With irresistible brio and dazzling intelligence, Robin Sloan has crafted a literary adventure story for the 21st century. The Great Recession has shuffled Clay Jannon out of his life as a San Francisco web-design drone, and serendipity, sheer curiosity and the ability to climb a ladder like a monkey have landed him a new gig working the night shift at Mr. Penumbra's 24-Hour Bookstore. But after just a few days on the job, Clay begins to realize that this store is even more curious than the name suggests.