The episode: “Robot Holocaust,” ep. 110 (Note: I once saw the non-MST3k version of this movie and it’s pretty funny on its own. Also, it’s funny to see where they cut out the original film’s nudity.)
The riff: Sung by Joel as lilting music plays and a ragtag band of human survivors travel across the really crappy-looking “wastelands.” Joel plays air violin at the same time.
The explanation: The music clearly reminded them of the opening of the song “Stranger in Paradise” from the 1953 Broadway musical “Kismet.” The show, which won the 1954 Tony Award for best musical, is set in the magical old Baghdad of “Arabian Nights” and features actual Muslim characters who would no doubt ignite some sort of insane protest if it was staged today. The actual song was originally a lover’s duet between a girl and the young caliph/king of Baghdad, but it later became more known as a solo male song. The most famous recording was by Tony Bennett, but versions by Tony Martin, Bing Crosby and Four Aces were also successful.
Novelty factor: That’s a big zilcho as far as my comprehension is concerned. I think we’ve pretty much established that I don’t know vintage musical theater very well at this point.