The hippocampi carry Percy, Annabeth, Clarisse, Grover, and Tyson as far as Miami, then refuse to go closer because of the polluted, human-filled waters. Once ashore, the group realizes ten days have passed while they were away, which means Thalia's tree may be close to dying. Clarisse panics because they are far from camp, out of money, and still responsible for getting the Golden Fleece home.

Percy asks Clarisse to repeat her prophecy and realizes its final line means Clarisse must return by air alone, but only after receiving help from friends. Tyson reveals he saved Hermes's bag of cash from the wreck, giving them enough money for one plane ticket. Percy gives Clarisse the Fleece and the money, tells her the quest is hers, and sends her to the airport despite Annabeth's fears that he is trusting the camp's fate to the wrong person.

As soon as Clarisse leaves, Luke ambushes Percy and the others on the dock with his bear-like servants and forces them aboard the Princess Andromeda. Luke demands the Fleece, and Percy tells him Clarisse already has it. Luke loses his composure, orders one of his servants to prepare a flying mount so he can chase Clarisse, and reveals how badly Percy has disrupted his plan.

Seeing Luke enraged, Percy uses the ship's pool and fountain spray to create an Iris-message. He taunts Luke into talking, and Luke openly admits that he poisoned Thalia's tree with elder python venom, that Chiron was innocent, and that he intended to use the Golden Fleece to help restore Kronos before allowing it back to camp. Percy keeps questioning Luke specifically so the camp can hear the confession.

The Iris-message appears before Dionysus, Tantalus, and the campers in the dining pavilion. Dionysus accepts that Chiron was wrongly blamed and says he will reinstate him as activities director. Tantalus is dismissed and sent back to the Underworld just as he finally manages to grab food, and the campers cheer. Luke destroys the Iris-message, but the damage is done, and he turns on Percy with open hatred.

Luke declares that Percy is an unreliable weapon who needs to be replaced. More of Luke's warriors swarm onto the deck and surround Percy, Annabeth, Grover, and Tyson with spears. The chapter ends with Luke promising that Percy and his friends will never leave the ship alive.