|Clay Jannon is a young, unemployed graphic designer when he gets a job working the night shift at a strange bookstore. Though it doesn't have many customers, the ones who do visit most faithfully aren't there to buy books but to borrow them. Clay's light-hearted quest to find out what's really going on at Mr. Penumbra's bookstore is a blend of high technology and good ol' fashioned reading and writing. I liked this novel for the most part, although some of the puzzles that were being solved (and the reasons they existed in the first place) didn't make a whole lot of sense if I tried to think about them too much. A quick read with a likable protagonist.