Ophelia returns to the hidden room to study the carving of Gabriel’s name without getting hurt again. She finds no magical reaction from either the words or her locket, but she notices that the scratched-out writing above the carving may have begun with a T, which makes her think of her mother. That possibility overwhelms her, and she breaks down crying for her mother, her fractured bond with Genevieve, the father she never knew, and the softer version of herself that Phantasma has already stripped away. After falling asleep there, she wakes by candlelight and manages to discover the hidden mechanism that turns the shelf and lets her escape back into the library on her own.

In the library, Sinclair appears in darkness and smoke and claims he wants to offer Ophelia harmless fun rather than threaten her. When he asks for her most frivolous fantasy, Ophelia briefly imagines a quiet domestic scene with Blackwell before blurting out a safer answer: she wants to attend a grand ball. Sinclair conjures an opulent ballroom around her, fills it with music and dancers, transforms her nightgown into a lavish ruby-and-gold gown, and leads her in a waltz. He uses the spectacle to show how much power he has and to tempt her toward trusting him, but Ophelia refuses to make any deal with a Devil and insists Blackwell’s bargain is different because Blackwell is helping her find Genevieve.

When Ophelia presses Sinclair about his hatred of Blackwell, Sinclair finally explains his motive. He reveals that most of Phantasma’s rulers are there by choice, but he and the manor’s creator, Salemaestrus, are not. According to Sinclair, Salemaestrus is the Prince of the Devils, punished by his father, the King of the Devils, after choosing his lover over his father; the lover was killed, and Salemaestrus was condemned to run Phantasma indefinitely. Sinclair says he was punished as well because he helped hide that lover. He also claims Blackwell repeatedly sabotaged his attempts to escape, which is why Sinclair wants Ophelia to forfeit: if she loses, Blackwell remains trapped too.

After revealing his grudge, Sinclair vanishes and leaves Ophelia imprisoned inside the illusion. She cannot find an exit, and when she repeatedly summons Blackwell, he does not answer. The ballroom then becomes more dangerous as a procession of beautiful strangers keeps drawing her into dance after dance, wearing down her body and fogging her mind until time blurs and exhaustion takes over. Blackwell finally appears, furious, and realizes Ophelia is still seeing the false ballroom rather than reality. He throws her over his shoulder, walks straight through the wall she thinks is solid, and the illusion shatters as the return to reality hits Ophelia with sudden, violent pain.