The third and final entry into the popular series of Shiloh films, based on the writings of author Phyllis Reynolds Naylor and detailing the captivating journeys of a young boy and his loyal canine companion, find a maturing Marty standing by his troubled neighbor Judd during the drunken townie's most desperate hour. A local man has gone missing, and when authorities find out that he was last seen fighting with Judd, who is already suspected in a series of thefts, they are quick to finger Marty's neighbor as the prime suspect in the unsolved mystery. Though local gossip quickly convicts the weary loner before his case ever even goes to trial, Marty, his father, and his understanding teacher are quick to point out that in the American justice system people are to be presumed innocent until proven guilty.