Short stories where the tone of writing hides how deeply disturbing it is—at least at first

The first short story that comes to mind is “Where Are You Going, Where Have You Been?” by Joyce Carol Oates. You don’t really expect it to go the way it goes. Maybe even “The Lottery” by Shirley Jackson: you go from wondering what this whole event is all about to realizing the true horror of the lottery.

From casual dialogue and interactions masking dark undertones to conversational narratives that try to hide something unsettling—anything that changes the mood from pleasant/nothing to be concerned about to immediate dread will work. Do you have any suggestions? Also, why do you think they work so well?

by frouzan1967