DO YOU PROMISE NOT TO TELL?A DAUGHTER:Beth has always known there was something strange about her daughter, Hannah. The lack of emotion, the disturbing behaviour, the apparent delight in hurting others… sometimes Beth is scared of her, and what she could be capable of.A SON:Luke comes from the perfect family, with the perfect parents. But one day, he disappears without trace, and his girlfriend Clara is left desperate to discover what has happened to him.A LIFE BUILT ON LIES:As Clara digs into the past, she realizes that no family is truly perfect, and uncovers a link between Luke’s long-lost sister and a strange girl named Hannah. Now Luke’s life is in danger because of the lies once told and the secrets once kept. Can she find him before it’s too late? .