It took me a long time to get around to finally picking up this book, but I am so glad that I did. This turned out to be an exciting, interesting and magical fantasy story. Going into this book I knew very little about it. I knew it revolved around different London's and I knew it involved magic. Aside from that I went in pretty open minded.

I really liked the story. I enjoyed learning about the different types of magic: blood magic and elemental magic. The magic in this story was both powerful and interesting, wonderful and terrifying - I loved seeing the numerous ways in which magic was used by the different characters. The plot was action-packed and exciting, culminating in a series of exciting fights, twists and turns. This is an easy read, with a simple writing style and short chapters which suck you in and keep the pages turning.

I really fell in love with the world-building whilst reading this book. The author very cleverly created four separate Londons: Black London, White London, Red London and Grey London. I enjoyed hearing a little about the background of each of these Londons and seeing how different they were from one another. I thought the writing style was beautiful: simplistic yet intricate. I was easily able to visualise these different worlds and I loved how reference was made to points in each London which were solid and kept them intertwined. I would have loved to learn more about Black London and I'm hoping it will come up more in future novels.

The characters were also great! Despite the sheer amount of action preventing the characters from making a huge amount of development, there was more than enough to love or hate about each of them. Kell, our protagonist, is a level-headed, intelligent and complex character. His love for his brother Rhy knows no bounds and he makes some huge sacrifices for him. I also absolutely loved Kell's multiple sided coat, this was such a clever idea by the author. A coat which has many sides and layers in order for Kell to move between the worlds and blend in everywhere. The Dane's terrified me, especially Astrid. The idea of her moving in and out of different people's skins was horrifying and the grin she is described as having is etched on the inside of my brain! Such great villains!

Lila is by far my favourite character from the book. She is strong, independent and sassy. I loved her sarcastic nature and how strong-willed she is. There is definitely something mysterious about her character and her glass eye has sent my mind spinning out theories. I really hope to learn a lot more about her in future books.

Overall, I really, really enjoyed this book. I loved the characters and the multiple Londons. The story ended neatly but I am really interested in learning more about the world, Kell and Lila in the next two instalments. A must read for fantasy fans!