Each character narrated their own chapters. As to questions 2 and 3, you may be correct. In this novel there is so much deception (outright lying) and dramatic irony it drove me nuts. I can see the movie being either really good or a dud. The theater goers should be actively involved while watching. I'll go see it unless the reviews are just terrible. We'll see. Cheers,
It appears they are going to make a movie based on The Girl on the Train.
The book was read to me on a recent road trip. The book is crazy with an interesting plot and characters- liars, alcoholics, druggies. The movie could be hard to make because the book is mostly narrated.