A prequel series to his Cirque du Freak books, The Sage of Larten Crepsley follows the life of vampire Larten, who will play such an important part in the later books featuring young Darren. Set three hundred years ago, we meet Larten as a human. We see the world through his eyes, and learn how he has become the person he is.The thing that stands out first is the writing style in Birth of a Killer. It is so different from how Mr Shan has written his Demonata series, which I've read before this one. The language in Birth of a Killer is slightly more formal, richer, more detailed. Especially the more formal part worked really well with the historical feel. It was nice to see that he has such a diversity of writing.Another thing that is remarkable in comparison with his other work is how little action there is in this book. Usually you can count on some kind of big fights at least three times throughout his books, but it felt like Birth of a Killer was way more mellow than his other books. Even though there might not be that much action, this book can still classify as horror. Not because there are demons or vampires in it, but because it describes the horrors of what some human beings can do to each other. You know, the true evil in the world. There was quite some heavy stuff going on in the first part of the book, so I was glad there were also some lighter parts to give some relief. Birth of a Killer is a very quick read, even though it doesn't rely on action to keep it moving. You should see it more like some kind of diary of Larten's childhood and the beginning of his vampire life. Not everything is told; just some key elements that have formed the way he is.For lovers of the Cirque du Freak series, I would definitely recommend Birth of a Killer. Larten is one of the most interesting characters in the series, and he deserves some books of his own. If you haven't read any Darren Shan yet, I wouldn't recommend this book to start with. Especially the mechanics of the vampire society will probably go completely past you if you aren't familiar with the world. Birth of a Killer is different, but not a bad different.