Four parallel universes are layered on top of each other. All they have in common is there is a city upon a river called London. Everything else in the world diverged a long time ago when they were separated. Grey London is ours, dull and without magic. Red is resplendent and in balance. White was once all powerful, before Black London fell to the darkest of magics and White was used as a firebreak to stop the spread.

Kell, from Red London, is one of the few remaining magicians capable of traversing worlds. While he transports messages between the rulers of the 3 surviving cities, he also smuggles trinkets for those who would pay a great deal for anything from another world. But when he is tricked into smuggling something far more dangerous than he bargained for he ends up falling in with a thief & aspiring pirate of Grey London, Lila, to put things right.

It’s an interesting world and the stacked nature of the worlds and need for trinkets from each adds a decent limitation to Kell’s powers that everything makes sense and drives the plot forward. Nothing gets too silly when it comes to the uses of magic and the multiverse. I wish we had more of to round out the characters and each version of the city but it’s not significantly lacking given it’s part of a series; it lays a decent foundation there even if it could give more of a hook. I certainly enjoyed Lila.