Ingrid Torfudottir moved to the North Shore of Lake Superior intending to live with her grandmother while pursuing a career as a book illustrator. Instead, she discovered her true calling as a volva—a Viking witch—serving a village founded in the Viking age by Norse settlers escaping some terrible enemy whose identity was lost to time.

Now she lives in the hidden town of Villmark full-time. Her boyfriend Thorbjorn and her best friend Loke remain in the wilds far to the north of Villmark, their fates a mystery to those they left behind. Like Ingrid.

And like Esja, Loke's sister. Ingrid awaits the next evolution of Esja's destiny, so intertwined with her own. What happens next will test them both.

But then the unexpected occurs. Something preys on the women of Villmark, killing them in the very streets of the town. And Ingrid and Esja both swear to catch this predator before it strikes again.