The trio enter the Underworld and cross the River Styx. Persephone takes them to Hades. Percy tries to explain to Hades that he did not steal the bolt. During a resulting chaos, Percy drops his shield, whose handle conceals the missing master bolt, which Hades takes. However, the trio manage to get it back before escaping the Underworld with the rescued Sally, forced to leave Grover behind, in Persephone's "care", as they only had three pearls. They are transported to the top of the Empire State Building, which they learn is the entrance to Olympus. They are confronted by Luke, who reveals himself to have been the real lightning thief. Explaining his hope for new rulers to take over Olympus, he explains that he had hoped that the trio would not escape the Underworld alive. He steals the bolt from Percy and the two fight. After using his water powers to get rid of Luke, Percy arrives in Olympus, where he presents the retrieved bolt, and reveals the truth about Luke. Poseidon explains to Percy the reason why they could not know each other during Percy's childhood, but expresses his love for his son. Percy also requests that Zeus retrieve Grover from the Underworld, to which the god agrees. Percy returns to Camp Half-Blood, where he continues his training, ending the movie in the midst of a clash with Annabeth. After the end credits, a scene shows Sally forcing Gabe out of their apartment and he reads a note on the fridge from Percy that says not to open the fridge. Gabe destroys the lock on the refrigerator and as he opens it, Medusa stares right back at him, and the scene goes black while a crackling noise is heard, showing that Gabe has been turned to stone.