On the fifteenth day of the Centennial, Isla grows impatient to search another protected library for the bondbreaker. Because Star Isle did not have it, Isla hopes Sky Isle might, while knowing Moon Isle must wait for the full moon and Sun Isle still has no clear access plan. Isla and Celeste prepare an improvised enchanted hair dye from stolen Wildling ingredients so Isla can pass as a Skyling.

Celeste coats Isla’s hair with the light-blue paste, and the transformation works well enough to risk the mission. Celeste reassures Isla that Isla’s years of sneaking through other realms’ newlands, stealing clothes, and impersonating others have prepared her for this. Isla accepts that, to reach the bondbreaker, Isla must become not only a thief and liar but a fraud.

Isla reaches the bridge to Sky Isle and nearly turns back because the enchanted bridge could collapse if outsiders are barred, killing Isla and dooming Wildling with her. A drunken Skyling man appears behind Isla and assumes Isla is crossing, forcing Isla to proceed. The bridge holds, and Isla enters Sky Isle, a realm of floating rock cities, waterfalls, open halls, and carefree people who seem strangely unworried during the Centennial.

Inside Sky Isle’s open palace, Isla finds the tower library empty and searches for the protected section. When no hidden room appears, Isla realizes the skylight might conceal it. Wearing the essence-imprinted gloves, Isla opens the glass and reveals a moonlit hidden chamber with scrolls and relics, but the bondbreaker is not there.

Disappointed and careless, Isla returns to the Mainland castle without her usual stealth. Cleo spots Isla in Skyling disguise and follows, threatening to expose Isla as an impostor. Isla runs into Grim, begs for help, and Grim makes them both invisible just before Cleo reaches the corridor. Cleo searches but leaves without finding them.

After Grim reveals them again, Isla is shaken by both the danger and Grim’s closeness. Grim teases Isla about changing realms and implies Nightshade offers darker pleasures, which unsettles Isla because Grim can sense Isla’s reaction. Isla reminds herself that freedom and breaking the curses matter above everything, thanks Grim, and flees.