The Old Man and the Lisa - S8-E21
Trivia: Guest star Bret Hart is missing the four hearts that are usually on his right thigh.
Trivia: Lisa says she is laughing at a joke from "Herman's Head." Yeardley Smith, the voice of Lisa, was one of the stars of "Herman's Head" (1991).
Homer's Barbershop Quartet - S5-E1
Trivia: Some Beatles references in this Beatle mirroring episode: more obviously the rooftop concert, Abbey Road-esque second album cover, the Japanese Artist (Yoko) and the song Number 8 sounding like a dumbed down version of Revolution Nine. Probably less obviously is the closing line, 'I Hope We passed the audition' is the end of the rooftop concert and "Let It Be" album. On the back of the Be Sharps album is the four members in similar poses (hand positions and with Homer with his back to camera) to the inner sleeve of "Sgt. Pepper". The greeting at the JFK airport, their managers 'Boys, you've just recorded your first number one', mimicking George Martin on hearing "Please, Please Me", the cries of "Wiggum forever, Barney Never" echo the "Pete Best Forever, Ringo Never". The list goes on.and on.and on.
Trivia: In New Zealand when the show was being shown on the TV2 network, the Itchy & Scratchy cartoons over a period of time were continually edited to try and remove as much violent content from them as possible. However around 2000-2001 the network edited out every single Itchy & Scratchy cartoon making the cartoon almost non-existent in the show despite some of the cartoon's content not being as objectionable as the rest.
Trivia: Once Bart witnesses Flanders' "murder" the show becomes a takeoff of Alfred Hitchcock's "Rear Window" (1954). Bart is spying on the neighbors while his leg is in a cast, just as Jimmy Stewart does in the film. He even sees an older man with his leg in a cast looking back at him. The man calls for "Grace" to come see the sinister kid. Grace Kelly played Lisa, Stewart's girlfriend in the film. Stewart watches as Lisa goes snooping through the neighbor's house just as Bart watches Lisa Simpson. And when the neighbors come home, they both call for "Lisa" to get out of there.
Trivia: If you watch older episodes versus newer ones, Homer's voice changes noticeably. Dan Castellaneta claims that doing the original voice became too taxing on his vocal cords, so he gradually morphed into talking in the voice we now recognize.
Tree House of Horror II: A Simpsons Halloween - S3-E7
Trivia: During the opening, the tombstones the camera passes by read 'Bambi's Mom,' 'Jim Morrison,' 'Cajun Cooking,' 'Walt Disney,' and one that says 'Lose Weight Now, Ask Me How.' (00:00:45)
Tree House of Horror X - S11-E4
Trivia: When the Collector places Lucy Lawless inside the plastic bag, you can see Dr Who and Matt Groening (The Simpsons' creator) in plastic bags among others. (Matt's the man with the beard and glasses.).
Lisa's Rival - S6-E2
Trivia: When Homer's sugar melts, he says 'Melting. Melting, oh what a world.' This is exactly what the Wicked Witch of the West says when she melts in The Wizard of Oz (1939).
Missionary: Impossible - S11-E15
Trivia: At the end of the episode when Betty White is asking for donations, you can see characters from many other Fox shows manning the phone lines: Bender the robot from Futurama, Hank Hill from King of the Hill, Thurgood Stubbs from The PJ's, Mulder from X-Files, and Luke Perry from Beverly Hills 90210. The owner of Fox, Rupert Murdoch,is also answering phones. The logo from Family Guy is also on the TV Betty White turns off.
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.
Trivia: Marge is accused of shoplifting and hires Lionel Hutz, played by Phil Hartman, as her attorney. In the middle of the trial, Lionel gets an urge for whisky, so he calls his AA sponsor, David Crosby of Crosby, Stills, Nash and Young. When Crosby answers the phone he is looking at the CSNY emblem on an album, which Phil Hartman designed himself in the late '70s.
Trivia: Creator Matt Groening holds the world record for the most DVD commentaries by one person. In total he has done over 100 commentaries over the first five seasons on DVD. The only episodes from seasons 1-5 he has not commented on are "Call of the Simpsons", "The Telltale Head", "The Crepes of Wrath" (all season one), "Homer and Apu" and "Secrets of a Successful Marriage" (both season five).
Trivia: The 'nerd' with the thick glasses is based on the show's creator, Matt Groening.
The Computer Wore Menace Shoes - S12-E6
Trivia: Although Homer claims not to have a computer, he used one in the episode "King-Size Homer" when he was assigned to work at home due to his hyper-obesity. However, this was installed by (and likely remained the property of) Mr. Burns. In "El Viaje Misterioso de Nuestro Jomer", the "Space Coyote" instructed him to get more possessions, and reminded him that he did not even own a computer. On the other hand, during the meteor shower in "'Scuse Me While I Miss the Sky", Marge makes a reference to a screensaver, implying that they do own a computer ("This is even better than our screensaver. And I love our screensaver.").
Trivia: "John Jay Smith," credited as a guest star at the end of the episode, is in fact Michael Jackson, who starred as the man who thought he was Michael Jackson under a pseudonym. Michael is a massive fan of the show and also co-wrote the Simpsons' early hit, "Do the Bartman."
Trivia: The line "If you should die before you wake," uttered by the clown bed is a copy of a scene from the film 'A Nightmare on Elm Street'.
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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