If you like one-off stories about unusual people doing unusual things in the mud, here you go. This 220-page tale recounts a trek led by an eccentric Costa Rican with a life-long dream of meeting a remote tribe reputed to live wholly apart from civilization in the pristine mountains of untouched rain forest.

By definition, no one knows what to expect on an expedition; it's therefore easy to screw up on the planning or mis-cast a few of the players. This outing did not go as planned, but served up a heap of glory along with substantial woe. Just think ridiculous uncertainty,...