When sisters Margaret and Rosie Jaye receive word of their sister Helen's death, they journey to the isolated Blueford Manor. Seemingly cast in an eternal twilight, the estate proves to be full of mysteries: their niece's inexplicable illness, housemaids who never stay longer than a season and a thriving bat colony. As Rosie and Margaret unravel the web of lies surrounding Helen's death, the sisters become entangled in life at Blueford Manor. So much so, that Rosie decides to stay-forever. Unsettled by Rosie's decision, Margaret suspects Helen's widower, the formidable Captain Ford, of influencing her sister. But Margaret's quest for answers is thwarted when Rosie suddenly disappears within the walls of Blueford Manor. As Margaret sets out to unlock the truth, she makes another startling discovery. Adept with a needle and thread, Margaret possesses a dark and unnatural power of her own. Now, Margaret must solve her sister's disappearance and the unanswered questions of Helen's death before Rosie, too, is counted among the dead.