Tree House of Horror IV: The Simpson's Halloween Special IV - S5-E5
Demon: So, you like donuts, eh?
Homer: Uh huh.
Demon: Well, have all the donuts in the world. [Laughs maniacally.]
[Homer proceeds to eat all the donuts in the world with little effort.]
Demon: I don't understand it. James Coco went mad in fifteen minutes.
Tree House of Horror IV: The Simpson's Halloween Special IV - S5-E5
[Homer runs naked through the kitchen, where Patty and Selma are eating.]
Patty: [after seeing Homer.] There goes the last lingering thread of my heterosexuality.
Tree House of Horror IV: The Simpson's Halloween Special IV - S5-E5
Homer: Kill my boss?! Do I dare live out the American dream?
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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