Celeste’s poisoning changes Isla’s purpose: Isla is now fighting not only for Wild Isle and Terra but also for Celeste. Grieving her neglect of Celeste’s realm and fearing Moonling healing cannot save her friend, Isla travels alone to the Place of Mirrors, hoping the sealed Wildling vault might contain ancient remedies capable of drawing out the poison.

Isla tries desperately to open the strange lock by force. She injures her hand, searches the abandoned palace for anything that might fit, and breaks an instrument in the lock, cutting herself further while removing the splinters. By noon, Isla is forced to leave without success, angrier and more determined to punish Cleo, whom Isla blames for Celeste’s condition.

Isla and Oro then return to Moon Isle to search one of the final possible locations for Lightlark’s heart. They enter what first appears to be a tower but is actually an ornate marble palace buried in ice, with its main floor submerged underwater. Oro strips down to avoid being dragged down by whatever lives in the water, and Isla, embarrassed but defiant, follows his lead; their tense exchange exposes Isla’s inexperience and deepens the charged intimacy between them.

Underwater, Isla searches for water lilies whose roots might hide the heart, but a beautiful, scaled night creature invades Isla’s mind and lures her away. Isla briefly forgets her purpose until the beating of the heart returns to her memory. When Isla resists, the creature slashes Isla’s side, drags her under, and nearly drowns her, but Isla uses a hidden dagger to stab the creature in the eye and escape to the stairs.

Oro explains that the creature can shut down a person’s mind, then heals Isla’s wound with his remaining power. The search fails; the heart is not in the submerged palace. Oro reveals the final likely location is deep in Vinderland territory, home to the group that once attacked Isla, and shocks her by explaining they are exiled Wildlings who renounced their power before the curses and eat flesh by choice rather than compulsion.

Oro offers to go alone, but Isla refuses because Celeste, Terra, and their people now depend on her. That night, Oro brings Isla to the castle’s ancient weaponry store, where Isla gathers bows, arrows, knives, throwing stars, and swords. Isla ends the chapter armed and ready to face the former Wildlings who nearly killed her.