Kell is one of the last of the Antari, or Travelers, blood magicians able to move between alternate universes. His world is the world of Red London, where magic is common, and supports a healthy, thriving society. Kell serves the King and Queen, and has been raised as a brother to the Crown Prince, Rhy. He feels like a brother to Rhy, but to the king and queen, although they are kind, and warm, and generous, he feels more like a valued possession.
One of his duties as the Crown's Antari is conveying messages to and from the other Londons--or rather, to and from White London and Grey London. Black London is dead, completely closed off, and a rebuke and warning to the other Londons. White London is closest to Black London, and cold, drained of color, and ruled by a murderous pair of twins, Astrid and Athos Dane. Grey London is our London, and gives us the time setting: It's Regency London, with George III floating in and out of rationality and coherence.
As Kell carries his official messages between the monarchs, he also indulges a dangerous hobby: smuggling small artifacts among the worlds, trading them with collectors eager for even a small piece of a world they'll never see. And one day, he accepts the wrong artifact, something that once unwrapped proves to be a relic of Black London.
Even having it is treason, but worse than that, it threatens to bring to Red London the same disaster of out-of-control magic that destroyed Black London.
Fleeing back to Grey London to work out a way to get the dangerous thing back to Black London, Kell runs afoul of cutpurse Lila Bard--and then he rescues her, and she rescues him, and soon they are so entangled with each other that his mission has become their mission.
And Kell's troubles haven't even begun to get complicated.
There's a lot going on here, in the world building, the magic system, and the character development. Kell and Lila are both worth the time spent with them. The world seems claustrophobic at first, but as the story progresses, we get a sense of a full, complete world beyond the Londons. This is the first of a series, and while there is a satisfyingly complete story within this book, there are also clear hints that both Kell and Lila have secrets in their past that they don't know about, and that are going to matter in future volumes.
All in all, I found this engrossing and enjoyable. Recommended.
I received a free copy of this audiobook from the Ford Audiobook Club.