A cleverly plotted, realistically frightening, addictive story with some intriguing and darkly fascinating twists and turns that kept me reading into the early hours of the morning. At the end of The Night Sister, I was left seriously considering the terrifying way the story unfolds: two sisters, Rose and Sylvia Slater are left largely to their own devices while growing up in the small town of London, Vermont. Strafing three time periods, the novel begins as Piper arrives in London from Los Angeles, ostensibly to look after her pregnant sister, Margot. But she’s hardly settled back into her home before Jason, Margot’s policeman husband, tells her the terrible news about Amy, her best childhood friend.

Both sisters feel a gut punch of loss and struggle to recover from the shock, but another feeling of fear worms its way to the surface: the gunshots and screams that came from the old Tower Motel where Amy and her family still lived; and the worrying movements of Jason, who visited Amy a week before to check to see if she was alright. Amy had called Jason out of the blue, telling him there was something crazy that her mother, Rose, said, something that he hadn’t been able to stop thinking about.

As Jason’s headlights illuminate the faded and rotting old sign--“Tower Motel, with its 28 Rooms”--and the house itself, musty and vaguely ruined, the narrative switches to Piper and her recollections of her friendship with Amy, who made it clear that she didn’t want to remain friends even though Amy used to make Piper feel invincible. The tragedy forces Piper to remember Amy’s mother and her Aunt Sylvia and the tale of how Sylvia disappeared decades ago. She also recalls Jason, who followed her and Amy around that long-ago summer back in 1989, this sensitive, diffident boy who once wrote Amy love poems in secret code and watched both Piper, Amy, and ten-year-old Margot from the shadows of the Tower Motel. Jason was always spying and always trying to catch Amy’s eye.

A hint of torture is always near, most symbolized by the formidable Tower itself, built by Rose and Sylvia’s father back in the 1950s. The Tower is a haunted and precarious space that hints at the goings-on in the human psyche. From the pain of Sylvie’s letters to Alfred Hitchcock, telling him that she is going to Hollywood to make movies, to her fraught relationship with Rose, to the joy they both have of hypnotizing chickens, to handsome Uncle Fenton, the fix-it man at the hotel who lives in the a trailer behind the house, these early sections of the novel focus on impressionable Rose and her dreams in which a dark formless beast overtakes her, pinning her down; and of Sylvia, always distorted, for once not the beautiful one but something strange and hideous: “an orange faced monster.”

This ambiguous reality of the novel reaches not only into Rose’s perception of Sylvia but also into the actions and motivations of Amy and Piper and Jason. What is real here? And whose innocence is being corrupted? Dark-featured Rose has a curious nature and a maturity combined with a childishness, but she seems to be suffocating under the weight of so many secrets. Both Piper and Jason visit Rose, now suffering from dementia and placed in a nursing home by an increasingly paranoid and frightened Amy, in an attempt to get some answers. Amy is certain that her mother was somehow linked to the strange goings on at the Tower Motel, still haunted by strange and terrible creatures with wings, hideously sharp claws, and mandibles for a mouth.

Clearly there is evil here, but its emanation is ambiguous and amorphous. For Rose, it forms a presence that seems unholy, most manifested in her dreams of claws and fangs and blood, as though something is sleeping beside her each night and moving deep inside her. Effortlessly moving from 1955 to 1989, and to 2013, McMahon’s novel echoes with the rhyme of death. There always seems to be a rank, malevolent odor, something moldering. Even Piper remembers Amy’s Grandma Charlotte reciting that same little rhyme to both her and Amy so many years ago.

The suspense is ethereal and nothing is sure in this painstakingly constructed mystery wrapped around sibling tensions, both in the past and in the present. Beautiful and creepy, the novel is an unusual blend of poetic language, dark family secrets, and things that have been left unsaid. Although McMahon sells herself out with the supernatural elements (a cheap plot device in order to wrap things up?), she surprised me again and again by turning the typical thriller on its head, equipping her characters with just enough power, force of will, and strength that we rarely get to see in such dark and twisted fairy stories.

• Burn Town
• The One I Left Behind
• Don't Breathe a Word
• Dismantled