My memories of Grace never added up to how she really was. She was always impossible to pin down, dancing just out of my reach, exactly as she did when she was alive. Nora was a girl of twelve when the war broke out and she was forced to join the train-loads of evacuees leaving London's East End for rural Kent. Her surrogate family, the Rivers, are unlike anyone she has met before and she soon comes to love her new life with them, and in particular with twelve-year-old Grace. Over the next few years, as the dogfights rage ever more fiercely over head and it becomes clear that the Rivers marriage contains deep and irreparable cracks, Nora and Grace grow as close as sisters - though, to Nora's confusion, even this is not quite as close as she would like ...What happened next is a secret that will gnaw away at Nora for the rest of her life - a secret that she can only begin to tell when she is certain that she is approaching the end.