Henry: some rich society guy who is friends with Basil
Dorian Gray: Basil's subject of obsession with his painting
Sybil Vane: an actress and Dorian's first love (sort of)
James Vane: Sybil's brother
What happens now - a long story: Against Basil's better judgement, he lets Henry meet Dorian who is a handsome youth. Henry and Dorian have tea in Basil's garden where Henry enlightens Dorian on his ideals/views. He expresses how Dorian will not be more beautiful than he is right now and all the wonders of youth that could do anything. They go back inside to see Basil's portrait of Dorian and Basil reveals it as his best artwork yet, his masterpiece. Dorian is unsettled by the likeness and exclaims he would sell his soul to switch places with the painting so he would stay young forever and the portrait would age in his place. Basil gifts the painting to Dorian after turning down Henry's offer to buy it and promising Dorian he will not showcase it.
Dorian decides, after being influenced by Henry's ideals, to live life with the reckless abandon of youth and falls in love with Sibyl Vane, an actress at some lowly theater, because of her acting talent. He tells Henry and Basil about her and that he has proposed marriage. However, when they go to the theater, her acting is horrible and Dorian breaks off the engagement backstage after the performance. She begs him not to, that she will try to be better but that after feeling true lover herself for the first time, she finds it almost impossible to act it with feeling on stage. He storms off and she kills herself by drinking poison.
When Dorian gets home he sees a change in his portrait, a cruel touch to the smirk. The next day, he is pretty sure his wish came true and decides to live a better life so the portrait would change no more and starts by writing letters of apology to Sibyl so he can start his new life by being a good husband to her. Just before he is to send the letters, Henry arrives and tells Dorian the tragic news. Dorian now knows for sure his wish came true and after Sibyl's suicide, he is convinced he will not be able to live a good life and decides not to waste this gift. He is going to live however he wants and do as he pleases. He hides the painting in an old room and takes his servant's key so only he can enter it.
Time passes, Basil and Henry are older men but Dorian hasn't aged a day. He has a bad reputation now and Basil confronts him about the rumors he's heard. Dorian blames his whole life and every sin of his on Basil and shows him the reason, the painting. Basil begs him to pray for forgiveness with him and Dorian in a flash of anger stabs Basil to death. Since no one saw Basil go in with Dorian at 2am, Dorian secures his alibi by locking Basil in the room, walking outside and banging on the door until his servant answers. He pretends that he left his key and is just now getting home asking for the time repeatedly. In the morning, he calls a former friend who despises him now and who is a chemist to his house. He blackmails him with some scandalous information that would destroy him but is never revealed to us readers so he will dispose of Basil's body. The ease of the murder and cover up bother Dorian and he decides to go to an opium den to forget what happened. While there, he sees an old companion and decides he wants to go elsewhere after the man blames Dorian for his state. On his way out, some older lady calls Dorian "Prince Charming" which was an old nickname and the only name Sibyl used for him. A soldier who hears her call him that jumps up and follows Dorian out. Turns out he's Sibyl's brother James Vane who became a sailor, before her suicide and his deployment, he told her if Dorian hurt her, he would hunt him down and kill him.
James follows Dorian into a dark alley, swings him around, points a gun to his head and tells him to make his peace because he is going to die. Through his pleading, Dorian figures out who he is and tells him he is not the person he is looking for that if he walks into the light, he will see he is too young to be the same man. James lets Dorian go and after he gets away, the old woman chastises James saying that was the same man and that he hasn't aged in over 18 years or so. Dorian takes his near-death experience as a sign to live a good life. While entertaining Henry and a duchess, he faints after thinking he saw James looking in through a window. He decides to go on a hunting trip. While in the field, a gentlemen aims to kill a rabbit and Dorian tries to stop him because it is too beautiful to kill. The man shoots anyways when it dashes into a bush and inadvertently shoots and kills James who was hiding in the bush.
Later, Dorian tells Henry about his plan to live a better life and Henry laughs saying he wishes he would either share his secret or switch places with him. He says Dorian's youth serves as proof that he couldn't have done anything too wicked with his life to which Dorian responds he killed Basil. Henry does not believe him much to Dorian's distress. When Dorian returns home, he is upset over James & Henry's claims and loses it in his painting room. He stabs the painting and when his servants break into the room, they find an ugly, old body stabbed in the heart and the beautiful painting of Dorian Gray.