What is a short summary of the Lightning Thief chapter 9?

In Chapter 9 of *The Lightning Thief*, Percy and Annabeth find themselves in the Underworld. They are trying to find the River Styx, where they can cross into the mortal world. They meet Charon, the ferryman who refuses to take them across because they don't have a coin for the passage. After arguing with Charon, they are surprised by the arrival of a mysterious woman who gives them a coin and tells them to follow her. The woman, later revealed to be the goddess Hecate, leads them through the Underworld, revealing its terrifying beauty and the dangers that lurk within. Percy is surprised by the ability of his sword to "breathe" and feels an unexpected connection with the Underworld.