A year ago Adrian and Magnus walked out of the dungeons of their king, Gabriel, but his renewed favor is tenuous. Now they have an opportunity to make amends for good: to steal a book Gabriel desires from Lorenzo de' Medici, the most powerful man in Florence, on the condition that they do so without being detected. To secure their prize, they decide to talk their way into Lorenzo's home-save that Adrian and Magnus are not men, but what later centuries will call vampires. Unable to walk in sunlight without burning, fearing discovery by the Florentines, they find themselves relying on an unlikely intercessor: a young monk named Girolamo Savonarola, already famous for his visions. Soon, however, Adrian and Magnus realize that nothing about their task is what they expected, and their success could have catastrophic repercussions. To survive Gabriel's dark agenda, they will have to confront their shared past-or risk sacrificing their future.