"The Greek and Roman demigods will have to cooperate in order to defeat the giants released by the Earth Mother, Gaea. Then they will have to sail together to the ancient land--Greece itself--to find the Doors of Death"--Provided by publisher.

Based on the publishing phenomenon, Percy Jackson and other young demigods continue to fight, but this time in the sea, to fulfill their destinies. To save their world, Percy and his friends must find the fabled and magical Golden Fleece. Embarking on a treacherous odyssey into the uncharted waters of the Sea of Monsters (known to humans as the Bermuda Triangle), they battle terrifying creatures, an army of zombies, and the ultimate Evil.

Demigod Percy Jackson, still with no memory, and his new friends from Camp Jupiter, Hazel and Frank, go on a quest to free Death, but their bigger task is to unite the Greek and Roman camps so that the Prophecy of Seven can be fulfilled.