Trivia: The comic book seller bans Bart and Milhouse for life. When he places their picture on the wall, there are other persons banned. The other persons are: Sideshow Bob, Nelson, and Matt Groening, the creator of the Simpsons.
Trivia: The joke about Martin having an alternate version of 'Return of the Jedi' where Chewbacca is Luke's mother is based on one of Mark Hamill's anecdotes. During the filming of ROTJ he was informed Lucas had something important to tell him in private, which he'd previously done to drop the twist that Vader was Luke's father. This caused Hamill to quip "Oh no, is Chewbacca going to turn out to be my mother?" He was relieved when the actual revelation was that Leia was Luke's sister.
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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