What happens is the opposite of what was expected, or of what someone planned, in a way that reveals something about the characters or the world of the work.
In The Brothers Karamazov
people love the fall of the righteous man and his disgrace.
What Zosima said in life describes exactly what the monastery does to him after his death. The sentence, said as a general observation, turns into an accusation against those who heard it and now carry it out.
Book VII: Alyosha, the narrator, recalling a phrase that Elder Zosima used to say