The book was very interesting. It is very similar to the movie. I enjoyed the book because, while I was reading it, I felt captivated. However, there were some details that were better described on the movie than on the book, but definitely the book had some more information than the movie. The actors pretty much based their speeches and dialogs on the book. That's what made the movie more pleasant.
I would certainly recommend it to my friends who like to read thriller books.