Elizabeth has been married to Michael for ten years, during which she has adjusted to a fairly monotonous routine, including frequent visits to a dank and gloomy house in a Scottish glen that Michael inherited. But then Michael begins to change. It starts when he sees, or thinks he sees, in a painting, the figure of a girl on a landing. But who - or what - is changing Michael? 'Torday carries off a surprising, suspenseful update of Stevenson in the 21st-century Jekyll-and-Hyde thriller.' OBSERVER