Would you risk your life to save a stranger? A local schoolgirl has been missing for weeks when Margot Lewis, agony aunt of the 'Dear Amy' advice column, receives a letter:''Dear Amy,I've been kidnapped by a strange man.I don't know where I am.Please help me,Bethan Avery.''This must be a hoax. Because Bethan Avery is another young girl, who went missing twenty years ago.As more letters arrive, Margot becomes consumed by finding the sender and - unlike the police - convinced that the girls' disappearances are connected.Solving this puzzle could save someone's life - but could it also cost Margot her own? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .