enough to win $500,000. Rather, only those with the strongest will to survive can claim this life-changing prize.