Carrie (1976) - Did You Know?
Ever the stickler for authenticity, Sissy Spacek insisted that she - not a double - be the one whose hand shoots up out of Carrie's grave during Sue Snell's nightmare sequence.
The pig's blood dumped on Sissy Spacek was karo syrup and food coloring, although she was willing to have real blood dumped on her.
While filming the bloody prom sequence, Sissy Spacek's trailer was parked behind the set. After being covered in fake blood, for continuity purposes, Spacek refused to wash the effect off. She elected instead to sleep in her bloody clothes for three days of filming.
In the last scene of the film, Amy Irving's outburst so terrified her mother Priscilla Pointer, that she screamed out "Amy" instead of "Sue." She had never seen her daughter that hysterical and called out her real name in concern. However, the loud ending music covered the mistake.
Brian De Palma had to dump a scene from the novel where Carrie blows up petrol stations with her mind, setting the town on fire. The effects work would have been too expensive.
Brian de Palma' told Sissy Spacek that it was completely unnecessary for her hand to shoot out from Carrie's grave but Spacek persisted. Consequently she found herself put in a coffin and stuck underground. De Palma had her husband, production designer Jack Fisk, put her in the box as he didn't want the responsibility.
In the second-to-last scene (where Amy Irving lays flowers on Carrie's grave) to make it more "eerie", the shot was filmed backwards - then run in reverse in slo-mo - to give it a surreal effect. This is evidenced by a background automobile traversing the perpendicular intersection backwards, which the viewer can clearly observe as driving in reverse.
The script called for a model of the White home to be crushed by a hail of boulders at the end, to tie in with a scene which was cut from the beginning of the movie showing pebbles showering down on the house after Carrie has a fight with her mother. The filmmakers spent an evening trying unsuccessfully to pull off the effect, and as dawn approached, they abandoned the boulders and decided to burn it down. They liked what they saw so it stayed in the film, although internal scenes remain showing rocks coming through the roof.
For when the fire hose kills P.J. Soles's character, the water pressure actually burst her eardrums. Soles is not actually unconscious when her head rolls to the side from the force of the fire hose, but she is in terrible pain and has lost her ability to maintain equilibrium (which is governed by the ear). Brian De Palma decided to keep the shot in. Soles had no hearing in that ear for about six months afterward, though the eardrum did eventually heal.