Edge of the Unknown with Jimmy Chin

Alex Honnold wants to climb huge walls without a rope.

Skier Angel Collinson falls from a 100-ft mountain.

Gerd Serrasolses reflects on a scary Kayaking mission.

Conrad Anker has a heart attack during a mountain climb.

Travis Rice shares how an avalanche shaped his life.

Climber Will Gadd wants to be the first to ascend the Overhead Hazard route at Helmcken Falls, even if that means risking his life.

Big wave surfer Justine Dupont prepares to ride some of the biggest waves of her life. But to achieve that she has to face down fear and intense risk.

While filming in the mountains of the Grand Tetons, Wyoming, alpinist Jimmy Chin is caught in a colossal avalanche that no one is supposed to survive.

Kayakers Ben Stookesberry and Chris Korbuic went exploring rivers in Central Africa with their mentor, Hendri Coetzee. Hendri never made it back.

Sarah McNair Landry and her brother Eric share their story of kite-skiing the Northwest Passage in winter only to be "hunted" by polar bears.