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Nightmare Fuel: Poltergeist
If you're a kid, the scenes with the evil clown puppet and the carnivorous tree are straight out of Hell. If you're a parent, the mother's struggles to reach her endangered children, as corpses pop up out of the pool and floors all around her, are even worse. And the bit where the researcher claws at his own disintegrating face in the mirror gets to everyone.
What about when the giant flaming skull pops out of the portal in the closet?
Far more what it represented. Steven was told not to pull on the rope by Tangina - he did it anyway, and what came out attached to the rope wasn't his wife — it was the beast.
And the simple fact that it all unfolds in somebody's home, not out in the woods or whatever, is pretty creepy. How many people who watch this for the first time can avoid looking suspiciously at their closet doors for several nights?
The chairs stacking themselves offscreen. So simple. So threatening.
The movie has an uncanny tendency to have long scenes of relative calm and normalcy (even after the poltergeists have made their presence known) only for the HSQ to suddenly turn up out of nowhere as things start bursting out the closet, toys start moving around on their own, and bright lights start shining. It has a thoroughly unnerving effect.
A bit of Enforced Method Acting, said to have been Spielberg's idea. Some of the corpses in the final scene were real.
Tangina's expository monologue, detailing what was going on and what they were up against, never, ever fails to chill me to the bone.
The sequel introduces Reverend Kane and boy does he ever leave a permanent mark on the series.
The confrontation through the screen door was probably the most frightening scene in the movie.
What's even more scary is that there was some Parapsychology Truth in Television in that scene. Most poltergeists can't enter a home without being let in by the owners. The fact that an easily breakable screen door is keeping a monster like Kane from haunting them is terrifying.