Rowan's supernatural powers become a terrifying burden. In New Orleans, teenage Deidre wants to break free.
Rowan suffers from grief over Ellie's death, loses control of herself and becomes unable to perform surgical operations. In New Orleans, Deidre and her mysterious companion Lasher join forces to bring Rowan home.
In the wake of Deidre's horrific death, Rowan seeks protection in a strange city, and Ciprien offers her a safe place while he looks into Deidre's murder. Lasher reaches out to Rowan, but in unexpected way.
During Deidre's funeral, Rowan digs into the secrets of the Mayfair family. Uncle Cortland and Aunt Carlotta argue over Lasher, while Rowan must choose a side and face the consequences, and Ciprien discovers the identity of Deidre's killer.
After finding themselves trapped in the First Street House, Rowan and Ciprien are forced to confront mysterious puzzles to find a way out, while Rowan wrestles with an unimaginable offer, and Ciprien's sister, Odette, discovers something terrifying.
Eager to get rid of Lasher, Rowan seeks help from her extended Mayfair family. She must have faith in their unusual process, a sacred ritual, and Ciprien's search for answers leads him back to the Talamasca.
Tessa is kidnapped by witch hunters and they try to burn her alive, but Rowan saves her. A tragic event leads Rowan to become closer to the Mayfair family and Lasher, and Ciprien is trapped in another illusion created by Lasher.
Rowan accidentally finds out her part in a prophecy that has baffled the Mayfair family for generations, as Ciprien's investigation comes to an end, revealing secrets that could destroy both Rowan's family and his part in the Talamasca.