Chapter fourteen is the aftermath of the Chimera attack in the previous chapter. Because of Echidna and the Chimera, there was a large blast at the top of the Arch in St. Louis, which caused a huge hole. In an effort to escape the two creatures, Percy Jackson jumped out of the Arch to the Mississippi River, which was 630 feet beneath them. Although hitting water at that speed would kill a human instantly, Percy was caught gently by the water with no pain because he is the son of Poseidon. The water put out the fire, which the Chimera had set on his clothes, and it cured the poison the Chimera had put in Percy.
While Percy is experimenting with his ability to make all things beneath the water dry (he is able to light a plastic lighter and set a hamburger wrapper on fire), a mysterious voice tells Percy to thank his father. He does, and then the voice tells him to pick up Riptide (his sword/ballpoint pen). He realizes that the voice was not in his head, so he asks who was there. A moment later, a figure to go with the voice appears, and Percy mistakes her for his mother; she was like a ghost, the color of water, and floating above Riptide. She tells him that she is a messenger for his father, and that he should be brave because his father believes in him; she also tells him that his father wants him to go to the beach at Santa Monica. He asks for more information, but she is too weak since she is so far from the sea, and she vanishes.
Percy then leaves the river and goes to find Grover and Annabeth. They are both relieved to see him and surprised that he survived such a fall. He tells them what happened, and then hears that the police have his name and they suspect him of being involved. As quickly as they can, they head through town, luckily without being seen, until they get to the train, which they use to head towards Santa Monica.