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Nightmare Fuel: Revolution
In a world that has a worldwide blackout lasting for 15 years, Nightmare Fuel is expected to happen.
The episode "The Night the Lights Went Out in Georgia" has this occur. Aaron and Rachel get attacked by two militia goons. But then, they die suddenly and painfully. It turns out that Jane had intervened and used a gun on them that shoots a microwave beam. That's right, she fried them to death. Those two goons were Asshole Victims who performed Attempted Rape on Rachel, but that was still a brutal way to kill them off. The other thing that made it scary was that the beam from the gun was invisible (which is realistic), so it looked like the goons just magically suffered spontaneous combustion right then and there.
The episode "The Love Boat" has this occur at the end. Grace is at the Tower, and she successfully gets the elevator that can go deeper into the building working again. Mr. Austen, Randall Flynn's goon, suddenly decides to be greedy and go down to level 12 by himself so he can get the power back on and have it all for himself, while Randall is absent. He handcuffs Grace to her chair and smugly goes into the elevator. It goes all the way down...to level 7, and then it just stops. Mr. Austen assumes that Grace is messing with him, but then the camera showing the inside of the elevator suddenly fades to static. Then Grace hears sounds and screaming down there. After a pause, the elevator suddenly goes all the way back up to level 1 and ominous music is playing. Grace is trying to get out of the handcuffs, but before she can, the elevator reaches level 1 and opens. We are not shown what is in the elevator, except for a lot of blood. Grace is shown to be horrified at what she sees. Yes, Mr. Austen is very dead, and we don't even know what happened. At least we now have a possible reason for the elevator being deactivated for all those years...probably to keep something sealed down there. Hopefully whatever it is doesn't get Grace next. An example of Nothing Is Scarier at its finest.
The episode "Clue" has this occur the minute Team Matheson stops at an airstrip to get fuel for the helicopter. The pilot is discovered to be dead suddenly and unexpectedly. Miles assumes that the X-shaped slash on the pilot's throat is the work of Plains Nation residents. The trouble with that assumption is that they're in the middle of nowhere, and they haven't actually encountered anybody. Later, rebel leader Wayne Ramsay is found with his throat slashed and he can only communicate to Miles that one of their number did this to him. What makes this scary is how they're alone, someone is picking them off one by one, and there's a general feeling of it all being too quiet. Later, Nora Clayton is found sprawled out but alive. Several times we're treated to a Through The Eyes Of Madness moment through her eyes, because she got injected with a drug that makes her paranoid, aggressive, and experience blackouts. Another thing that adds to the nightmare aspect is how several characters keep disappearing from other characters' sights, creating a feeling of paranoia and wondering where are they and what are they doing off-screen.
When the power comes back on, all the previously partially-suppressed lightning comes back in a sudden blast of successive bursts. Bass is in the open plain, with nowhere to hide. He must have been crapping bricks!
A guy comes in to get treated and his shirt got melted to his shoulder. We learn he was 30 miles away from Atlanta when the nuke went off.
Everything behind the red door at Titus's compound.
Whatever the "Patriots" are doing in those super-secret compounds. Look at the casual brutality Jason exhibited in killing those soldiers who were out to get him and Tom. Keep in mind he and his opponents had the same training.
Truman tells Gene and Charlie there's been a typhus outbreak. The only way it could have been introduced was through the oranges purposely given to the people of Willoughby, which means that the Patriots plan to purposely exterminate centers of opposition by means of biological warfare. And they don't even care if some of their own soldiers get lost as "collateral damage".
The "Patriots" are programming teenage recruits with beatings, hypnosis, and drugs to the point where reciting an activation code tattooed on the inside of their eyelid leads to them trying to murder as many people as possible and, failing that, killing themselves without hesitation.
Connor is clearly disturbed when he witnesses his father mercilessly slaughter a group of Patriots (most of them children). This is the first time he sees what his actor described as "[Monroe's] Sociopathic tendences..."
Priscilla is effectively a nanite-zombie. There doesn't appear to be any limit on the number of people they could "inhabit" in this way. Talk about creepy...!
Priscilla's dream of being with her daughters starts out as absolutely heartwarming...then the dream is revealed to be the work of the nanites as the images of her daughters deteriorate before her eyes.
The nanites claim to have contacted "3289" people. That's over three thousand people who all had creepy green fireflies show up around them and make them hallucinate dead people.
The nanites deciding to control humanity mentally, and doing so by experimenting on animals, and then on selected human beings, who apparently have no idea they're being forced to sit in a house and do one repetitive thing over and over in a mimicry of normal human activity. And now, they want to control the entire human race and are manipulating former Patriots to once again help plunge North America into war.