Nico, Will, and Bob face an army of monsters made up of Nyx’s children. When Nico won’t agree to give his life over willingly, she orders them to attack. Will and Nico work together again, with Will infusing Nico’s sword with his song. Though they and Bob can defeat the monsters, nothing affects Nyx.

Enraged by Nyx tormenting Nico, Will releases a burst of light that hits her wing and makes her scream in pain. Nyx vows that Nico will never return to “a world you don’t belong in” (392). She wants to keep him in Tartarus forever.

Bob and Small Bob attack Nyx in her chariot, distracting her. Will becomes transfixed by her Mansion of Night, which is made up of insects, but eye contact with Nico rescues him from his trance. They notice that none of Nyx’s children fight against them.

Someone sets the Mansion of Night on fire. Bob, Small Bob, Nico, and Will use the opportunity to run away. They pass over Chaos but find that Nyx’s garden has moved: It’s now over where the rivers of the Underworld meet.

Nyx catches up with them, telling Bob he cannot escape his identity as Iapetus.