Four explorers are lost in the Peruvian jungle.
Scientists are on a dangerous expedition into the heart of an active volcano.
An extreme marathon runner, cut off by sandstorms, is stranded in the Sahara.
Four American climbers scale Kyrgyzstan's granite walls. Now, they're hostages in a terrorist battle.
In the Himalayas, four kayakers try to conquer the world's most dangerous river.
Follow a team of mountain climbers as they attempt a challenging ascent up the treacherous slopes of Mt. Hood.