A moment of verbal irony occurs when Stanley picks up and inspects the bottle of whiskey that Blanche has been drinking from after arriving in New Orleans. As he holds the bottle up to the light, he comments:
STANLEY: Liquor goes fast in hot weather.
[He holds the bottle to the light to observe its depletion]
This statement, while seemingly innocuous, actually carries some significant weight under the circumstances. Stanley’s remark is verbally ironic because both he and Blanche understand the true implication of his words. He knows—and she knows he knows—that Blanche has been drinking heavily. Yet, at this early stage they are both still willing to engage in pretending the liquor disappearing is a surprising phenomenon of the hot weather. They can laugh about it together without acknowledging what they both know is really going on. Despite her attempts to maintain an image of delicate propriety, Stanley is warning Blanche that he isn’t fooled for a moment.
Stanley uses this observation to subtly communicate to Blanche that he sees through her attempts to flirt and deceive. As the play progresses, Stanley uses moments like this to subtly warn her that he’s onto her. He becomes less and less subtle as time passes, which shows his increasing comfortableness with asserting dominance over Blanche.
The journey Blanche takes to get to Stanley and Stella's apartment when she first arrives in New Orleans is full of allusions to Greek mythology. These allusions create situational irony for the audience, as they imply Blanche is headed for heaven when she certainly isn't. She tells Eunice and the woman sitting outside the Elysian Fields house that:
BLANCHE: They told me to take a street-car named Desire, and then transfer to one called Cemeteries and ride six blocks and get off at—Elysian Fields!
Tennessee Williams named these streetcars after real conveyances in New Orleans—the streetcar which ran through New Orleans’s French Quarter really was named “Desire." Streetcars were a very popular means of getting around in the mid-20th century, meaning that "Desire" would have been a well-known cultural touchstone for New Orleans locals at this time. “Desire” would also have been deeply associated with the lifestyle and the community of the French Quarter, one of the city’s most notorious and historic neighborhoods. In order to get to the Kowalskis’s place, Blanche recounts that she had to take “Desire” from “Cemeteries” to “Elysian Fields.” In addition to referring to real things in New Orleans, these names all refer to the afterlife in Greek mythology.
In Greek legend, the Elysian Fields are the final resting place of the heroic and virtuous. They are a place of eternal reward and happiness that people favored by the gods can reach after they die. Blanche has taken a symbolic journey through death in this scene. After her life at Belle Reve and in Laurel ends, she starts her journey to the Kowalskis with “Desire.” "Desire" is both the streetcar which takes her to Stella’s apartment, and the driving force behind all of her real-life issues. She passes through “Cemeteries” to reach “Elysian Fields," which optimistically implies that Blanche has entered a sort of heaven that will end her suffering.
All of these references, though, are full of situational irony. The “Desire” which drives the actions of all the characters in this play, certainly hasn’t conveyed Blanche to heaven. Blanche's arrival at Elysian Fields, which to the ancient Greeks would represent a heavenly reward, is far from a paradise. Instead, she finds herself in a neighborhood that she finds to be dirty and frightening, and her sister is living in a way Blanche thinks is unbearable. Rather than being a safe place for her to land after she loses everything, coming to “Elysian Fields” in New Orleans only makes Blanche miserable.
During the interaction in Scene 2 where she’s being interrogated about the Belle Reve papers, Blanche teasingly (and ironically) “admits” to her tendency to deceive people. She does so by making a general statement about how women behave:
BLANCHE: I know I fib a good deal. After all, a woman's charm is fifty percent illusion.
Blanche represents an outdated version of the “Southern belle” archetype, a trope of delicate, embattled femininity that invokes the cultural norms of the pre-emancipation South. The “Southern belle” is a genteel, feminine ideal associated with 19th-century gender roles. She is often depicted as graceful, well-mannered, and devoted to modesty and etiquette. This archetype romanticizes a bygone era of plantation life, one in which women had little power and were valued primarily as mothers and ornaments. Being “charming” was a way of surviving in a world which devalued their intelligence.
Blanche, however, is not in either the social or the physical condition to rely on the way she’s been taught to behave. Acting like a “belle” is all she’s got, so her “charm” relies heavily on creating illusions. In fact, these “fibs” make up much more than the “fifty percent” of her appeal she mentions. She knows she’s aging and is not as attractive as she once was to men. The statement she makes here is intended to disarm Stanley, whom she already suspects isn’t amused by her. She knows what she’s saying isn’t going to provoke a response based on its truth. Her comment seeks to provoke a reaction: she wants him to challenge her claim that her charms are based on lies. She’s startled and disoriented when Stanley agrees with her. Because her relationships with men are based on manipulation, when this “Southern belle’s” tactics don’t work, she’s unsure how to proceed.
In an example of dramatic irony, Stella tells Blanche that Stanley’s violence is worth it to her, implying that this is the case because she's a physical, sexual person like her husband:
STELLA: But there are things that happen between a man and a woman in the dark—that sort of make everything else seem—unimportant
Stella's confession to Blanche about her relationship with Stanley reveals her own knowledge of the open secret in her marriage: it’s based on physical compatibility and nothing else. The dramatic irony in Stella's statement lies in her juxtaposition of "darkness" with her physical interactions with Stanley. For Stella, the physical and sexual aspects of her relationship with Stanley, which occur "in the dark," justify and overshadow his violent behavior. The audience, though, can see that Stella and Stanley's marriage is the opposite of how Stella describes it: the violence that happens "in the dark" is what overshadows "everything else" about their relationship, rather than everything else overshadowing the violence. In this sense, they understand the misguidedness of Stella's words in a way that she herself does not.
Deepening this irony is the fact that when these two characters revert to the primal state of sex, they refer to it as “getting the colored lights going.” In this sense, Stella and Stanley are never really “in the dark” when they’re alone together. When they’re forced to communicate with words is the only time they struggle, and in this way, they're in the shadows when they talk and in the light when they can touch. Because of this, and because she's not a particularly deep or thoughtful woman, the way Stella enjoys sex with her husband makes other concerns seem trivial.
This contrasts sharply with Blanche's association of darkness with comforting deception. Blanche is all interior thoughts, and she views darkness as a means to hide the truth. When Stella refers to “darkness” here, however, she’s not really talking about an absence of light. She means privacy, which is where her marriage functions best. By asserting that the physical connection she shares with Stanley makes everything else unimportant, she is, in a way, convincing herself that his violence is worth the pain. The dramatic irony of this self-deception is evident to the audience and to Blanche, but Stella can’t see it.
In the final act of the play, Blanche's interaction with the doctor who comes to take her to the mental hospital is full of dramatic irony. As she is being led away, Blanche murmurs:
BLANCHE: Whoever you are—I have always depended on the kindness of strangers
The dramatic irony here stems from the reality of Blanche’s situation. While Blanche claims to have always relied on the “kindness of strangers,” it is precisely this delusional reliance that has led to her downfall. Blanche struggles to do anything alone. Therefore, her dependence on others for emotional and financial support has left her exposed to manipulation and betrayal. She certainly got this from “strangers,” but she was betrayed most notably by her brother-in-law, whose cruelty and sexual assault directly result in her being sent away.
Blanche's statement is also ironic because the “strangers” she now depends on—the doctor and the hospital staff—are not rescuing her but institutionalizing her. As Blanche loses her grip on reality, Stanley uses his position as head of their household to seal her fate. In the end, he makes the decision for her about where the “dark march” of her path to the future will lead. It’s a decision facilitated by Stanley’s unkindness and Blanche's own misguided choices, but one that also partially stems from her deliberate, stubborn refusal to accept change.