Season 1 Episode 23, "The Night of the Two-Legged Buffalo", in the scene where Artemus arrives at the spa disguised as the prince.

At the beginning of the scene, the camera is zoomed in on the mantel clock, showing the spa manager with clock key in hand, supposedly winding the timepiece. But it's also close enough to be completely obvious that not only isn't he actually winding the clock, but the key is too large for the clock and he's just moving the key around in front of the hole.

The foley artists did a nice job of throwing in some winding sounds, but it's completely silly to have zoomed in that close under the circumstances.