Lin studies Petrov’s strange stone at home, distracted by Chana’s accusation that Lin treats Mariam more like a patient than a friend. When Oren Kandel pounds on Lin’s door after midnight, Lin assumes an urgent patient needs her. Oren escorts Lin to the Sault gate, where a Palace carriage waits.

Inside the carriage, Lin finds Mayesh, his robes stained with blood. Mayesh says Prince Conor’s supposed cousin, Kel Anjuman, has been found unconscious and bleeding at Marivent, and that the Palace chirurgeon would likely kill him. Lin resents being pulled into Palace affairs but accepts because her medical oath requires her to treat any patient.

At Marivent, Lin is taken to Prince Conor’s apartments, where Conor is panicked over Kel’s condition. Lin sees that Kel is suffocating because blood is pressing on his heart and lungs. Despite Conor’s suspicion and interference, Lin makes an incision between Kel’s ribs, drains the blood with a reed, and stabilizes Kel’s breathing. Kel wakes briefly, and Lin tells Conor that Kel will live if infection can be prevented.

Conor tries to question Kel immediately, and Kel identifies the attackers as Crawlers while insisting Conor not retaliate because they did not know who he was. Lin notices Kel’s many old scars, his strange calm around pain, and an Ashkar talisman in his hand. When Lin touches it, she feels a sharp pain at her side. She orders Conor out so she can finish treating Kel, then disinfects, cauterizes, numbs, stitches, and bandages his wounds while speaking with him about the divide between nobles, ordinary Castellani, and the Ashkar.

Afterward, Lin tells Conor that Kel is alive and needs rest, but she refuses Conor’s signet ring as payment. Her blunt rejection insults Conor, and Mayesh later tells Lin that Conor has forbidden her from returning to Palace grounds. In the carriage, Lin reveals that she knows Kel is not Conor’s cousin because of his scars and the anokham illusion talisman tying his appearance to Conor. Mayesh makes Lin swear secrecy and tells her that Kel is really Kel Saren, the Prince’s Sword Catcher: a double, bodyguard, and shield known only to House Aurelian.

Back home, Lin reflects on Kel’s origins as an abandoned child and resolves that Conor cannot stop her from treating her patient. She then discovers that Petrov’s stone burned through her pocket and scorched her hip at the moment she touched Kel’s talisman. Remembering the inner whisper, Use me, Lin realizes the stone may have acted or spoken to her, but Petrov is gone and his answers may be lost in the Maze. A closing tale recounts Sorcerer-King Suleman courting Queen Adassa and teaching her the power of Source-Stones, though she refuses to surrender her throne by marrying him.