Elide and Manon find Kaltain blocking their escape from Morath’s dungeons. Kaltain warns that guards are already coming and that even if Manon escapes by air, Morath will hunt her and use the Blackbeaks against her. When Manon realizes Kaltain has destroyed the demon in her collar, Kaltain proposes a deception: Elide must trade clothes with Kaltain so Kaltain can pass for the escaped prisoner.

Elide reluctantly gives Kaltain the robe, and Kaltain disguises herself with blood until she resembles Elide. Kaltain cuts into the scarred lump in her arm and removes a glimmering sliver of dark stone, placing it in a scrap of fabric from the cloak Celaena once gave her. Kaltain orders Elide to find Celaena Sardothien, give the shard only to her, and remind her of the promise to punish them all.

Kaltain refuses Elide’s plea to escape with them, saying she has no desire to live after what was done to her and likely cannot survive without the power forced into her. Manon accepts Kaltain’s choice and flees with Elide. Guards then find Kaltain disguised as Elide and take her into the catacombs, where Kaltain understands she has been used as a living gate and a key for the demon-king’s return.

In the catacombs, Kaltain is chained to an altar, but the guards fail to notice her true identity or the wound in her arm. When the red-haired young man enters and recognizes her, Kaltain unleashes her true shadowfire. She burns the room, frees herself, and moves through the catacombs, destroying men, demon princes, monsters, cradles, and the tortured witches who welcome the release.

Meanwhile, Manon carries Elide through the Keep because Elide’s injured leg slows them down. Manon, Asterin, Sorrel, the Thirteen, and Abraxos reach the aerie just ahead of the blast and launch into the sky. Morath explodes behind them; Manon shields Elide from the heat, and when the wyverns recover, a third of Morath lies in ruins, including the catacombs where monsters were bred and witches were tortured.