At the end of the last book in the Waterfire Saga, Astrid left her mermaid friends to confront her ancestor, Orfeo, the evil force behind the rise of the monster Abbadon. Orfeo possesses one of the six talismans that the merls need in order to keep the monster locked up forever. But without the ability to songcast, how will Astrid be able to defeat the most powerful mage in history?<br /><br />Now Serafina and her Black Fins are training goblin troops for battle against her uncle Vallerio's death riders. Will Sera ever see her beloved home and her beloved Mahdi again, or will the Volneros take over the mer realms while Orfeo takes on the gods themselves? Nothing less than the fate of the underwater world is at stake in this breathtaking finale.