Published by Hyperion Book CH
ISBN 1423140605 (ISBN13: 9781423140603)

SYNOPSIS:
“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 Death? Much of the prophecy remains a mystery. . . .” 

ABOUT THE AUTHOR:
Rick Riordan is the author of the New York Times #1 bestselling The Lost Hero and The Son of Neptune, the first two books in his Heroes of Olympus series. He also penned the New York Times #1 bestselling Percy Jackson and the Olympians.