The first sentence of Kate Chopin's short story "The Story of an Hour" clearly warns the reader about Mrs. Mallards weak and feeble nature, caused by what seems to be an external condition.
Knowing that Mrs. Mallard was afflicted with a heart trouble, great care was taken to break to her as gently as possible the news of her husband's death.
Later in the story Chopin offers more details which intrigue the reader; here we have a woman who suffers from heart trouble and yet is described as
young, with a fair, calm face, whose lines bespoke repression and even a certain strength
Why would a woman this mellow be so sick in her heart? Louise Mallard's characterization continues to be described with her eyes now looking "dull" and "fixed" as in a sort of trance that Chopin describes as "intelligent thought". This is indicative of a woman who is transfixed in wonder, but the reader is still not aware that this wonder comes out of the joy of her prospects; for her husband's apparent death is, to Mrs. Mallard, the opening of a door leading to freedom.
In a style that resembles an ongoing train, moving faster and faster, Chopin adds more exhilaration and expression to the emotions that are felt by Mrs. Mallard; these are emotions of joy, excitement, and hope for a future where she can finally "live for herself".
There was a feverish triumph in her eyes, and she carried herself unwittingly like a goddess of Victory.
The ironic and climactic ending unfolds with the shockingly surprising entrance of Brentley Mallard into the home. Not only is he not dead, but he is not even aware that there had been an accident! It is easy to imagine the level of frustration felt by a woman who had just minutes before tasted a much needed sense of freedom. Therefore, it is quite justifiable that, in the end, the poor woman dies of a sudden heart attack. What is more ironic is that the doctor calls Mallard's death as "the joy that kills".