Will the Greek god Apollo, cast down to Earth in the pathetic mortal form of a teenager named Lester Papadopoulos, finally regain his place on Mount Olympus? Lester's demigod friends at Camp Jupiter just helped him survive attacks from bloodthirsty ghouls, an evil Roman king and his army of the undead, and the lethal emperors Caligula and Commodus. Now the former god and his demigod master Meg must follow a prophecy uncovered by Ella the harpy. Lester's...

Nico, the son of Hades, and his boyfriend Will, the son of Apollo, travel to Tartarus, the deepest, darkest part of the Underworld, as they attempt to rescue an old friend.

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.

Cast down from Olympus and transformed into a human after angering Zeus, a weak and disoriented Apollo arrives in New York City as a regular teen and is forced to survive in the modern world while endeavoring to regain Zeus' favor.

While protecting egotistical transfer student Orion, Artemis makes a mistake that later provides her with the chance that she has both hoped for and dreaded, to prove her courage to herself and others at Mount Olympus Academy.