Bear Grylls helps Keir Simmons conquer his fears

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Bear Grylls is one of the world’s most recognized faces of survival and adventure, with hit shows such as NBC’s “Running Wild” and several best-selling books. To talk about his latest book, "How To Stay Alive," Grylls took NBC’s Keir Simmons to one of Keir's least favorite places: up high in the air.