Nightmare Fuel / The Avengers

The British TV series

  • "The House that Jack built": Emma Peel is trapped in a computerized / automated house Professor Keller specially designed to drive her insane or drive her to commit suicide by gas chamber. The computer designed to answer to her has a creepy voice also.
  • Tara King's situation in the climax of "The Curious Case of the Countless Clues": Steed phones her to warn her that two men are coming to kill her and that he's on his way, except that Tara's in a wheelchair due to a busted up ankle, and realizes that her back door is unlocked. Desperate, she climes up her stairs to lock the door, and just in time too.

The Marvel Cinematic Universe film

See here.

The comics

  • The "Under Siege" storyline had Zemo trying to break Captain America by destroying his mementos and torturing his friends, letting the savage Mr. Hyde loose on Jarvis. What happens is entirely off-panel, but the sound effects, dialogue, and expressions say it all.
    Black Knight: How could any man do such a thing... and laugh?
  • Being replaced by a Skrull. You can come back years later and everything you know has changed. Your friends and people you have dated might be dead. The Skrulls don't just steal someone's image, they steal their entire lives, sometimes ruining them in the process.
    • Mockingbird and Spider-Woman's experience are particularly terrifying because, not only was Mockingbird gone for three years, she was hunted by Skrulls after she saw through their tricks, with one of them impersonating Clint while he hunted her. She eventually snapped and killed him. Spider-Woman came back to discover that nobody trusted her after Veranke used her face.
    • The experience of Hank Pym (Ant-Man 1) isn't much happier; he returns to find out that his Skrull doppelganger seduced and impregnated Tigra, a fellow Avenger he'd actually had a crush on. Fortunately, Marvel decided to throw him a bone after years of abusing him over that one time he accidentally smacked Janet and instead things ended up working out nicely, but still, that's really a horrifying scenario in so many ways...