The Titan's Curse
Rick Riordan
 Percy Jackson, Annabeth Chase and Thalia Grace, go to Westover Hall in Maine after Grover Underwood discovers two sibling half-bloods named Nico and Bianca di Angelo. They narrowly escape an attack by a manticore named "Dr. Thorn," with some help from Artemis and her hunters, which include Zoë Nightshade. Though they survive the attack, Annabeth is captured by Dr. Thorn. Percy and his friends must look for Artemis before the winter solstice meeting of the Olympian council, when the goddess's influence could change an important vote on the war with the Titans. Percy joins Thalia, Zoe, Bianca di Angelo, and Grover on their dangerous quest. They also are searching for a rare monster that Artemis was trying to hunt down when she went missing; it is so strong that it can obliterate Olympus. Percy is called by a hippocampus to rescue a marine cow-like creature trapped in the Long Island Sound called the Ophiotaurus, whom Percy names Bessie, not knowing it is male. Percy is forced to trail slightly behind the rest of the travelers, catching up with them by flying Blackjack, a pegasus he liberated in The Sea of Monsters to Washington, D.C.. He also spots Dr. Thorn there as well, and follows Dr. Thorn into a private meeting at the National Museum of Natural History, which Percy infiltrates by using Annabeth's invisibility baseball cap. As he watches, Dr. Thorn is severely berated by a man known only as "the General," who uses dinosaur teeth to grow skeleton warriors trained to track down and kill the hunters. Percy races across to the National Air & Space Museum to warn the others, but just as soon as he arrives, the museum is attacked by the Nemean Lion, which they manage to subdue and defeat. When they spot a helicopter following them as they flee, they enter the Washington Metro to throw it off their trail. Apollo finds them at a freight yard and supplies them with a way to Cloudcroft, New Mexico – hopping into cars on an autorack freight train, which delivers them to Cloudcroft the next day. In Cloudcroft, Grover senses the presence of Pan, the Greek god of nature, and a wild gift from him, the giant Erymanthian Boar, comes to carry them further on to Gila Claw, Arizona. It takes them to the junkyard of the gods, and Percy meets Ares and talks to Aphrodite, at which point it is hinted that Annabeth and Percy will most likely have a romantic future. Eventually, the group enters the junkyard, where Bianca tries to steal a statue for her younger brother. She accidentally awakens a prototype of Talos, a giant man of bronze, and dies after being inside the metal giant while it was shocked by telephone poles, but still successfully destroyed it. While being attacked by skeletal warriors at the Hoover Dam, Percy meets Rachel Elizabeth Dare, a girl who can see through the Mist. She saves Percy by confusing the skeletons, allowing Percy and his friends to escape after another ambush by praying to Zeus to animate two angel statues on the terrace, which take them to the Embarcadero in San Francisco. They go to seek the help of Annabeth's father; who, after a brief discussion, lends them his car. They travel to the Garden of Hesperides, where Zoë meets her sisters and is bitten and poisoned by the dragon Ladon while trying to help Percy and Thalia pass. They continue to the Mountain of Despair on Mount Tamalpais up in Marin County, where Mount Othrys, the Titan capital, is now located. From the top of the mountain where Atlas held up the sky, they see Artemis taking on his burden. Annabeth is held captive by Luke, and has been handcuffed and gagged. Realizing that the prophecy made by the Oracle involves him, Percy takes the burden—the Titan's curse—from Artemis. In the ensuing fight, Annabeth's father helps by flying his Sopwith Camel (a biplane) and shooting celestial bronze encased bullets, and Atlas (the General of the Titans) throws his daughter Zoë, slamming her against the rocks. Artemis tricks Atlas into taking his burden from Percy. Zoe dies (because of the poisonous bite from Ladon and the impact of the rocks(caused by her father)) and Artemis turns Zoë into a constellation, in memorial to her. During a battle between Thalia and Luke, Luke falls off a cliff and Percy assumes that Luke is dead. Later, Percy is told by Annabeth, and confirmed by Poseidon, that Luke has survived the fall, and Thalia is asked by Artemis and agrees to join the Hunt to become safer and prevent the prophecy from being fulfilled. They promise each other to hide this fact from everyone else, especially the Titan's army.