Do you remember any scary episodes in non-horror TV shows from the 90s and early 2000s?

I'm talking about something like the Treehouse of Horror Halloween special episodes from The Simpsons, but from other shows. I'm specifically interested in shows that were not usually horror-centered (not the case of Goosebumps or Are You Afraid Of The Dark, for example). I remember 'The Honking', that Futurama episode where Bender becomes a car when exposed to the full moon (but that one was not scary at all).

Did any of those episodes really make you uncomfortable and scared?

For me, I remember that there was an episode from Family Matters where there was a Steve Urkel muppet, and it scared the sh*t out of me as a kid. Maybe it's not the best example, since I don't think the tone of the show changed to a horror story, maybe was just me being a very easily frightened kid...

Can your recall any similar episodes in other shows that gave you the creeps?