The clown that I'm focusing on in this entry, however, is the Tragic Clown from the original Sims, who isn't so much evil as just incredibly obnoxious.
Several years ago, I took a look at the official Sims message board, and it seemed like every other post was either asking how to get the clown to appear, or how to get rid of him. Actually, it's pretty simple, although I'll admit that I'd heard about the clown long before seeing him. A tragic clown painting shows up in the original game, but you need the Livin' Large expansion pack for the joker to put in an appearance. If you have the painting and the moods in the household all fall into the red zone, that's when he shows up. He'll do his best to cheer you up, but not only is he not funny, but he's constantly crying and blowing his nose. And if you think you can trap him in a room with no doors, think again, because he can teleport short distances. (Something tells me THAT'S not a trick you can learn in clown college.) There are two ways to get rid of the pathetic Pagliaccio. One is to improve everyone's mood, which is kind of difficult with the blubbering buffoon hanging around and irritating everyone, but certainly not impossible. The other is to call the Clown Catchers (who actually aren't included in the expansion pack itself, but were available in a free download back in the day), who, for a fee, show up to eject the dejected jester, also taking the painting with them. In a later expansion pack, Hot Date, the clown would occasionally show up downtown. The expansion informs us that the clown's name is Sunny, and that he had a failed fast food chain.
I don't think the Tragic Clown shows up in The Sims 2, although maybe he's in one of the expansions I don't have. I have to wonder if he returns in The Sims 3.