Tess Matheson expects nothing more from her summer job at the boarding school library than to bore herself to death shelving books. But when the insufferable headmaster's son, Eliot Birch, requests a mind-boggling number of occult books, Tess's search for them opens a door to a world of dark magic and forgotten places. She and Eliot find a secret tunnel that leads them to an ancient book. Upon reading it, they discover it's filled with more than words and accidentally release a horrifying devil from his centuries-old prison. The devil will stop at nothing to stay free. He'll manipulate all the ink in the library books to do his bidding, he'll murder in the stacks, and he'll bleed into every inch of Tess's life until his freedom is permanent. Forced to work together, Tess and Eliot have to find a way to re-trap the devil before he kills everyone they know and love, including each other. And compared to what the devil has in store for them, death by boredom suddenly doesn't seem so bad after all.