There was an episode or two of Northern Exposure where Shelley Tambo (the smoking-hot blonde waitress) could only sing, not talk, as the result of some head trauma. I forget what season, but the show got gratuitously Felliniesque towards the end, and I think this was an early sign of it.
I Love Lucy, The Brady Bunch and (of course) The Partridge Family incorporated musical bits. There was also that awful Partridge Family spinoff, Getting Together, starring Bobby Sherman and Davy Jones. Speaking of whom… The Monkees!
Skins and Nip/Tuck both had episodes where the characters all sing a song at the end of the season.
Dr. Horrible is all singing.
Viva La Laughlin is all singing.
Voyager has had episode where a character sings as part of the plot (Doctor on math planet, Seven in WWII holo program), but in one particular episode the Doctor sings about the plot (Tuvok getting pon far).
7th Heaven did one, but it was really really really really bad. Really.
Sooner or later every successful series that doesn’t take itself too seriously tries a musical episode. The Buffy episode was quite a bit better than average. It had good music and decent performances. It also advanced at least four major season plotlines, in clever and well-done ways.
Ally McBeal had a few episode which had a LOT of music in it but not a ‘musical’ episode as such. I think every episode must have had at least one song in it.
Well… 7th Heaven certainly wasn’t a great show. But it was, let’s say, the comfort food series of the WB. Something to watch when you don’t want reality creeping in, aren’t in the mood for an all out sitcom, but still want something predominantly positive.
So certainly I wouldn’t expect the musical episode to be as brilliant as the Buffy one. But I thought maybe it would be a bland but mildly fun waste of time, with a small novelty factor. But no, it was painful and torturous.
I seem to recall that the short-lived teen show Popular had a musical season finale which specifically parodied the Buffy musical and in general parodied what the writers considered to be season finale ratings whoring tactics.
Oddly, the great Patinkin does not sing in that episode, as he was no longer a regular by that point and appeared only once all the insanity was over. He sang in many others, though.
