In 1808, while Europe burns and the Napoleonic Wars set the world aflame, the HMS Fortitude patrols the sea lanes of the South Pacific, harrying enemies of the British Crown. The Fortitude's captain sets his sights on a Spanish galleon weighted down with a fortune in gold and spices, but Lieutenant Hieronymus Bonaventure thinks the prize not worth the risk. The ship is smashed by storms and driven far into unknown seas, the galleon and her treasure lost in the tempest.

Bonaventure and the rest of the Fortitude's crew find themselves aground on an island in uncharted waters. The island is a place of magic and mystery, promising the crew rest and contentment. But beneath the beauty lurks a darker secret: an ancient evil buried at the living heart of a volcano.