Revealing mistake: Trish jumps out the window and lands face up on the ground. You can plainly see it's Kimberly Beck's stunt double. She looks nothing like her. (01:21:35)

Friday the 13th: The Final Chapter (1984)
Plot summary
Directed by: Joseph Zito
Starring: Crispin Glover, Corey Feldman, Peter Barton, Erich Anderson, Judie Aronson, Kimberly Beck
Genres: Horror
Thought to be killed by the sole survivor of the last Crystal Lake Massacre, Jason kills all the way back to the lake to once again murder its inhabitants. This time, has Jason met his final match with a little boy named Tommy.
More mistakes in Friday the 13th: The Final Chapter More quotes from Friday the 13th: The Final ChapterMore trivia for Friday the 13th: The Final Chapter
Jimmy: Ted. I think... I think when we get to town I should call Betty.
Ted: Jimbo, calling Betty is definitely a dead fuck thing to do. Look, first rule of love: never get rejected by the same girl twice. I mean, that's useless. If you want to make a fool out of yourself, always do it with someone new.
Jimmy: I don't know anyone new.
Ted: Well, sex is a great way to meet them.
More questions & answers from Friday the 13th: The Final Chapter





Answer: Jason killed her. There was a scene shot but never shown where Trish discovers her mom's body.
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