The Night of the Egyptian Queen - S4-E8
Continuity mistake: The first shot of West's eyes, after the opening credits, shows them to be a bit different than usual - as if they had an allergic reaction to something. The second, third, and fourth shots show the eyes back to normal, but the shot of him walking the princess to the door shows a very puffy faced West. After walking her to the door when he turns around, West is back to looking like his typical self for the rest of this episode.