Adam works night shifts at a motorway service station, living a small and lonely life with little human contact or connection. Upon hearing that his estranged father has died, Adam finds himself piecing together a complicated image of a man that he never really knew and uncovers details of his life that he struggles to comprehend. Learning that his father believed he was not human, Adam initially dismisses the notion outright. However, unable to shake the thought, he begins to wonder: if this were true, what would that make him?