Harry Potter and the Prisoner of Azkaban - Which Way Again?
When Hermione hits Malfoy the first time, she turns away and then swings around to nail him with her fist. Yet when they go back in time and she and Harry are watching themselves, Hermione is standing in front of Malfoy, doesn't even turn slightly, and punches him.
Actually, you are quite mistaken. She does turn. You see, when Hermoine hits Draco for the first time, she does that half-turn thing. When you see Hermoine in the future looking at her self, the camera doesn't go to Hermoine in the past until she is actually hitting Draco. It is all very simple, but hard to explain.