Upon his arrival back in the United States following two decades in the UK, Bill Bryson (Robert Redford) wants to find a way to reconnect with his homeland. Impulsively he decides to hike The Appalachian Trail, 1000 arduous miles stretching from Maine to Georgia. When his old buddy Katz (Nick Nolte), a crude, overweight, recovering alcoholic, calls him out of the blue and offers to accompany him, Bill gets more than he bargained for as they set out on an expedition that men half their age struggle to complete.