Final answer:
The dramatic irony in "The Story of an Hour" is that Mrs. Mallard dies from shock not out of joy as the doctors say, but from seeing the freedom she just tasted taken away with the return of her supposedly dead husband. This emphasizes the theme of societal suppression of women's desires and independence.
Step-by-step explanation:
The dramatic irony that closes "The Story of an Hour" revolves around the reappearance of Mrs. Mallard's husband, whom she believed to be dead. The ironic twist lies in the fact that Mrs. Mallard has just experienced a quick blossoming of freedom at the presumed death of her husband, only for this freedom to be snuffed out upon his return. In the ultimate and most tragic twist, Mrs. Mallard dies from the shock of seeing her husband alive. The doctors claim she died of "joy that kills," which is ironically contrary to the reader's understanding that her death was actually due to the loss of her newfound independence.
This irony accentuates the story's theme which critiques the repressive nature of institutions, like marriage, and society's expectations on women. Through this lens, the author illustrates how these societal pressures suppress women's natural desires and aspirations, leading to a poignant discussion on the plight of women during the time period in which the story was written. Mrs. Mallard's short-lived hour of freedom represents a powerful expression of human desire to break away from oppressive social norms.