The triumphant conclusion to New York Times bestselling author Claudia Gray's dazzling Spellcaster series. To save the lives of countless people in Captive's Sound, Nadia swore 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 evil. But now that she's separated from her friends, her family, and her Steadfast, Mateo, Nadia is more vulnerable than ever to the growing darkness. The final battle lines are drawn, surprising alliances are made, and true love is tested in the action-packed conclusion to the breathtaking Spellcaster series.