When Bear Grylls is on set for one of these celebrity duo adventures shows I’m sure he’s used to being the more calm, cool and collected of the two. However, when you invite the world’s best free solo climber, Alex Honnold, you end up taking a backseat in the composure department.  Watch as Alex maintains the heart rate of someone eating a bowl of yogurt while rappeling from a wire bridge over a ravine the Swiss Alps. Dude is comically unflappable:

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