I don't usually rave about a book but that's what is going to happen, I know it. This book is an amazing conclusion to a marvelous trilogy that just kept getting better as it went along. The pace is relentless, the action is non-stop and there's hardly a moment between one interesting scene and the next. Besides all the steampunk goodies we also get to meet Nikola Tesla and Pancho Villa. Both are portrayed very convincingly. Scott Westerfeld really wrote this series well. It's not overly melodramatic, the dialogue is neither windy or sparse, and there are oodles of creativity in the settings and the characters. The very ending I knew was going to happen but it didn't detract from me enjoying the book at all. In a way I don't want this series to end because it was so damn good but I think the right decision was made to limit it to three books. What's that you say? You're not into steampunk? Read this series anyway, you'll be glad you did.