Lou has always loved Hill House, the derelict manor on the abandoned land near her home. As a child, the tragic history of its owners, the Mandevilles, inspired her dream to become a history teacher. But in her late twenties, working in a shop to pay off student debts, life is passing her by. That changes when a family disaster sends Lou's life into a downward spiral and she seeks comfort in the ruined corridors of Hill House. The house transforms around her and she is transported back to Christmas 1913. Convinced she has been in an accident and is in a coma, Lou immerses herself in her Edwardian dream. With the Mandevilles oblivious to her true identity, she becomes their houseguest and befriends the eldest son, Captain Thomas Mandeville, a man she knows is destined to die in the First World War. Lou feels more at home in the past than the present and when she realises the experience is real she sets out to do everything in her power to save her new friends. She passes between 1913 and 2013, unearthing plots of murder and blackmail, which she must stop no matter the cost. On her quest to save the Mandevilles by saving Thomas, Lou will face the hardest decision of her life. She will learn that love cannot be separated by a century.