- "Exit Wounds" has Jack being Buried Alive in the earth. Because he can't die permanently, he's locked in a constant cycle of death and reviving, awakening only long enough to choke and suffocate under the weight of six feet of earth crushing his entire body. For almost 2000 years. How he manages to remain sane after this ordeal is never explained.
- Owen's final "death" in that episode. He's sealed in a room that slowly floods with nuclear radiation, which dissolves his flesh on contact — and because he's undead, he's forced to remain conscious the entire time, watching as his body disintegrates.
- "Countrycide". Not only are the monsters particularly demonic and frightening...they're human. Enough said.
- Gwen gets filled with buckshot by a panicking captive of the villagers. A few minutes later, we are treated to a HORRIFIC shot of Gwen's waist looking like swiss cheese, complete with Owen plucking out the pellets. Happy retching.
- In the end, Gwen demands that the village ringleader tell her why he helped murder and cannibalize hundreds of people. His response? "Cos it makes...me...happy."
- The "fairies" from "Small Worlds". There's no way to stop them...
- Especially the ending with the creepy music/whispering/singing, the image popping up on the screen by itself, and Gwen zooming in to see Jasmine as one of the fairies.
- "Adrift". Particularly the description of what happened to Jonah overlaying the primal screaming.
- "Adam" had a TON of Nightmare Fuel. Just something about Ianto shrieking and weeping because Adam brutally mind raped him into thinking he's a psychopathic killer is chilling.
- "And I liked it..." OH GOD.
- The very idea that a stranger could re-write your entire personality just by altering a few select memories. It's Mind Rape in the most literal sense of the term. And you'd never even know anything was amiss until it was too late.
- ''What were you hoping for? That I'd say a few nice words... That I'd be grateful...'' Oh yeah, and this line is said in a creepy low voice. BY IANTO!
- The Night Travellers of "From Out of the Rain" are just creepy as all hell.
- From "Ghost Machine": It's 1941. You are an 8 year old who just got transported to Cardiff while the Germans are bombing the everloving shit out of you. You said farewell to your mother and sister, not knowing that you will never see them again. Due to a paper error you are left stranded all alone on a train station for a whole night. An 8 year old, all alone, spending the night aimlessly wandering around a train station, completely lost, trying to find someone. You don't.
- The alien monster/parasite that was feeding on Katie's brain in Owen's backstory. Just seeing it latched on her brain like that...
Nightmare Fuel / Torchwood
As a Darker and Edgier spinoff of Doctor Who, it's inevitable that Torchwood would have its own share of Nightmare Fuel. Miracle Day's Nightmare Fuel goes here. Torchwood: Children of Earth's Nightmare Fuel goes here.