In The Son of Neptune, Percy, Hazel, and Frank met in Camp Jupiter, the Roman
equivalent of Camp Halfblood, and traveled to the land beyond the gods to
complete a dangerous quest. The third book in the Heroes of Olympus series will
unite them with Jason, Piper, and Leo. But they number only six--who will
complete the Prophecy of Seven?
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 to find the Doors of Death. What exactly are the Doors of