The episode: “A Day at the Fair,” the short in front of “Code Name: Diamond Head,” ep. 608
The riff: Spoken in a tone imitating the short’s narrator as “Brother Bob” peruses an exhibit on butterflies and moths.
The explanation: Only a few days after a joke about “Jame Gumb” from “Silence of the Lambs,” here’s another joke about the same character. In the book and the film, Gumb/Buffalo Bill, the killer, puts Death’s Head Moths in the throats of his victims as a symbol of the metamorphosis he is trying to undergo himself.
Novelty factor: Weird coincidence having these jokes show up within a week of one another. As I said before, I’ve read the book and love the movie, so this was obvious to me.