The Invisible Library [a series by Genevieve Cogman]
I recommend this series to any reader who enjoys escaping into imaginary worlds, and loves reading books about books! Her world building scratched what I will always refer to as my “Harry Potter” itch. An invisible library whose sole purpose is to send their librarian agents out into alternate worlds to capture/claim books for the library? Check! Fae and dragons? Check! Secret agents, a detective who resembles Sherlock Holmes, and an assortment of other possible spies and traitors? Check!

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