Revealing mistake: When Tommy Ross gets killed and Carrie looks at his supposedly lifeless body if you look closely you will notice he blinks revealing that he is actually alive.
Continuity mistake: When Tommy collapses on the stage he is facing Carrie, but when Carrie tries to cradle Tommy, he is facing the backdrop.
Continuity mistake: The stain from Carrie's bloody hand on the PE teacher's skirt switches from a smudge in the shower room scene to a full hand-print stain in the principal's office. The stain is also higher on the skirt from where Carrie originally grabbed it.
Continuity mistake: At the beginning of the movie Margaret White gives birth to Carrie. She gets a pair of scissors out of a drawer and tries to stab Carrie in the face. When Carrie starts to cry Margaret picks her up and holds her near her face and the umbilical cord has disappeared. It was there before she picked Carrie up, and she never cut it.
Revealing mistake: During the prom sequence, when the moon-shaped light fixture falls onto the stage supposedly "setting the stage on fire", you can see that it is a fuel line that is starting/controlling the fire.
Other mistake: After Carrie levitates herself and goes outside, there's a wet spot on the concrete that's the size of both her feet, showing her landing spot from previous takes.
Continuity mistake: Chris' mobile phone video of Carrie in the locker room is inconsistent with the event as originally shown when it is projected at the prom to humiliate Carrie. Carrie's cries for help don't occur in the same places that they originally did, and some of them are from before Chris started recording.
Other mistake: The alternate director's cut ending available for viewing within the movie via seamless branching on the Blu Ray is very lazily cut into the film. The music from the previous scene cuts out abruptly when the scene begins, Sue's stunt double's face appears in a close-up shot, and the music from the ending credits abruptly cuts in partway through the song (rather than starting the song from the beginning) once the alternate ending is finished playing. The very end of Carrie's scream from the theatrical ending can also very briefly be heard at the same time the music begins.
Other mistake: The vice principal's mispronunciation of Carrie's name (immediately corrected by Miss Desjardin) is given as "Cassie" in the DVD subtitles, but as "Casey" in the audio. (00:11:07)
Continuity mistake: Carrie still has her shoes until she lands outside where she's suddenly barefoot, then she seems to have them back walking home.
Factual error: In a flashback scene, Carrie's mother is giving birth in bed; there is blood, but no placenta or umbilical cord, which we can see when the mother picks up her baby and places her on her chest.
Chosen answer: It is an implication that Carrie White is not really dead.
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