On the eve of their Princeton graduation, two friends are a hairsbreadth from solving the mysteries of the Hypnerotomachia Poliphili, a Renaissance text that has baffled scholars for centuries. Tom Sullivan and Paul Harris uncover a long-lost diary that may prove to be the key to deciphering the text. But when a longtime student of the book is murdered just hours later, a chilling cycle of deaths and revelations begins—one that will force Tom and Paul into a fiery drama, spun from a book whose power is as potent as ever.