How can a ghost haunt the top floor of a new building? A murder victim's spirit cannot escape the former railway line where he worked and was killed. Other victims of the same incident haunt a young Yorkshire man. A former soldier is researching his father's disappearance when he stumbles across a wartime act of sabotage. A young couple and their son, unaware of the history of the huge stone wall that faces their flat, receive terrifying visitations. But who was the spy, codenamed Sciron, who was responsible for destruction, betrayal and death?