'Gone Girl': Two Books in One

I believe that the best review of Gillian Flynn’s Gone Girl must include a discussion of the mystery’s revelations, not just its set up. The first part of this review assumes that you have not read the novel and don’t want to know what happens (and, in my humble opinion, serves as a perfectly fine assessment of the novel on its own). The second part of this review assumes that you have read the novel or don’t care if you know what happens.