Irene Winters is an agent of the Invisible Library, which has access to a variety of worlds and, consequently, to the rarest books. As a librarian, it is her job to acquire these books. Her latest assignment takes her to a world reminiscent of France during the times of revolution. It’s a dangerous place to steal books, especially when the magical return path to the library is suddenly blocked. What initially seems like a coincidence turns out to be a treacherous attack, one that could destroy the entire library.