Not all books should be opened.

'A book of magic about books of magic . . . a bold, new novel from an extraordinary new voice.' Marlon James, Sunday Times bestselling author of Black Leopard, Red Wolf

Joanna Kalotay lives alone in the woods of Vermont, the sole protector of a collection of rare books; books that will allow someone to walk through walls or turn water into wine. Books of magic.

Her estranged older sister Esther moves between countries and jobs, constantly changing, never staying anywhere longer than a year, desperate to avoid the deadly magic that killed her mother. Currently working on a research base in Antarctica, she has found love and perhaps a sort of happiness.

But when she finds spots of blood on the mirrors in the research base, she knows someone is coming for her, and that Joanna and her collection are in danger.

If they are to survive, she and Joanna must unravel the secrets their parents kept hidden from them - secrets that span centuries and continents, and could cost them their lives ...