Dorian is annoyed with Sybil and tells her that he cannot see her anymore. Abruptly, he leaves. Dorian wanders the streets until near dawn and then returns home. Passing through his library toward his bedroom, he notices the portrait that Basil painted of him. He is startled and puzzled, but he goes on into his bedroom. He begins to undress but pauses and returns to the library to look at the portrait. To Dorian, the face in the portrait has slightly changed, taking on a look of cruelty around the mouth. Going to the window, he sees a bright dawn. He looks again at the painting. The "lines of cruelty round the mouth" are still there, even more clearly than before. Looking at his reflection in a mirror, Dorian looks fresh and youthful. Suddenly he recalls the wish he earlier made at Basil's studio, that he might remain the same while the picture took on the "lines of suffering and thought," the various signs of corruption and age that Dorian's life might bring him. He thinks that such a wish could never be fulfilled. Surely it is impossible.
Still, there are the cruel lines about the mouth in the portrait. Dorian begins to wonder if he really has been cruel to Sibyl. However, he convinces himself that he is not to blame for the situation. Sibyl is to blame because she disappointed him and made him endure the three painful hours of her terrible performance. Eventually, he convinces himself that Sibyl hadn't really loved him, and he concludes that he needn't be concerned about her at all.
Dorian is more concerned about the changed portrait than with Sibyl. It occurs to Dorian that every sin he commits will be reflected in the face on the canvas. He vows never to sin again so that the painting, like himself, will never change. He vows to use the portrait as his conscience; the danger of hurting the portrait will keep him from committing sins. He will refuse to see Lord Henry or at least will ignore Lord Henry's "subtle poisonous theories." He will return to Sibyl, apologize, and marry her. He pulls a screen in front of the painting and walks outside. The chapter ends as Dorian repeats Sibyl's name into the dawn.
