Loki the trickster god is free from his chains. He's put together a crew of giants and zombies to sail Naglfar, the Ship of the Dead, in a battle against the Norse gods. If he succeeds, the final battle of Ragnarok will extinguish all the worlds.
With the help from Percy Jackson and my cousin Annabeth, and with friends by my side, I have to sail across the oceans to reach Naglfar before Midsummer's Day. The only problems are the angry sea gods, hostile giants and evil fire-breathing dragons in the way.