Rick Riordan

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.

"The Greek and Roman demigods will have to cooperate in order to defeat the giants released by the Earth Mother, Gaea. Then they will have to sail together to the ancient land--Greece itself--to find the Doors of Death"--

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.

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...

"In his penultimate adventure, a devastated but determined Apollo travels to Camp Jupiter, where he must learn what it is to be a hero, or die trying"-- Provided by publisher.

Percy Jackson's hope for a normal senior year is shattered as the gods present him with three quests, beginning with the retrieval of Zeus's goblet, in order to get the necessary three letters of recommendation for college.

Magnus and his friends set sail for the farthest borders of Jotunheim and Niflheim in pursuit of Asgard's greatest threat, Loki's demonic ship full of zombies.

Fourteen-year-old Amy Cahill and her younger brother Dan thought they could return to their regular lives when they found the 39 clues. But the Vespers, powerful enemies, will stop at nothing to get the clues. And with the Vespers rising, the world is in jeopardy.