Irony is the juxtaposition of two incongruous or unexpected elements. In "The Story of an Hour," Louise Mallard is said to have "heart trouble," although I do not believe we are ever told precisely what kind of heart trouble this is supposed to be. This heart trouble, though, is of concern when Mr. Mallard is supposed to have been killed in a railway accident because Louise's sister, Josephine, and a family friend, Richards, worry that the shock of this news might kill Mrs. Mallard. Because this is the reader's expectation, too, the first irony in the story is that Louise retreats to her room, not in shock, but in joy at the freedom her husband's death will bring her. Her heart not only does not fail her, but it could reasonably said that her heart is singing. The second irony occurs when it turns out that her husband did not die in a railway accident. He returns home, alive and well. So instead of being shocked at her husband's death, Louise is shocked at his being alive, shocked at the loss of freedom she had so briefly glimpsed. It is this shock that kills her. In each instance, we have an incongruous, unexpected reaction to Mr. Mallard's "death" and his actually being alive.