Every Christmas, Wren is chased through the woods near her isolated village by her family's enemies—the Judges—and there’s nothing that she can do to stop it. Once her people, the Augurs, controlled a powerful magic. But now that power lies with the Judges, who are set on destroying her kind for good.

In a desperate bid to save her family, Wren takes a dangerous undercover assignment—as an intern to an influential Judge named Cassa Harkness. Cassa has spent her life researching a transformative spell, which could bring the war between the factions to its absolute end. Caught in a web of deceit, Wren must decide whether or not to gamble on the spell and seal the Augurs’ fate.