The Stranger in the Woods, by Michael Finkel

Subtitled The Extraordinary Story of the Last True Hermit, this nonfiction book introduces us to Chris Knight, a man who spent 27 years living alone in a tent in the Maine woods. Not alone the way Thoreau was at Walden Pond, where he entertained guests and took his laundry home to his mother, but truly alone. In all that time, the only word Knight uttered to another person was a gruff Hi to a hiker he ran into.

Obsessed with avoiding discovery, or even another chance encounter, he never b...