Meryn Cooper, a twenty-three-year-old underground fighter known as the "Alleycat of the Eastern Quarter," wins a brutal fight in an emberwine warehouse in the Southern Quarter of the royal city of Sturmfrost. She deliberately feigns weakness to lure her larger male opponent into overconfidence before taking him down with a series of calculated strikes, forcing him to yield. Her trainer and neighbor Igor pays her eight silvers in winnings—enough to cover two weeks of her mother's medicine from the apothecary, whose prices have risen because ingredients are hard to acquire near the war front against the Siphons.

After the fight, Meryn reunites with her boyfriend Lee, a castle messenger who has been her partner for over a year. He tends to her forehead wound as part of their post-fight ritual. They met when Lee saved Meryn's younger sister Saela from a runaway horse in the market. A drunk man who lost money betting against Meryn threatens her with a knife, but she disarms him effortlessly and sends him fleeing. As Meryn and Lee settle in together, Igor arrives with urgent news: another child has gone missing from the Eastern Quarter—a girl around ten years old with dark hair and hazel eyes, a description that matches Meryn's sister Saela.

Terrified, Meryn sprints from the Southern Quarter through back alleys to Eastern, a journey she covers in roughly fifteen minutes. She passes through the impoverished neighborhoods under the shadow of King Cyril's castle. In the Eastern Quarter's market square, she finds Mrs. Sawyer wailing over her missing daughter Leesa, one of Saela's school friends. The missing girl is the latest victim of kidnappers the community calls "Nabbers," who never return the children they take.

Relieved but shaken, Meryn heads home. Her mother, who suffers from severe delusions and doesn't recognize Meryn, mistakes her for someone named "Lumina" and rambles about "the twins." Meryn calms her, administers her medicine, and puts her to bed. She then checks on Saela, who has locked herself in their shared room as instructed. Watching her sleeping sister—who resembles their father, killed in the war—Meryn makes a fierce vow to protect Saela and resolves that if no one else will stop the child disappearances, she will do it herself.