The story follows the Greek god Apollo, who has been turned into a human teenager named Lester Papadopoulos, in his quest to free five oracles of Ancient Greece from Triumvirate Holdings, a group of three evil Roman Emperors, in order to regain his immortality.

Apollo, in the body of the 16-year-old Lester Papadopoulos, ventures through the Labyrinth with 12-year-old Meg McCaffrey and the satyr, Grover Underwood in a bid to find the third emperor of the Triumvirate Holdings.

As the trio face a continuous attack of Strix, Grover unleashes the cry of Pan, the lost god of the wild, and brings them to Aeithales, which is later revealed to be Meg's former home, in Palm Springs, California.

Apollo and Meg pick up Piper, who is moving away to Tahlequah, Oklahoma, and Jason, who is at school and occasionally has fights with monsters disguised as teachers.

Jason secretly tells Apollo that he had met with Herophile, the sibyl inside the Labyrinth, who told him that when the next time the duo comes, one of them will die.

They escape with the help of Crest, a young Pandai, and Apollo finds the shoes, but then they are captured by Incitatus the right-hand horse of Caligula.

Facing certain death, Apollo decides to find the cause of the flames that have been engulfing the southern lands for a long time and discovers the faded but still burning body of Helios, the former titan of the sun being used by Medea in order to make Caligula the new sun god, and Apollo promises to exact revenge for Helios.

Jason's body is given to Apollo for burial at Camp Jupiter, and Leo takes Hedge, Mellie, and Piper to Oklahoma.

1 on Amazon's Teen & Young Adult Greek & Roman Myths & Legends bestseller list[8] and the Kindle ebook at No.

[13] In the United Kingdom and other Commonwealth nations, English-language editions in hardcover were also released May 1 by Puffin Books with cover art by Ben Hughes.

[3] Additionally, Barnes & Noble released a special edition exclusive to its customers, which also included a removable puzzle collection.