The group is hired by Sebarial to map the lower levels of Urithiru, keeping anything they find. He also offers Erytl Photrak a deal: he'll sponsor her entry into the Thaylen Merchant Council and contribute to a ship, in exchange for two missions a year on his terms.

While mapping, they're stalked by a powerful Fused who attacks from supernatural darkness. They find a suppressor fabrial that weakens Voidlight users, which helps them kill the Fused. The fight prompts Erytl Photrak to swear her second Dustbringer ideal. Tas-son-Dar also defects to Shallan's side against the Ghostbloods.

Back in Urithiru, Orlan has visions of a Fused invasion led by someone named Raboniel, which she reports to Navani. The group then hunts down and destroys a Midnight Essence, after which Re-Shephir rewards Orlan with an ancient book about her people — triggering her second ideal as well.

Finally, the group travels to Greater Hexi, rescues a healer named Axoq from Ylt's minions, and follows him to the Nightwatcher's Valley. There they witness Ylt asking the Nightwatcher for a weapon capable of killing the Herald Paliah — a wish she grants, with the curse that he must convince someone else to wield it.