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Nightmare Fuel: Monsters, Inc.
This line from Waternoose: " I'll kidnap a thousand children before I let this company die, and I'll silence anyone who gets in my way!"
Overlapping with Paranoia Fuel, Randall uses his invisibility to absolutely chilling effect against Sulley. Since he's invisible to the audience too, we're held up in suspense once he disappears and starts scampering all over the place.
An especially effective moment is when Sulley and Boo are hiding on the scare floor... and Randall materializes right beside them.
The Scream Extractor. Dear Lord, the Scream Extractor. It's demonstrated that it extracts the breath as well as the screaming.
When the monsters harvest screams from little kids, a monitor displays how much screams they have collected with Celia announcing such events in a deadpan fasion. Strangely similar to the telescreen. Creepy.
This movie takes "Nightmare Fuel" to its most literal point. The screams of terrified children are what the monsters use for power.
On the DVD, there was an Easter egg that showed the giraffe used to measure height on Boo's wall moving, then peeking around her door to look straight at the camera.
It was also in the movie in two scenes—supposedly.
The scene of Sully being strangled by an invisible Randall. It's mixed in with the comedy of Mike being completely oblivious, but hearing his breath slowly leak out as well as the dramatic music is very disturbing.
To top the whole page is the scene where Sully is trying to explain to Waternoose about Randall's secret scaring and planning on using the Scream Extractor on little Boo. Only to be interrupted annoyingly again and again by him about 'demonstrating' his roar to the trainees present. Not only was that the most traumatic part of the whole film since Boo was traumatized some by the very ghastly sight of Sully in his mostly serious form but it also has a bit of tear jerking for Sully too since he didn't know that Boo was present in the Simulation Room with him. He didn't mean to scare Boo and harm her in anyway.