Leaving the safety of the demigod training ground, a disgraced Apollo embarks on a quest across North America to find a dangerous ancient-world Oracle while navigating the challenges of the evil Triumvirate.

"The Greek and Roman demigods must simultaneously prevent the earth mother, Gaea, from waking and stop war from breaking out at Camp Half-Blood"-- Provided by publisher.

"A deadly plague has struck Olympus and is slowly aging and killing the Olympians. Emily can only stand by and watch as those she loves fade and die. But in one last desperate attempt to save those she loves, she journeys back to Earth to face the CRU, then back in time to confront Cronus, leader of the Titans and father of the gods"-- Provided by publisher.

"Pegasus and Emily investigate a series of incidents back on Earth, and discover that the CRU has been cloning Olympians"-- Provided by publisher.

Caught in the middle of an ancient power struggle, Emily and Pegasus must venture to Diamond Head volcano in Hawaii to track down the one thing that can save Olympus--before the Titans get there first.

The Greek god Apollo, cast down to earth as the ungifted human teenager Lester Papadopoulos, and his demigod friends must go through the Labyrinth to find the third emperor--and an Oracle who speaks in word puzzles--somewhere in the American Southwest. The Greek god Apollo is still in the persona of ungifted human teenager Lester Papadopoulos. Now Lester and his demigod friends must go through the Labyrinth to find the third emperor-- and an Oracle...

After learning that he is the son of a mortal woman and Poseidon, god of the sea, twelve-year-old Percy is sent to a summer camp for demigods like himself, and joins his new friends on a quest to prevent a war between the gods.