The Invisible Library by Genevieve Cogman is an exciting gaslamp fantasy novel that combines elements of steampunk and espionage. The story follows Irene, a librarian who works for the mysterious Invisible Library, which exists outside of time and space. Her mission is to retrieve rare books from different realities, but when she is sent to an alternate Victorian London, she becomes entangled in a dangerous game of wits and magic. With its thrilling plot and unique blend of genres, The Invisible Library is a must-read for fans of gaslamp fantasy.