As the final battle draws near, Emma finds herself bound under an unbreakable oath. She must seal the bond with Ethon before her transformation, or risk her life and the lives of those she truly loves. Who she wants is no longer an option. Lucian has unleashed troops of evil beasts from the Underworld, making it impossible for Emma to leave the protective barrier of Alaine's home. War is inevitable. The Guardians will need to stay and fight their ground, hoping Lucifer keeps his end of the deal and comes to their aid. In this epic series conclusion, burning questions will be answered, lives will be lost, and sacrifices will be made. But who will survive, and at what cost?