Percy, Annabeth, and Thalia fly by pegasus to Olympus, where Percy feels uneasy about facing all twelve Olympians at once. Inside the throne room, they see Zoë’s new constellation overhead, Grover with Bessie in a floating sphere of water, and the assembled gods preparing to judge the quest’s results.

Artemis reports that Olympus now understands the danger: Mount Othrys is rising, Atlas tried to escape, and Kronos’s armies are gathering. The gods vote to respond by hunting powerful monsters, checking the Titans’ prisons, and allowing Poseidon to attack the Princess Andromeda. Artemis argues that Percy, Annabeth, Thalia, and Grover deserve rewards, but Ares and Athena warn that Percy and Thalia are dangerous because the Great Prophecy concerns children of the eldest gods.

The council also considers killing Bessie, the Ophiotaurus, because sacrificing the creature could give a child of the eldest gods power to destroy Olympus. Percy argues that Bessie is innocent and that killing him out of fear would make the gods like Kronos. Before the issue is resolved, Artemis announces that she needs a new lieutenant and asks Thalia to join the Hunt.

Thalia accepts Artemis’s offer, pledging herself to the Hunt and avoiding her sixteenth birthday, which means the Great Prophecy will no longer be hers. Thalia says she has finally found a home and tells Percy that he will be the one in the prophecy. Poseidon then vouches for Percy and Bessie, agreeing to help build a protected aquarium for the Ophiotaurus on Olympus; a majority of the gods vote to spare them and celebrate the heroes instead.

During the Olympian party, Percy receives congratulations but remains aware of the risks Poseidon has taken for him. Poseidon privately warns Percy that Luke is alive, sailing from San Francisco with Kronos’s strengthening golden coffin, and that older ocean spirits may protect Luke from Poseidon’s storms. Poseidon also explains that Atlas cannot easily force the sky onto anyone except another Titan, unless a true hero chooses the burden freely.

Athena then confronts Percy and explains why she considers him dangerous: his fatal flaw is personal loyalty, which Kronos has repeatedly used by threatening Percy’s loved ones. Athena also says she disapproves of Percy’s friendship with Annabeth. Shaken, Percy reunites with Annabeth, avoids telling her everything he had meant to say, and instead asks her for the dance they missed at Westover Hall.