The book girl on the train is a thriller story which has been very badly written to be very frank.
The main characters of the book are Rachel, Anna, Magan and Scott. So the story revolves around these people only and it has been written in a way that Rachel is trying to tell the story.
So basically the story of the book is that all the characters in the book or depressed in their life unnai constantly think out about all the miseries in their life that they have. Also moving forward we come to know that Rachel travels through a train everyday and while thinking about the miseries that she have in her life she watches a house which he likes very much and she's a couple who are supposed to be living in that house. Without any logic suddenly this constant habit of watching that house while travelling through train becomes an obsession of Rachel and she decides to go to that house. Now at that very point tragedy hits into her life and the story begins to unfold.
Now the reason why I did not like this book are as follows
The book has been written in a very bad manner and I felt that a lot of time the book just gets you bored.
The story telling of the book was very confusing and I felt that a lot of time the author stretched a lot of plots unnecessarily.
One of the major disappointment about reading this book was that at the half stage of this book you kind of very easily realise the thriller part of the story and then the book is just disappointing to read.
So to conclude I don't think you should read this book.