I couldn't put this book down, it kept me reading until very late at night. It is a great thriller, has a really good build up of tension. It kept me on the edge of my seat the whole time. The only thing that I think it missed is some big plot twist. Even though it kept me guessing and doubting the main character, I think it still needed some twist. But it did make me get out of my bed and check if I locked the door. :)