Has anyone here heard some of ? Here's one:

There’s a theory that interprets Ed, Edd and Eddy’s entire cast of kids as all being dead and living in a purgatory of an eternal childhood cycle (originally an eternal summer, but then they started going to school), thusly the complete lack of any adult agents in the purgatory.
They’re are a number of explanations for their deaths, ranging from an explosion due to a gas-leak in the neighborhood to apocalyptic ones such as nuclear explosion or the spread of a deadly disease that killed most of middle-America.
Another theory suggests that the kids in the cul-de-sac are dead children from the neighborhood, each from different times (Johnny and Rolf from the 40’s, Kevin from the 90’s, Naz from the 60’s, Jimmy from the 00’s, and so on).

There's also the Pokemon Comatose theroy, an Animial Crossing one(I don't know ANYTHING about animal crossing) and some others. Discuss and post other Cartoon tales of you can.

Ha. St. Elsewhere parody.

@Tropius: Explain the Animal Crossing one. I can see what you're saying about Ed, Edd, and Eddy, but I think in the later seasons they were actually in a school setting. Yeah, it was after classes ended, but technically they were in school. The lack of parents was annoying... Like Charlie Brown. At least they didn't did go wah-wah-wah off screen.

@Jason
I looked it up, and there are alot theroys about it. One of them, I could get, was that it's a insane asslum.

Not a TV show, but a movie, Lion King seems pretty dark, how Scar kills Mustafa and we see his face when he's dead, Jeez it scares me!

In The Pokemon Black and White Pokedex Volume 2, some of the desriptions about Pokemon are very dark.

Last but not least, Piranha (It scared me to death)!