Specifically, of course, musical as a genre - the two I’ve seen are on Buffy and Scrubs, where a story excuse is given to run the whole episode as an old fashioned musical, with torch songs, dance numbers, etc. (I kept waiting for the patter song in Buffy, but unfortunately Giles didn’t get to do one.)
So, are there others? Was Buffy the first? (That’s the first one of this specific pastiche kind of format I can think of.) Are they all good? The funny thing to me is that those two examples are both in later seasons that kind of suck, but the musical episodes are awesome - character driven, etc.
The Dick Van Dyke Show had a Christmas episode in which the cast did a number of musical numbers, the nominal excuse being that this was a Very Special Episode of the Alan Brady Show (although that didn’t explain why Laura Petrie was up there performing with the writers). I;m not sure that’s what you’re looking for.
Of course, every single episode of the 1960s series That’s Life was a musical, as was every episode of Cop Rock. but I suspect you’re looking for musical episodes of normally non-musical shows.
Not at all. Especially The President wore Pearls and My Fair Laddy. If there are any Xena fans around, the was the episode The Bitter Suite. There was also a musical episode of Gilligans Island.
I knew they existed pre-Buffy, but I’m surprised there were so many. That said, I think that show led to something of a prime-time musical renaissance.