I want to start of this review by saying that this book was an amazing fantasy novel! This novel was extremely unique from the other novels that I've been reading and that was really refreshing. 
 The first thing that made this novel so amazing was the plot. Kell and Lila meet each other in a series of unfortunate circumstances and then must work together to return a dangerous object to it's home before they get killed. The plot liked I mentioned before was really unique and fresh. It was fast paced and kept me on my toes (and always wanting more :) ). 
 The next thing I really loved about this book was the setting (or settings rather). There are four Londons in this novel, Red, Gray, White, and Black, with varying levels of magic. I absolutely loved the way Schwab described each one of these Londons because I actually felt like I was apart of each one. 
 Finally, I loved the characters in this novel. We have two main characters, Kell and Lila. Kell is an Antari, last of his kind, and has the ability to travel between the parallel Londons. I really liked Kell's character because he's a little of both good and bad. His bad side can be seen as he smuggles goods between the two Londons. But in other parts of the book you can see his good sides. Even though Kell isn't a normal human, Schwab creates his character in a way that one can still relate to it. Our other main character is Lila. Lila is feisty, smart and badass thief from Grey London where almost no magic exists. Lila pretends she has no heart and doesn't care for anyone but in some parts of the book (no spoilers :) ) one can see that she really does care :) The other somewhat main character in the novel was Kell's "brother", Rhy. Ray is the prince of Red London. Rhy is pretty understanding but is a strict follower of rules. He wasn't tat prominent in this book but I have a feeling he will show up a lot more in the next installment of this series. Finally, I absolutely loved the friendship that started to build between Lila and Kell. In the beginning they barely trust each other but when they are forced to come together to survive they start to really build a relationship. I can't wait to see what they're friendship (romantic? ;) ) will be like in the next book. 
 Overall, I think that the plot, setting, and characters make this a worthwhile fantasy read for everyone :)