The concept of the book is on par, with the impressive Gone Girl. It turns out the central character who is receiving letters from a girl who went missing 20years ago is actually that girl , but has repressed the torment. Alas not executed as well as Gone Girl. I struggle to see the character as whole because, the book does not fully explain where she thought she had come from? Drug addict that turned into a teacher; how? and what was her childhood before that? Margot as a character was convincing before I knew about Bethany. The book split charters down further into bite size segments, I think the idea was to show her confusion or at least it could have done if executed differently as it was it just felt jerky and found it hard to engage. For example, I also did not feel her getting into relationship with Martin was that plausible .
That been said I did have a gap, between starting Dear Amy and finishing whilst read The Girl with all the gifts for book club so, maybe they contributed to me thinking the book was slightly disjointed. Overall it was a pleasant enough read but disappointed because it had potential to be more powerful and deeper.