Nightmarefuel: Codename: Kids Next Door

And you thought Bubbles was scary when she was angry.

  • The Delightful Children are terrifying when you know who they really are, and what happened to them. They used to be Sector Z, until they were captured by Father himself, and put them through such rigorous torture (or as he puts it, Delightfulization) to the point that's it's quite literally IMPOSSIBLE to turn them back (any attempts are just temporary). To think that such honorable members of the KND have been turned into such monsters is not only scary, but you have to think of what kind of treatment Father put five ten year olds through, not to mention that the torture was so intense that they work as one being.
  • Heinrich, Numbuh Five's nemesis, trying to dunk a live rabbit in molten chocolate. Terrifying. Even worse when he soon after tries to dunk Abigail herself into the molten chocolate. And Heinrich used to WORK WITH Abigail before! And then Heinrich fell into the chocolate and became an eldritch abomination! And finally, the fact that Heinrich is really a pretty little girl!
  • The Crazy Old Cat Lady in her first appearance.
  • Father was pretty scary before his Villain Decay.
    "It appears you just aren't ready for the adult world, Mr. Uno. I believe it was time you were... FIRED!"
  • Grandfather, Father was originally scary, Grandfather takes it to another level. Sure, he's got some humor, but overall, he's just scary. To elaborate, he's capable of turning anyone he touches into a citizombie...which naturally have the same ability as well. He's even capable of zombifying the world in a sense, turning it into a colorless world with tapioca factories for KND treehouses. His reign was implied to have been like one big old time Child Labor sweatshop taken Up to Eleven.
  • The Pirates of the Caribbean parody episode. Somehow, turning into licorice skeletons seems scarier than turning into regular ol' skeletons. And that's not mentioning what happens to them when the sun comes up...
  • The delightfulization process. Can you imagine being permanently brainwashed into being evil?! There's also the fact that you're probably alive and aware throughout the entire ordeal and maybe even afterwards...
  • Numbuh Three when she's pissed. She's just plain scary, especially her appearance. And her anger gives a whole new meaning to Beware the Nice Ones.
    • When she's almost made into a burger and served to a minivan full of sharks. Sounds hilarious? Guess again.
  • The show gets a large portion of its Nightmare Fuel from Fridge Horror and Adult Fear. Adults who enslave their children? Corrupt Corporate Executives that can and WILL kidnap your kids for cheap extraterrestrial labor? Dean Bitterman, the Scary Librarian, and even the Evil Teacher taken Up to Eleven? LICE THAT CAN GROW TO BE THE SIZE OF SMALL CARS? It's a GOOD thing the Kids Next Door is in charge, or the world would be a serious Crapsack World, and NOT JUST FOR THE KIDS...
  • The fourth grade class president shoving the reprogrammed boyfriend helmet onto Lizzie's skull as it fuses with her head!!
  • Operation P.O.P., where kids are being shoved into giant bottles of root beer.
    • Numbuhs One and Four had it worse. They both got shoved into a bottle meant for one person.
  • The Chicken Pox, as in, living chicken heads grow out of your face
  • The Delightful Children From Down The Lane, even without knowing their backstory, they're still creepy regardless especially the episode when one of them pretended to join the KND, after he revealed his true nature and rejoined the Delightful Children, he simply... slid into place *shudder* adding to the fact they talk in unison like a hive-mind, as if the writers were thinking "You know the Children of the Damned? Let's see how far we can emulate that while still keeping a G rating"
  • The episode where Count Spankula turns Numbuh One into a spanking vampire. The entire treehouse is on lockdown til sunrise, it takes place in the middle of the night, and the colors change to a deep red, while the kids are stalked and picked off one by one, without even seeing who is after them.