Happily married psychotherapist Stella Widstrand, one of three obsessed women portrayed in Swedish author Norebäck's uneven first novel, has mourned the death of her infant daughter for more than 20 years. Isabelle Karlsson, a student at Stockholm's Royal Institute of Technology, feels split between her outward conventional self and her dark inner self. Isabelle's depressed and lonely widowed mother, Kerstin, struggles to hide her caustic resentment from the world. Their lives intersect when Isabelle is referred to Stella for therapy. Stella's belief that Isabelle is her long-lost daughter kindles a protracted psychological pas de trois, and she risks losing her profession, her comfortable home, her caring husband and son, and even her sanity. Short, often jarring glimpses into the feverish minds of each of the three women convey the wavering boundary between mental illness and health. Frequent, often unconvincing plot shifts make it hard for readers to relate to their woes. Hopefully, Norebäck will craft a more persuasive psychological thriller next time. Agent: Lena Stjernström, Grand Agency (Sweden). (Sept.)