After returning to the castle near dawn, Isla goes straight to Celeste and tells her everything Oro revealed about Lightlark’s heart, despite having promised only not to tell Grim. Celeste is alarmed and distrustful, but Isla sees an opportunity: helping Oro search for the heart may let Isla persuade him to show her the Sun Isle library, where she hopes to find information about the bondbreaker before the ball, when the rulers may legally kill.

The next night, Oro takes Isla to Sky Isle, believing it is her first time there. They enter a cold forest and climb to a valley filled with thousands of purse plants, one of two places where Oro has found an unusual concentration of the plants Isla identified in the Wildling garden. Oro explains that the heart’s power will be unmistakable only at very close range, forcing them to search on foot.

Because Isla has no real Wildling power and cannot rely on sensing the heart, she creates a practical system for searching. She opens purse plants one by one and tears strips from her shirt to mark completed rows. After hours of work, Oro returns to find Isla filthy, exhausted, and wearing a shirt reduced to ribbons; he is horrified, but Isla points out how much ground she has covered.

The next morning, Ella brings sturdier clothing and boots sent by Oro. Isla wears them because gaining Oro’s trust may help her reach the library, though she also wears her crown as a reminder of her own status. Before searching again, Isla tries to force Oro to reveal how he learned about the heart, threatening to stop opening purse plants and taunting him about his secrecy and spreading fatal mark. Oro responds with threatening power, then refuses to answer and dents Isla’s crown in retaliation, deepening their hostility.

Over the next three nights, Oro and Isla search the valley from dusk until shortly before dawn, working from opposite edges toward the center. The labor leaves Isla aching, sleep-deprived, and still not fully recovered from her lingering illness, while Oro also grows tired and frustrated. By the thirty-first day of the Centennial, they meet in the middle and accept that the heart is not there. Isla suppresses her frustration because she still needs Oro and asks where the second location is.