The sweeping new historical fantasy novel from Sunday Times bestselling author Katherine Arden.

Anne of Brittany was a child when her land was invaded, her castle besieged, and her royal father driven to his death.

Now Brittany is occupied by her enemies, her treasury empty, and only one thing is lacking to complete her realm's subjugation- she is required, on pain of the sword, to marry the King of France.

But Anne cannot. She has promised her dead father that Brittany would never be conquered.

Defiantly, she betroths herself in secret to France's greatest enemy. But in a world where courts may spy on each other by magic, there is only one way to solemnize this illicit union.

Under the guise of a hunting party, Anne takes her court deep into a deep forest, a strange place dogged with rumours of ancient enchantments; a place where diviners cannot see. She tells the French that she had gone there to hunt unicorns.

It's a ruse, a lie, a feint.

But when, against all expectations, a unicorn does appear and a wounded stranger stumbles from the trees and falls at her feet, Anne is plunged into a world of enchantment where a doomed sovereign might find the power to change the destiny of her nation - or be lost in the mist for ever.