Fever Crumb is the only female Engineer. Dr. Crumb found Fever as an infant and did the only rational thing; take her in and raise her. Fever is now fourteen years old and she has learned to think rational, to think like an Engineer, and Fever helps Dr. Crumb. Fever has never been outside of the head in which all the Engineers live and has never really thought about the world outside of it. Until a man named Kit Solent requests her because he needs the help of an Engineer.After leaving the head Fever's life changes dramatically. She can't understand these thoughts and feelings she's been having. As an Engineer you are taught to have no feelings and only think rationally. But, whatever is happening...She can't control it. While all the changes she is going through, Fever is being chased and meanwhile the whole city is going nuts and preparing for the Movement to come.I won this book from a Goodreads giveaway and when I first signed up for it I didn't realize it was a prequel to the Mortal Engines series, which I haven't read and I think it's great that you can read this without having read the series. The story is set in the future and is really fascinating. The characters are great as well. My two favorite characters have to be Fever and Dr. Crumb. Fever really evolves and goes through many changes throughout the book. Even when she is afraid of what's happening, Fever still tries to be as calm, and rational, as possible. Dr. Crumb I wasn't sure what to think of at first, but later in the book I feel he really becomes a likeable and interesting character.Overall, it was a well-written book with great characters. Now I really want to read the Mortal Engines series.