I got suckered into reading this by the other reviews and its featured status on this website. This is not a good book. There are no plot twists or interesting turns at all. This takes place in a world where you can immediately assess someone's guilt by how they look. Thus when you meet a character who looks shady and untrustworthy, sure enough it turns out to be a brass thief. A waste of time.
Disclaimer: I am a grown-up. But I don't think kids would like it either. In fact, I read the first chapter to my 9 year old son (before I knew it was bad) and he didn't want to hear the rest. I should have listened to him. I was waiting for the plot twist that never happened.