Skinner's Sense of Snow - S12-E8
Trivia: The episode is based on an event that happened to writer Tim Long in elementary school. He was trapped in Exeter Public School, in Exeter, Ontario, Canada.
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."
Trivia: Troy McClure's strange house that looks like a UFO on a pole is based on an actual house in the Hollywood Hills that looks just like that. It can be seen in Brian De Palma's film, "Body Double" (1984).
Trivia: The show was to have spawned a live-action spinoff, "Krusty the Clown", starring Dan Castellanata. Matt Groening abandoned the project in order to concentrate on "Futurama".
Brother From Another Series - S8-E16
Trivia: Sideshow Bob is voiced by Kelsey Grammer, who plays the title role in the hit comedy series Frasier. The voice of Bob's brother Cecil (hence the title of the episode) is provided by David Hyde Pierce, who is Frasier's brother Niles in the show. There are many in-jokes included in the episode - the white type caption on the black background bridges scenes in Frasier, and "Maris" is Niles' wife, never seen but always talked of, for example.
The Twisted World of Marge Simpson - S8-E11
Trivia: Cletus and Brandine's children are called Tiffany, Heather, Cody, Dylan, Dermott, Jordan, Taylor, Brittany, Wesley, Rumer, Scout, Cassidy, Zoe, Chloe, Max, Hunter, Kendal, Kaitlin, Noah, Sasha, Morgan, Kira, Ian, Lauren, Q-bert, and Phil. Rumer and Scout are two daughters of Bruce Willis and Demi Moore, who were married when this episode was made.
Trivia: Bart changes the lyrics to Iron Butterfly's "In-A-Gadda-Da-Vida" to "In the Garden of Eden." This was in fact the original title of the song, but because Ron Bushy had difficulty listening through a headset, he misinterpreted the title. It was not due to Doug Ingle being drunk while singing, as the popular rumor has it.
Trivia: Comedian George Carlin appears in the episode as a former hippie. In "Homie the Clown", Krusty is told he's being sued by Carlin for stealing Carlin's "seven dirty words" material.
The Mook, the Chef, the Wife, and Her Homer - S18-E1
Trivia: When Martin Prince talks to Otto complaining that Kearney has stolen his instrument, the two pens in his shirt pocket look like "SS"-Runes. (00:01:35)
The Lastest Gun in the West - S13-E12
Trivia: The weapons that Snake and his gang use in the bank robbery are the M41A pulse rifles from Aliens.
Trivia: The cars in the Hollywood Car museum are the Munster Mobile, The Monkee Mobile, The Bat Mobile, The Flinstones' car, Herbie the Love Bug, The Dukes of Hazzard car, and The Road Warrior from Mad Max.
Trivia: When the commercial is on about the lottery, the guy on the right is Lenny, just with a different color of hair. (00:01:35)
Tree House of Horror XII - S13-E1
Trivia: When Homer is threatened by the house, lots of devices come out of the walls and move towards him. One of them is the mechanical hammer that Homer himself invented in 'The Wizard of Evergreen Terrace', when Homer visits the Edison Museum.
Kill the Alligator and Run - S11-E19
Trivia: On spring break there's a veejay named "Sepulveda" who is replaced when she gets too old by another one named "Cienega." Sepulveda and La Cienega are both the names of major streets in Los Angeles.
Trivia: The Simpson family appeared in the Tracey Ullman Show as crudely drawn cartoons. Matt Groening had submitted basic sketches to the animators and assumed they would clean the figures up during production, but instead the animators just re-traced Groening's drawings.
Trivia: Homer becomes the owner of the Denver Broncos at the end of the episode, much to his chagrin as he preferred to own the Dallas Cowboys and the Broncos are bumbling. In real life, the Broncos won two consecutive Super Bowls not long after this episode aired, while the Cowboys have been mediocre at best since.
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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