It works because Schwab deliberately built her story around two characters who have to live down their own mistakes. And because in the process she built a London (and a London, and a London, and yet another London) that is impossible to look away from. Oh, and also because she put two of the best villains on page into the mix to stir the plot and do their best to cause general havoc and mayhem. All of it adds up to a damn entertaining read.
Kell is a man with a special kind of magic that allows him to travel between the worlds connected by London; one of only two people with the ability. In his normal duties of communicating between the kingdoms he gets bored, and worse, complacent. His habit of smuggling small trinkets between worlds is more for his own giggles than any kind of need. But during a journey into dangerous White London he picks up something is about to cause problems.
Lila is a petty thief that has perhaps gotten more of a reputation than is good for her. When she pretends to help an injured Kell she pockets a certain item that is about to complicate her life. Soon these two are tied together in a desperate bid to right the wrong. Trying to stop them are the evil twins who rule White London, the very confused guards of Kell's own Red London who no longer know what to believe, and the magic of the contraband item itself.
Hang on folks, this will be a ride.
In rapid succession the duo move between the worlds that are better explained within the story than any review can give credit for. They will meet guards with magical weapons, a pissed off magician, and any number of people who no longer are under their own willpower as they are guided into Kell (and Lila's) path. If one is looking for a book that goes places they will not be disappointed here.
And while I started off by calling the two main characters unlikable that doesn't make them uninteresting. Slowly I came around to cheering for them. Lila is a take no shit, barely adult who has made the most of a bad situation by being a fairly bad person herself. She is nothing though if not competent; always underestimated and using that to her own favor. Kell's seeming selfishness also becomes a bit more clear as the story progresses; his life is not all roses as others would assume (and if you have read the book then you know I just made the most subtle pun ever and deserve kudos for sneaking it in).
I liked this book. Sometimes that is enough. A quick look at the synopsis of book two is making me cringe (magical sporting event of some kind, bleh) but as I already have a copy on my shelf I will probably read it anyway. This book was strong enough to warrant another look into the world of multiple London.