5 of 5 stars
Rear Window meets Gone Girl in The Girl on the Train, the debut novel of former journalist Paula Hawkins. Rachel Watkins is the eponymous girl, in actuality a 30-something divorcee still reeling from the breakup of her marriage, for which she takes the blame, all of it. Her ex, Tom, remarried instantly and now resides where he and Rachel lived with his new wife, Anna, and year old daughter. Rachel can’t stop herself from hounding them with tearful, demanding phone calls, most placed in the middle of the night. The novel’s plot revolves around what Rachel sees everyday on the train to London, which passes by the back gardens of her former house and neighborhood. A strong first clue to Rachel’s state of mind lies in the fantasy she spins out daily about a couple she observes having coffee each morning from the deck of one of the other houses. Another comes when it becomes apparent how much wine and gin she’s habitually drinking. Finally, we learn that Rachel is taking the train each day to preserve the illusion that she still has the job that she lost because of her drinking problem. One morning she sees the woman, Megan, kissing a man not her husband, and a few days later, Rachel’s shocked to learn that Megan has, as they say in the UK, gone missing. She offers information about that stolen kiss to the police, who consider her an unreliable witness, so she chooses to tell Megan’s husband, Scott.
Rachel is the protagonist in the story, as unreliable a narrator as ever conjured up in the pages of a book. As she becomes immersed in the mystery, she grows more and more unstable, and begins having vivid flashbacks to traumatic experiences that she doesn’t remember. Her point of view, mainly stream of consciousness, alternates with those of Megan and Anna, who are as grounded in denial as Rachel is. All three characters are profoundly disturbed, though at first it appears that Anna and Megan are more functional than Rachel. Tom and Scott, while having no narrator duties, show themselves to be abusive and manipulative. What makes The Girl on the Train so compelling is the remarkable way in which Paula Hawkins presents the interplay among the characters and the manner in which they tailor their perceptions and behaviors to suit their personal needs and self images. Sometimes we all delude ourselves, of course, but these characters have lost their own integrity and connection to reality. We never can tell quite what is lurking right under their facades. As their narratives come together during the latter chapters, the suspense becomes intense, more so because there hasn’t been a lot of warning (few telling slip ups here) and we aren’t quite sure how any of these people will react. Despite the dark, depressive atmosphere, which never really eases, there are glimmers of hope at the end, but this is no easy beach read.
You're History! 
I really like this one, as well.