Nina is supposed to be taking her two children on holiday today with her new boyfriend. But the road away from the isolated winter bleakness of Sandling Island seems to be littered with obstacles, frustrating her plans at every turn. Most pressingly of all, her fifteen-year-old daughter, Charlie, has yet to return from a night out . . . Minute by minute, as Nina's unease builds to worry and then panic, every mother's worst nightmare begins to unravel. Has Charlie run away? Or has something more sinister happened to her? And why will nobody take her disappearance seriously? As day turns to night on the island and a series of half-buried secrets lead Nina Landry from sickening suspicion to deadly certainty, the question becomes less whether she and her daughter will leave the island for Christmas - and more whether they'll ever leave it again.