Mac's only friend in the world is a squirrel. Fresh out of the Vietnam war, Mackenzie Peck wants nothing more than to rejoin with his buddies and get back to life as a beer-swilling underachiever. Unfortunately, what he gets is a thankless job at the local Post Office and a string of horribly failed relationships. Now Mackenzie's only hope of finding happiness in his life lies in the furry little paws of wiry, suburban rodent.