Large Book

After Annabeth Chase and Percy Jackson fall into Tartarus at the end of The Mark of Athena, the other five demigods of the "Prophecy of Seven" (Frank Zhang, Hazel Levesque, Jason Grace, Leo Valdez and Piper McLean), aided by Nico di Angelo and Coach Hedge, are on their way to Greece to find and close the Doors of Death, so that the monsters of Gaea's army, the primordial goddess of the earth, will not be reborn constantly. In Bologna, the Argo II, the crew's trireme, is raided by the Kerkopes; Leo goes after them to retrieve his stolen Archimedes's sphere, and takes an agricultural book belonging to Triptolemus and an astrolabe made by Odysseus as recompense. He also sends the Kerkopes to harass the Roman army massing at Camp Half-Blood. In Venice, Frank, Hazel and Nico retrieve special barley cakes (designed to protect them from poison in the Necromanteion) from Triptolemus, having done several favors for the god. Frank receives the blessing of Mars for his heroism in Venice, becoming physically stronger and much more confident. During a later encounter with the bandit Sciron and after a meeting with the goddess Hecate, Hazel successfully learns to manipulate the Mist, a power that alters other people's reality layers by deceiving them.