Gone Girl the book adds much more dimension to the characters, especially Nick, than the movie. The inclusion of the diary entries between Nick's POV added an interesting element by making you feel like you’re reading not a mystery but just a book about a lady which, if you’re in for that is great, but if you're expecting a book like Sharp Objects you'll be disappointed. The focus of the book is on the unlikable characters and exploring their motivations and how being morally grey (even that may be an understatement) is what makes the characters interesting. Their lack of growth is fascinating to well adjusted people.