Ruth Hartland is the director of a trauma unit, a psychotherapist with years of experience, wise and respected by her peers. But professional skill is no guard against private grief. The mother of grown twins, she is haunted by the fact that her beautiful, difficult, fragile son Tom, a boy who never 'fit in', disappeared a year and a half earlier. She cannot give up hope of finding him, but feels she is living a kind of half-life, waiting for him to return. Enter a new patient, Dan - unstable and traumatized - who looks exactly like her missing son. She is determined to help him, but soon, her own complicated feelings, about the dissolution of her marriage and her family, about how she has failed her own boy, cloud her professional judgement.