To save the lives of countless people in Captive’s Sound, Nadia has sworn herself to the One Beneath, to black magic. Her plan, and the town’s only hope, is for Nadia to learn enough sorcery to strike back against the forces of darkness. But now that she’s separated from her friends, her family, and her Steadfast, Mateo, Nadia is more vulnerable than ever to darkness. And as the sorceress Elizabeth summons torrential rains and brings the One Beneath closer to the mortal world, Nadia is running out of time to stop her.