Trivia: Dan Castellaneta and Hank Azaria both voice about ten regular characters, with Azaria contributing another ten recurring, and Harry Shearer voices twelve regulars.
Trivia: In a recent episode (I saw it when it premiered on 5/17/09) the Odgenvillians move into Springfeild, then are forced out. When Lenny and Carl go on the chair attached to balloons, you can see the house for Pixar's latest film, Up, in the background.
Trivia: Ned Flanders inspired the term "Flanderization", used to describe TV characters who started off with a few personality traits, but are now dominated by just one. In earlier seasons, Ned was a polite, respectful man who attended church, but was not especially pushy about religion. He and his family became more strictly Christian, portraying a "Bible-beater" stereotype.
Trivia: In the opening sequence post Feb 2009, Marge can be seen placing items on the checkout. These include the detergent Mr Sparkle from Season 8 Episode 22, In Marge We Trust, and some Tomacco juice from Season 11 Episode 5, E-I-E-I - (annoyed Grunt). (00:00:25)
Trivia: Sideshow Bob's passion for singing is a dimension to the character that was uniquely Kelsey Grammer's, stemming from his own personal history of singing standards on the set of Cheers.
Trivia: Despite playing father and son, the actors who voice them are actually almost exactly the same age. Nancy Cartwright (who voices Bart) is actually 4 days older than Dan Castellaneta (who voices Homer).
Trivia: The property next to the Simpson house is very versatile. It has been Flanders house (both sides), a cemetery, the parking lot to the nuclear plant and a vacant lot.
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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