Bear brings along a companion, actor Jake Gyllenhaal, to test how he measures up to unpredictable and unforgiving Mother Nature.

This week Bear braves the remote wilderness of New Zealand's South Island, crossing the country's tallest mountains and attempting to start a fire with wood that is soaking wet.

Bear returns to Iceland to demonstrate the challenge of surviving its many pitfalls. His trek begins on an ice cap covering an active volcano, where food sources are scarce and travels down towards a civilization with swollen rivers between him and safety.

Bear Grylls -- lasso in hand -- crosses a raging river and descends rock pinnacles in Utah.