Percy and friends must stop Gaia from sacrificing two demigods in order to awaken and take over the world. Despite surviving their many deadly quests, Percy, Jason, Annabeth and the rest of the crew are no closer to defeating the all-powerful Earth Mother, Gaia. Now her army of giants has risen and they're stronger than ever.
They must be stopped before the Feast of Spes, when Gaia will sacrifice two demigods in Athens. She needs their blood - the blood of Olympus - in order to awaken. But how can a handful of young demigods hope to battle against Gaia's legion of giants?
In spite of the terrible danger that awaits them in Athens, they have no choice. Because, if Gaia wakes, it is game over. For them all.
The fifth book in the bestselling Heroes of Olympus series - set in the high-octane world of Percy Jackson.
NOTE : Contains violence and some kissing.