Dorian awakes from a dreamless sleep and gradually remembers the terrible events of the previous night. He writes a letter summoning Alan Campbell, and sends his servant to deliver it. While he is waiting, he distracts himself from his guilt by reading poetry from a book given to him by a man named Adrian Singleton, and reflects on the course of his friendship with Alan Campbell.
The two men first met at a party. Alan was a man of science, a chemist, but the two initially bonded over their shared love of music. Alan "was an extremely clever young man," but "whatever little sense of the beauty of poetry he possessed he had gained entirely from Dorian." For a while the two were inseparable, but for unspecified reasons Alan began leaving parties whenever Dorian showed up and refusing to speak with him or interact with him in any way. Alan withdrew from society almost entirely, immersing himself in his experiments.
The long wait nags at Dorian, but Alan eventually arrives. Dorian speaks cordially, but his guest is cold, curt, and suspicious of his host's motives. Cutting to the chase, Dorian tells him that he needs him to get rid of a dead body, the result of a suicide. Alan refuses and wants nothing to do with the situation - or with Dorian at all, for that matter. Dorian, hoping to win Alan's sympathy, confesses that it was murder, and says that he only needs Alan to pretend to carry out an experiment. It becomes clear that Alan is determined to resist all of Dorian's tactics.
Reluctantly, Dorian turns to blackmail, showing him a letter that he promises to send unless the scientist agrees to help. Alan succumbs to "the disgrace with which he was threatened," and writes a letter for his assistant, detailing the tools to be brought at once to Dorian's house. The tools are delivered, and Dorian dismisses his servant for the evening so that he does not become suspicious.
The two men haul the heavy trunk of tools upstairs. Dorian realizes that for the first time he has forgotten to cover the painting before leaving the attic. He rushes to throw the curtain over it, but before he does so he notices the sickening gleam of red blood on the hands of his doppelganger. Alan arrives with the trunk, locks himself in the attic, and goes to work. Around seven in the evening, the deed is done. Basil's body has been incinerated, and Alan leaves with the words "Let us never see each other again."
Until now, we have heard the names Alan Campbell and Adrian Singleton mentioned on the list of names of those Dorian has corrupted, but this chapter contains the first instance of a face-to-face interaction with one of them. Aside from Sibyl, these two are the only people whose lives Dorian has ruined who actually appear in the book. Once again, the narrator refuses to state the reasons for the bitterness Alan displays towards Dorian, or the content of Dorian's blackmail letter, but these omissions only heighten our sense of how allegedly unspeakable their transgressions must have been. We learn that Alan no longer wishes to show his face in public, and we have learned in earlier chapters that Adrian is likewise ostracized. The likeliest causes for this shame - homosexual encounters - are, however, only tacitly present.
When Wilde himself stood trial for accusations of sodomy in the years following this book's publication, he wrote of "the note of doom that...runs through...Dorian Gray"; it was instances such as these that Wilde was referring to. Wilde revised later editions of the book in an effort to reduce the prominence of the homosexual undertones, but they were too integral an aspect of the interactions between the main characters to be eliminated entirely.
Dorian's cordiality towards Alan when his guest first arrives is a facade. His seeming reluctance to blackmail the man is insincere, an indication that Dorian actually takes pleasure from the manipulative power he holds over Alan. Alan is not fooled by Dorian's pretense of kindness, but has no choice but to comply with his wishes. In this interaction, we witness how refined Dorian's capacity for social persuasion has become during the 18 years glossed over in chapter 11. He has been a good student of Lord Henry, now equalling, or parhaps surpassing, the older man's powers of manipulation.
The poem that Dorian reads while waiting for Alan is significant for several reasons. First, it is from a book given to him by Adrian Singleton. Dorian relies on the gift of a man that he has somehow betrayed for comfort. The lines that he repeats over and over to himself, "Devant une facade rose/ Sur le marbre d'un escalier," are translated as "Upon a red-faced town/ On the marble of a stairway." These lines seem to encapsulate Venice for Dorian, who has visited the city with Basil. Remembering the painter, however, only leads him to remark "Poor Basil! What a horrible way to die!" Dorian is unwilling to openly admit that he is directly responsibile for Basil's death. In fact, Dorian instead blames Basil for the suffering caused by the painting. This is, of course, highly delusional behavior. It would make more sense to blame Lord Henry, his corruptor, but even this would be inaccurate. Dorian himself is responsible for wishing the enchantment into existence. However, the genuine acceptance of responsibility for his misdeeds is well beyond Dorian's ethical capacities at this point.