The formerly glorious god Apollo, cast down to earth in punishment by Zeus, is now an awkward mortal teenager named Lester Papadopoulos. In order to regain his place on Mount Olympus, Lester must restore five Oracles that have gone dark. But he has to achieve this impossible task without having any godly powers and while being duty-bound to a confounding young daughter of Demeter named Meg. Thanks a lot, Dad.

With the help of some demigod friends, Lester managed to survive his first two trials, one at Camp Half-Blood, and one in Indianapolis, where Meg received the Dark Prophecy. The words she uttered while seated on the Throne of Memory revealed that an evil triumvirate of Roman emperors plans to attack Camp Jupiter.

While Leo flies ahead on Festus to warn the Roman camp, Lester and Meg must go through the Labyrinth to find the third emperor—and an Oracle who speaks in word puzzles—somewhere in the American Southwest. There is one glimmer of hope in the gloom-filled prophecy: The cloven guide alone the way does know. They will have a satyr companion, and Meg knows just who to call upon...

Go west. Capture Apollo before he can find the next oracle.
If you cannot bring him to me alive, kill him.

Those were the orders my old enemy Nero had given to Meg McCaffrey. But why would an ancient Roman emperor zero in on Indianapolis? And now that I have made it here (still in the embarrassing form of Lester Papadopoulos), where is Meg?

Meg, my demigod master, is a cantankerous street urchin. She betrayed me to Nero back at Camp Half-Blood. And while I'm mortal, she can order me to do anything... even kill myself. Despite all this, if I have a chance of prying her away from her villainous stepfather, I have to try.

But I'm new at this heroic-quest business, and my father, Zeus, stripped me of all my godly powers. Oh, the indignities and pain I have already suffered! Untold humiliation, impossible time limits, life-threatening danger... Shouldn't there be a reward at the end of each completed task? Not just more deadly quests?

I vow that if I ever regain my godhood, I will never again send a poor mortal on a quest. Unless it is really important. And unless I am sure the mortal can handle it. And unless I am pressed for time... or I really just don't feel like doing it myself. I will be much kinder and more generous than everyone is being to me—especially that sorceress Calypso. What does Leo see in her, anyway?