Sibyl Vane tells her mother all about her love for Dorian, but only refers to him as "Prince Charming," since she has promised not to disclose his true name to anyone. Mrs Vane is greatly distressed over her daughter's well-being and the family's financial status. She reminds Sibyl that they owe money to Mr Isaacs, the theater owner, but Sibyl doesn't care about anything but her Prince Charming. Mrs Vane is full of affectations, always seeming to behave as if she is on stage.
Sibyl's younger brother James enters, wanting to walk with his sister and bid farewell to his mother, as he is leaving for Australia to become a sailor. James is not an actor, and hates the city and the stage. He is a very serious, stocky young man. It is his hope that he will never have to return to London, and will make enough money to keep his mother and sister from having to act. When Sibyl leaves to prepare for their walk, James urges his mother to protect her. He is very jealous, protective of his sister, and suspicious of the situation, since Sibyl doesn't even seem to know her suitor's name. Mrs Vane reminds her son that Prince Charming is a gentleman, and that it could be a very profitable marriage for the family.
Sibyl returns, and the siblings leave. On their walk, other people stare at them because Sibyl's beauty contrasts with James's stocky, disheveled appearance. Sibyl romanticizes her brother's life as a sailor: she is sure that he will find gold in a distant land, fight off robbers, and rescue a beautiful heiress. James is distressed about his sister's affair, and tells her that he doesn't trust her suitor.
Sibyl defends Dorian, always referring to him as "Prince Charming", and tells James that he will only understand her feelings once he falls in love himself. Sibyl spots Dorian riding by and James runs to see what he looks like, but the carriage drives off. James states, "I wish I had [seen him], for as sure as there is a God in heaven, if he ever does you any wrong, I shall kill him." Sibyl scolds her brother for being bad-tempered, and doesn't take his threat seriously.
After returning home for dinner, James tells his mother that "if this man ever wrongs my sister, I will find out who he is, track him down, and kill him like a dog." The melodrama of the statement and the theatrical manner of its delivery make Mrs Vane admire her son, because she is only truly comfortable when life mimics the theater. James's departure, however, disappoints her, because the potentially heart-jerking farewell "was lost in vulgar details" of haggling with a cab driver.
This is one of the few chapters in the novel that does not focus primarily on Dorian or Lord Henry. Like the preface, and all of the later chapters dealing with James Vane, this chapter was absent from the original version of the novel printed in Lippincott's Monthly. This fact is made apparent from the tone of writing: by introducing three new characters that barely interact with the main players of the story, this chapter seems to deviate from the plot.
However, Wilde does use the Vanes to further explore the complex relationship between life and art. Sibyl and her mother both seem to be stuck in theatrical mentalities. This is most striking in the character of Mrs Vane, who is actually disappointed when the events in her life don't live up to the melodrama of the theater. She appreciates Sibyl's love-stricken outbursts because they are worthy of the stage. When James enters their room, "she mentally elevated her son to the dignity of an audience. She felt sure that the tableau was interesting." She is disappointed with the farewell of her only son, because "It was crude. It reminded her of a bad rehearsal." To Mrs Vane, life has become a shadow of her art.
Sibyl is similarly afflicted, but to a lesser degree. The theatricality of her actions can be attributed to her naivetÃ© and the intensity of her love for Dorian. This love exists in the real world, and thus saves Sibyl from the need to feel that she is constantly in a play. Ironically, this desire to live in the "real world" and experience true love eventually leads to her death.
The threats made by James, which are dismissed by Sibyl as byproducts of the over-zealousness of youth, return to haunt Dorian in the later chapters (specifically chapters 15-18). James comes to represent the inescapable consequences of Dorian's past transgressions. The threats that Sibyl finds so harmless and endearing prove to be earnest declarations of intent.
When Dorian drives by in a carriage, unseen by James but noticed by Sibyl, Wilde is emphasizing the discrepency between their social classes. Dorian rides in an expensive carriage, while the Vanes walk the filthy streets. This discrepency is the source of much of James's rage and frustration, and also Sibyl's tragically idealistic hopes for a better life.