Magical in every way. Funny, dark, and radiantly beautiful. So magical and wild that it feels like being swept away by the sea. When Fionn Boyle sets foot on Arranmore Island, the island begins to come alive beneath his feet. Once per generation, the island chooses a new Storm Keeper - someone who wields its power and protects its magic from enemies. The time has finally come for Fionn's grandfather, a mysterious and eccentric old man, to step down. Soon, a new Keeper will be appointed. Fionn's ancestral home has been waiting for him. But deep beneath the earth, someone else has also been waiting. As a battle rages over who will be the next champion of the island, a sinister magic awakens, intent on reigniting an ancient war.