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Nightmare Fuel: The Thing (1982)
To provide due warning to anyone now thinking about seeing this movie, it has Body Horror and Paranoia Fuel out of, and providing, your worst nightmares.
The part where after eating a man's arms with a mouth in its chest, one of the monsters pulls its own head away from its flaming body, after which it (the head) then sprouts legs and eye-stalks and tries to scuttle out the door.
And let's not forget to mention the horrific, inhuman wailing the creature's making the entire time. It's pretty much the icing on the nightmare/nausea cake.
The blood test is one of the greatest jumps of all time. Especially great is how we're made to expect one of two characters is the thing. The guy administering the test is still haranguing them, casually putting the wire to the blood of some guy we barely even remember WHEN IT FUCKING EXPLODES. The blood screeches, and it's the most hideous sound.
The FX men made a little inflatable monster head and neck, which jumps up out of a petri dish held by a false arm the actor wore for that shot. Freeze-frame it. The editing and performance-matching quality here is frankly amazing.
The scene where a guy begins to go into convulsions as he transforms into a Thing, with two other guys flailing and screaming bloody murder because they've been tied together with him.
The burned and twisted biological rejects frozen in expressions of abject suffering, the sickening digestive sequences, the emergence of the Thing from its host, and, of course, the blood test.
The kennel scene. If the charred remains of the merged-heads creature didn't clue you in, the dog creature really hammers home just how alien the Thing is. This is not only due to the appearance of the monster itself, but the sound effects as well (see below).
According to the commentary track featuring John Carpenter, the dog was not prompted for any of the behavior that's so damn creepy (pausing as if to listen for anyone who might discover it, the slow and deliberate walk, and as mentioned above, the intent look on its face). They only trained it to hit its marks on set — the creepiness is all-natural. That's because the dog is actually half-wolf. That standing still and staring is it getting spooked by something, while well trained the actors were genuinely scared of it.
What really made the kennel scene stood out was that when the dog started to transform one of the dogs in the kennel went from aggressive to wanting to get out. Seeing one of them desperately trying to claw and bite at the metal fence just to escape the fate the other dogs received was not only creepy but unsettling.
Although the body horror elements are still incredibly creepy, as well as the paranoia, the sound effects are also pretty nightmare-inducing.
Take for example the scene right before the kennel, when MacReady grabs a beer in the fridge... in the background you hear weird rumbling monster sounds, and then you hear that awful high-pitched dog yelping/barking/squealing. MacReady slams on the fire alarm (which puts you into panic mode).
THEN the scene switches to Clark waiting nervously in the hall, and you hear one of THE MOST god-awfully nightmarish sounds ever, a strangely distorted male voice screaming in agony... it makes you wonder what the hell kind of transformation is taking place in the kennel, especially since none of the humans are inside of it.
When the men shine their light on the dog-Thing, it lets out an unnerving sound that sounds like a big cat's roar run through an electronic filter. And in the wide shot of the creature, it makes a sound like the electronically processed squeals of a pig.
During the rest of the scene, you continue hearing these weird hybrid sounds of humans wailing/screaming, dogs barking/yelping, and weird growling and hissing sounds. One could simply LISTEN to this scene and get completely unsettled.
After the blood test we notice something that might hit you subconsciously. The blood that was tested to be the creature, after screaming and being dropped to the ground, quickly scurries away consciously, and for the rest of the movie we never see of it again...
The jump scare when Fuch's light goes out. He takes a flare and walks to his door and trips something and all of a sudden we see a shadow shoot by with one of the most horrific sounds ever put on screen. This jump scare mixed psychological horror and paranoia as we don't know who it is and the sound that it makes is so alien and inhuman that it will ALWAYS crawl under your skin.
The same sound is heard when Blair-thing shows up to kill Garry by MORPHING HIS HAND INTO HIS MOUTH, the scene afterwards we're shown his body being dragged by the hand melded mouth.
The Bennings scene.Absolutely everything about this scene is horrific in every sense. The first slow pan from a bloodied chair, to the way Windows slowly turns his head to the source of the noise of Bennings being consumed by the Thing just ends with him softly whispering "shit".
The way that Bennings-Thing looks up when they catch up to it, with seemingly huge eyes. And then it opens its mouth to give off an unearthly wail. Followed by the realisation by the team: Where's Blair?
The frozen Norwegian corpse who slit his wrists and throat.