They go upstairs and Dorian shows Basil the picture. Basil is horrified. He wonders who has made the hideous changes. Why has the painting altered? Dorian explains what has happened, and Basil, shocked, says that Dorian must be even worse than his enemies say he is. He is deeply upset and urges Dorian to pray. Dorian says it is too late. Feeling a sudden rush of hatred for the painter, he picks up a knife and stabs him to death. He hides Basils coat and bag. He thinks no one will discover the crime, since everyone will believe that Basil is in Paris. At two oclock in the morning, he goes outside the house, then rings the bell. His valet opens the door, and Dorian tells him he forgot his latch-key (thus giving himself an alibi, should he need it). He then goes to the library and looks up the address of a man he needs to contact.
He writes a letter to Alan Campbell and gets his valet to deliver it. The two men had been great friends five years ago, but the friendship had come to a sudden end. Campbell is an expert in chemistry, and when he arrives, Dorian asks him to destroy Basils corpse so that no trace of it remains. He says it was a case of suicide. At first, Campbell refuses. Then Dorian confesses that he murdered the man. Campbell says he will not inform on Dorian, but he will do nothing to help him. Dorian begs him to do it, reminding Campbell that they were friends once. Dorian then blackmails him. He writes a letter to someone and shows it to Campbell, saying that if Campbell does not agree to do what Dorian asks, he will send the letter. Campbell feels he now has no choice, so he reluctantly agrees. Dorian sends his servant to collect some chemicals from Campbells laboratory, and when he returns, Campbell begins his work, which takes him five hours. After he leaves, there is a smell of nitric acid in the room where the corpse lay, but no trace of the body.
That night Dorian goes out to a party at Lady Narboroughs as if nothing had happened. He finds the party tedious until Henry arrives. Henry entertains the other guests with his usual cynical witticisms. Dorian leaves the party early; the feeling of terror he had tried to stifle comes back to him. When he gets home he immediately burns Basils bag and coat. At midnight he goes out, and takes a horse-drawn cab to a location about an hours drive away.
Basil once more represents the voice of conscience and morality. As such it is no wonder that Dorian, who cannot bear to look at the picture, cannot bear to have Basil hold a mirror up to his own character. Dorians killing of Basil, and his reduction of the corpse to ashes, shows how he still wants to live without consequences; he must completely annihilate anything that reminds him of his responsibilities as a human being.
Those readers who see the novel as a battle between good and evil have plenty of ammunition in these chapters, since Basil does nothing to deserve his fate (except perhaps being unfortunate enough to meet Dorian in the first place), and Dorian has become a murderer without remorse. He even resorts to blackmail in order to get rid of the evidence.
Chapter 14 shows that now, even art is failing Dorian. He tries to escape from the memory of the murder he has committed by immersing himself in a book of poetry. But he quickly comes upon the description of the hand of a murderer named Lacenaire, and this reminds him of what his own hands have done. He perseveres, and immerses himself in the exquisite poems, but is it not enough to prevent a “horrible fit of terror” from coming upon him as he wonders what will happen if he is unable to dispose of the corpse. Real life is pressing in on him, and there is nothing he can do to prevent it. Chapter 16 will reveal further how Dorian has been forced to renounce his earlier ideals.