[1][2] English teacher Doug Albin, his wife Tritia and their son Billy live in the small town of Willis, Arizona, and are shocked to learn of the suicide of their friendly, beloved, and seemingly content long-term mail carrier.
A replacement arrives by the name of John Smith, an evasive and vaguely threatening man with pale skin and flame-red hair.
In this way he exposes the weak veneer of civilization, being able to make savages of ordinary people just by the letters that appear in their mailbox, purporting to be from friends and family members, destroying their faith in the outside world.
For instance, he makes one believe that his younger brother, who died in the Vietnam War, sent him letters revealing himself to be a jaded psychopath who raped and murdered native girls.
The exact nature of the mailman and his motivations are never fully explained, though he is clearly a sadistic demonic entity that finds expression through the US Postal Service.