A thriller in the vein of Gone Girl, but devoid of refinement and complexity of Gone Girl. 
 It is difficult not to draw a comparison between The Girl On The Train and Gone Girl: both feature unreliable narrators, multiple points of view, detestable female characters, a missing wife and a husband whose reactions are questionable. Unfortunately, The Girl On The Train mimics so much about Gone Girl, without adopting the nuance that made the latter so good. This novel is not about moral complexity, nor about the complexity of human relationships. It shifts between narrators, but the voices are characters are utterly indistinguishable from one another. Characters are one-dimensional. The women are all miserable, desperate, boy-crazy messes that are defined by one too obviously dark trait and nothing more (this one is an alcoholic, this one has a baby, this one had a baby but killed it). The characters are pathetic and unlikeable, with no subtlety and no redeeming qualities. The arc of the story is also one-dimensional; it blurs into a repetitive and uninteresting cycle of the pathetic characters repeating their patheticness (oh dear, Rachel is drinking again! And Anna is worried and suspicious! And Megan isn't so sweet after all!). The male characters are so unremarkable and indistinguishable (all of them pleasant on the surface but harboring a vicious streak of violence, rage and promiscuity), that I find it hard to comment on any one of them. 
 Because the characters leave so much to be desired, you find yourself relating to no one, rooting for no one, and hoping, rather, for the plot to keep chugging along and to end cleanly--which it does. So if you're looking for a brainless summer read that, if not for any sort of complexity or humanity, at least has a plot with definite forward motion, it's worth a read. Reader's tip, though: pay no attention to the peppering of train symbols (a pile of clothes by the tracks, rumbling noises, the ominous feeling that trains represent some greater meaning). These add up to nothing.