Magnus Chase, a teenaged einherji (Viking warrior), faces his most dangerous quest yet in this final book of the trilogy. To prevent the Norse god Loki from unleashing Ragnarok—the end of the world—Magnus and his crew of diverse friends must sail the dangerous seas of Jotunheim to reach the Ship of the Dead. Along the way, they must outwit giants, monsters, and Loki himself, using their wits, courage, and teamwork. The adventure tests their bonds and forces Magnus to confront his own fears and what it truly means to be a hero.