Joanna lives alone in the Vermont woods, the sole protector of a collection of rare, magical books. Her older sister Esther moves a lot, desperate to avoid the deadly magic that killed their mother. But when Esther is working on a research base in Antarctica and she finds spots of blood on her mirrors, she knows that Joanna and the collection are in danger. For the sisters to survive, they must unravel the secrets their parents kept hidden ... Perfect for fans of Deborah Harkness.