Arf

Emma Waterstone is just doing a favor for a friend when she takes over the fortune-telling booth at her local Renaissance festival. She's not expecting to encounter a repellent creature from her nightmares—nor is she expecting Bernard St. Symons, the last of those in charge of battling the things that have crawled out of the Dark Ages.

She'd like to forget that she ever met the Prince of Plagues, but he won't let her. He seems to think she's his ally, and—worse—she's starting to think she might be turning into one.

Along with Bernard and his sidekick, a beagle with special powers, Emma has to figure out how to keep the Prince of Plagues out of the hands of the people who would use him, stop him from convincing her to take advantage of his evil powers herself, and send him back where he belongs.