Trivia: Near the beginning of the episode, Lisa looks at a book and says that Santa's Little Helper was fixed. The book is an actual book that tells about Simpsons episodes, entitled "The Simpsons: A Complete Guide to Our Favorite Family."
The Ziff Who Came to Dinner - S15-E14
Trivia: The couch gag in this episode is bizarrely familiar to a science video shown in school where it shows the universe gradually panning out from two people lying in a field and then rapidly zooming in to show the cells inside the human body.
The Ziff Who Came to Dinner - S15-E14
Trivia: I don't remember all the films presented at the cinema, but there was Eating Nemo, The Fashion of the Christ and A Matrix Christmas. At the opening credits of Cosmic Wars, it's written FOX, a division of Orange Julius.
Trivia: In the warden's office, there is a sign that says "His judgement cometh, and that right soon." This sign also hangs in the office of Warden Norton in the movie "The Shawshank Redemption."
Answer: I'm not sure if this is the one you're thinking of, but an episode of "Ray Bradbury Theatre," called "A Sound of Thunder," dealt with a similar matter: a group of hunters travel back in time to hunt dinosaurs, only to find things have changed when they get back because someone stepped on a butterfly.
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