This is the first part of the trilogy, but I read the second one (Bullet Train) first, and as far as I can judge it doesn't matter. It was fun to discover all the little hints and tips Isaka hides in this story. Also, you actually start liking murderers while reading this. At least I did. How twisted! Of course Isaka manages to do this. It's a bit slower than BT, but this story slowly crept into my heart and I got invested more and more.