Continuity: By the fireplace, Freddie's shirt changes from unbuttoned to buttoned awfully fast.
Revealing mistakes: You can call Freddie "Lightning" because of the speed he can change his socks. When he and Miranda agree on the four weeks, we can see that in the cellar Freddie has brown socks on. But right after that when he sits down in the garden, his socks are blue.
Revealing mistakes: When Freddie is trying to silence Miranda when she is in the bath, the cones covering her nipples can be clearly seen.