Percy Jackson, who has completed a perilous quest with the young Roman demigods of Camp Jupiter, is about to reunite with Annabeth and the Greek demigods of Camp Half-Blood, and the two groups must cooperate in order to defeat the giants released by the Earth Mother, Gaia. Then, to fulfill the Great Prophecy, seven will have to sail together to the ancient land to find the Doors of Death.

If the five demigods can fight their way through the Gaea's forces, and Percy and Annabeth can survive the House of Hades, then the Seven will be able to seal the Doors of Death and prevent the giants from raising Gaea. But, Leo wonders, if the Doors are sealed, how will Percy and Annabeth be able to escape?

Zeus has punished his son Apollo—god of the sun, music, archery, poetry, and more—by casting him down to earth in the form of a gawky, acne-covered sixteen-year-old mortal named Lester. The only way Apollo can reclaim his rightful place on Mount Olympus is by restoring several Oracles that have gone dark. What is affecting the Oracles, and how can Apollo/Lester do anything about them without his powers? After experiencing a series of dangerous—and...

Four short stories in the form of diary entries, plus interviews, puzzles, and games, reveal new insights into the world of Percy Jackson and the other heroes of Olympus.