Raoul considers Christine’s letter, and his emotions flip between pity and anger. He concludes to buy a mask and attend the ball in disguise. Christine—also in a mask—finds Raoul and leads him through the Opera to a private box. On the way, they pass a man dressed as Red Death, and Raoul recognizes the man’s mask as the one from Perros-Guirec.

In the private box, Christine listens for followers, which Raoul mistakes for her protecting her lover. He accosts her for leading him on while loving her Angel of Music, and he mocks her pleas for understanding. When she reveals her changed and unhealthy face, Raoul tries to apologize, but Christine leaves and orders him not to follow.

Raoul wanders the Opera, hoping to confront Red Death. Unsuccessful, he goes to Christine's dressing room to cry. Christine soon arrives, which forces Raoul to hide. To Raoul's surprise, Christine laments for someone named Erik. A distant song emanates from the wall, growing louder until the voice is in the room without a body. Christine happily opens her arms to the voice in front of her mirror. Before Raoul can stop her, a trick of the mirror allows Christine to disappear with the voice.