Review Detail

What works: The City of Spies is a six-book middle-grade series about young adults who are spies for opportunities when adults would stick out like a sore thumb. They remind me a lot of the Spy Kids movies I grew up watching and give you the same thrilling connection of having a family and doing whatever it takes to get the job done while leaning on the support of your family. I also love how we have the original team members but now have the addition of Annie and Cario, the mother’s actual children, who now have a whole group of siblings with whom they can connect. Many questions are wrapped up in this book from the previous books in the series, and it almost feels like the author is going in a new direction with the story, which would make for a refreshing change of pace after six books. I also love how middle-grade readers can explore places like Istanbul, Scotland, Paris, Rome, and London through the thrilling lens of a spy adventure. 
Final Verdict: The spy aspect of this book is more of a hunt, this time, with clues to follow (before it unfolds into more later on), so mystery fans will appreciate that end. While this involves spies, the technology and abilities don't stretch the imagination too far, and the characters expand their capabilities and trust in themselves, which adds a nice touch. The family aspect is inspiring and makes this group golden, as they are a bit of a hodge-podge mix but still hold together wonderfully.

London Calling is a nice addition to the series. It keeps everything exciting and tension-packed while still leaving an option for another thrilling adventure in book seven.