Calphernia Musgrov is a witch, and the last place she wants to be is journeying towards the village of Wallem. Especially with Vesin Eldrade, a ruthless witch-hunter of the Empire.

But times are changing. The Empire's influence is growing, and the old ways are increasingly viewed with suspicion. When a shocking tragedy in Wallem rocks the Five Counties, both women see an opportunity.

For Cal, it's a chance at redemption—to prove her worth in a changing world and overcome the guilt over her partner's death. Vesin, calculating and rigid, is summoned to investigate the disappearances and bring those responsible to justice. Vesin, however, has another motive: to destroy the coven.

Thrown together by fate, Cal and Vesin uncover a much deeper plot, one that threatens not only the Five Counties but the vast Vilnian Empire. Spirits stir; old evils reawaken; and the red star, harbinger of an ancient foe, has reappeared in the night sky. Forced to overcome their prejudices and work together, they must untangle a labyrinth of secrets and confront a rising darkness to save their world.