Following the death of her estranged father, Jessica Lace travels to his remote Scottish home. She soon discovers that, in his final years, her father became increasingly concerned about the possibility that he was being haunted.As she explores the house, Jessica begins to wonder why her father had the place divided up into three separate apartments. He was never able to rent out the empty spaces, instead leaving them to sit untouched while he lived in just one small part of the house. Meanwhile, local people continued to whisper to one another that the ghost of a long-dead woman - the mysterious Ethel Hogsflesh - could sometimes be seen at the house's windows.Jessica soon decides to knock down the walls that her father put up. As she does so, however, she begins to understand why he had those walls installed in the first place. Was the house really haunted by Ethel's ghost? If so, did her father discover a way to ward her off? And is Jessica in danger of undoing all his work and unleashing a horrific force of evil?By the time she realizes that the truth is so much worse, Jessica might have made a mistake she can never take back.