Randolph Tiefenthaler insists he had a normal childhood, though he grew up with a father who kept thirty loaded guns in the house. A modestly successful architect with a wonderful family and a beautiful home, he soon finds his life compromised when his father, a man Randolph loves yet has always feared, is imprisoned for murder.

Fear is the story of the twisted events leading up to his father’s incarceration. It begins when Randolph and his family move into a new building and meet their neighbor, Dieter Tiberius, the peculiar yet seemingly friendly man living in the basement apartment. As the Tiefenthalers settle into their home, they becoming increasingly disturbed as Dieter’s strange behavior turns malevolent. Randolph unravels the tale of Dieter’s harassment—the erotic letters he sends to Randolph's wife Rebecca, his spying, his accusations of child abuse, the police reports he filed against them. Finally, Randolph admits his of own feelings of desperation and helplessness, which ultimately led to his father’s intervention.

As Randolph plumbs the depths of his own uncertainty surrounding the murder—pondering fundamental questions about masculinity, violence, and the rule of law—his reliability is slowly but irrevocably called into doubt. The result is an unsettling meditation on middle-class privilege and "civilized life" that builds to a shocking conclusion.