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.
El Viaje Misterioso de Nuestro Homer (a.k.a. The Mysterious Voyage of Our Homer) - S8-E9
Trivia: When Homer starts tripping on the chili pepper, he sees a distorted vision of Ms. Crabapple and she makes "wah-wah-wah" noises when she talks. These are the same noises teachers are always making in Charlie Brown cartoons.
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.
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.
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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