Dorian Gray is the subject of a full-length portrait in oil by Basil Hallward, an artist who is impressed and infatuated by Dorian's beauty; he believes that Dorian s beauty is responsible for the new mode in his art as a painter. Through Basil, Dorian meets Lord Henry Wotton, and he soon is enthralled by the aristocrat's hedonistic worldview: that beauty and sensual fulfilment are the only things worth pursuing in life.
Newly understanding that his beauty will fade, Dorian expresses the desire to sell his soul, to ensure that the picture, rather than he, will age and fade. The wish is granted, and Dorian pursues a libertine life of varied and amoral experiences, while staying young and beautiful; all the while his portrait ages and records every bad sin.The Picture of Dorian Gray begins on a beautiful summer day in Victorian era England, where Lord Henry Wotton, an opinionated man, is observing the sensitive artist Basil Hallward painting the portrait of Dorian Gray, a handsome young man who is Basil's ultimate muse. While sitting for the painting, Dorian listens to Lord Henry espousing his hedonistic world view, and begins to think that beauty is the only aspect of life worth pursuing. This prompts Dorian to wish that the painted image of himself would age instead of himself .
Under the hedonist influence of Lord Henry, Dorian fully explores his sensuality. He discovers the actress Sibyl Vane, who performs Shakespeare plays in a dingy, working-class theatre. Dorian approaches and courts her, and soon proposes marriage. The enamoured Sibyl calls him "Prince Charming", and swoons with the happiness of being loved, but her protective brother, James warns that if "Prince Charming" harms her, he will murder Dorian Gray.
Dorian invites Basil and Lord Henry to see Sibyl perform in Romeo and Juliet. Sibyl, too enamoured with Dorian to act, performs poorly, which makes both Basil and Lord Henry think Dorian has fallen in love with Sibyl because of her beauty instead of her acting talent. Embarrassed, Dorian rejects Sibyl, telling her that acting was her beauty; without that, she no longer interests him. On returning home, Dorian notices that the portrait has changed; his wish has come true, and the man in the portrait bears a subtle sneer of cruelty.
Conscience-stricken and lonely, Dorian decides to reconcile with Sibyl, but he is too late, as Lord Henry informs him that Sibyl killed herself by swallowing prussic acid. Dorian then understands that, where his life is headed, lust and good looks shall suffice. Dorian locks the portrait up, and over the following eighteen years, he experiments with every vice, influenced by a morally poisonous French novel that Lord Henry Wotton gave him.
[The narrative does not reveal the title of the French novel, but, at trial, Wilde said that the novel Dorian Gray read was   Rebours ('Against Nature', 1884), by Joris-Karl Huysmans.]
One night, before leaving for Paris, Basil goes to Dorian's house to ask him about rumours of his self-indulgent sensualism. Dorian does not deny his debauchery, and takes Basil to see the portrait. The portrait has become so hideous that Basil is only able to identify it as his work by the signature he affixes to all his portraits. Basil is horrified, and beseeches Dorian to pray for salvation. In anger, Dorian blames his fate on Basil, and stabs him dead. Dorian then calmly blackmails an old friend, the scientist Alan Campbell, into using his knowledge of chemistry to destroy the body of Basil Hallward. Alan later kills himself over the deed.
To escape the guilt of his crime, Dorian goes to an opium den, where James Vane is unknowingly present. James had been seeking vengeance upon Dorian ever since Sibyl killed herself, but had no leads to pursue: the only thing he knew about Dorian was the name Sibyl called him by, "Prince Charming". In the opium den however he hears someone refer to Dorian as "Prince Charming", and he accosts Dorian. Dorian deceives James into believing that he is too young to have known Sibyl, who killed herself eighteen years earlier, as his face is still that of a young man. James relents and releases Dorian, but is then approached by a woman from the opium den who reproaches James for not killing Dorian. She confirms that the man was Dorian Gray and explains that he has not aged in eighteen years. James runs after Dorian, but he has gone.
James then begins to stalk Dorian, causing Dorian to fear for his life. However during a shooting party, one of the hunters accidentally kills James Vane who was lurking in a thicket. On returning to London, Dorian tells Lord Henry that he will be good from then on; his new probity begins with not breaking the heart of the na ve Hetty Merton, his current romantic interest. Dorian wonders if his new-found goodness has reverted the corruption in the picture, but when he looks he sees only an even uglier image of himself. From that, Dorian understands that his true motives for the self-sacrifice of moral reformation were the vanity and curiosity of his quest for new experiences.
Deciding that only full confession will absolve him of wrongdoing, Dorian decides to destroy the last vestige of his conscience, and the only piece of evidence remaining of his crimes the picture. In a rage, he takes the knife with which he murdered Basil Hallward, and stabs the picture. The servants of the house awaken on hearing a cry from the locked room; on the street, passers-by who also heard the cry fetch the police. On entering the locked room, the servants find an unknown old man, stabbed in the heart, his face and figure withered and decrepit. The servants identify the disfigured corpse by the rings on his fingers to belong to their master; beside him is the picture of Dorian Gray, restored to its original beauty.
Output: How is the withered old man identified as Dorian Gray?