In the faerie world of Gryphendale, a new generation reaches adulthood and strikes out on their own adventures...

An unusual brownie adventurer named Arthur, and the twin princes, Timothy and Nathaniel, join forces to travel to the underside of their coin-shaped world to break the curse that has turned Nathaniel's fiancée into stone.

Arthur must face his traumatic past as he leads Nathaniel and Timothy on the same journey that killed his friends more than forty years before, getting them all stuck far from home with only one impossible way home.

Things continue to go wrong when they learn that this curse is just the beginning of more significant problems threatening to destroy the Guardian of the Ocean.

Struggling through a debilitating injury, Nathaniel must risk everything to save the ones he loves. Timothy must let go of his dark magic past to use his fire magic against the alliance that threatens to destroy the world with water.