The synopsis for the series reads: “Nathan tries to do the right thing but he lacks direction and is carrying a long-buried secret that he is desperate to keep hidden.
“Having started a new life as a devoted married man, Nathan’s world is turned upside down when a ghost from his past, Bob (Bertie Carvel, Doctor Foster), turns up on his doorstep.
“Bob reveals some shocking news which has disastrous consequences and leads to a journey of psychological suspense, love and potential redemption.”
Creator Neil Cross spoke exclusively to Express.co.uk and other press about whether The Sister was based on any real events, to which he gave a haunting response.
The series is not based on a true story but instead, on a terrifying dream he had.