"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.

In The Son of Neptune, Percy, Hazel, and Frank met in Camp Jupiter, the Roman equivalent of Camp Halfblood, and traveled to the land beyond the gods to complete a dangerous quest. The third book in the Heroes of Olympus series will unite them with Jason, Piper, and Leo. But they number only six--who will complete the Prophecy of Seven? The Greek and Roman demigods will have to cooperate in order to defeat the giants released by the Earth Mother, Gaea....

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.

At the conclusion of The Mark of Athena, Annabeth and Percy tumble into a pit leading straight to the Underworld. The other five demigods have to put aside their grief and follow Percy's instructions to find the mortal side of the Doors of Death. If they 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 both sides and prevent the giants from raising Gaea....

"In response to an awful camp orientation video created by the god Apollo, Percy Jackson and other residents of Camp Half-Blood answer campers' questions such as "What is this place?" and "Do I get to keep the T-shirt?""--

After a summer spent trying to prevent a catastrophic war among the Greek gods, Percy Jackson finds his seventh-grade school year unnervingly quiet. His biggest problem is dealing with his new friend, Tyson-a six-foot-three, mentally challenged homeless kid who follows Percy everywhere, making it hard for Percy to have any "normal" friends. But things don't stay quiet for long. Percy soon discovers there is trouble at Camp Half-Blood: the magical...

A shy twelve-year-old girl must solve a puzzle involving characters from Greek mythology to free herself from a spell which makes her irresistible to boys.

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,...

With help from her new friend Orion, seventeen-year-old Helen Hamilton descends into the Underworld in search of a way to break the Furies' blood curse and prevent the start of another Trojan War.

In this modern retelling of the Persephone myth, Haden Lord, the disgraced prince of the Underrealm, is sent to the mortal world to entice a girl into returning with him to the land of the dead.