Celebrated travel writer Bill Bryson, instead of retiring to enjoy his family, challenges himself to hike the Appalachian Trail --2,190 miles of America's most unspoiled, spectacular, and rugged countryside, much to the chagrin of his wife. The peace and tranquility he hopes to find, though, is anything but, when the only person he can find willing to join him on the trek is his long-lost former friend Katz, a down-on-his-luck serial philanderer.