Cassandra Truth examples on The Simpsons.
- In "Marge Gets a Job", Bart is attacked by a wolf at school. Naturally, because he's "cried wolf" so many times before, no one believes him, even when he had signs that he had been mauled.
- "Simple Simpson" has Homer taking on a superhero identity: Pie Man, who throws pies into the faces of wrongdoers. Towards the episode's end, rather than submit to an attempt to blackmail him into pieing the Dalai Lama, Homer outs himself as Pie Man. Nobody believes him as they all think Homer would never be smart enough to even come up with a secret identity in the first place.
- Homer has been barred from Moe's Tavern, and has borrowed an airline uniform in order to gain access to the pilot's bar:Man: We need a pilot, pronto!... You!
Homer: But I —
Man: Hey, you're not just impersonating a pilot so you can drink here, are you?
Homer: (ashamed) Yeah... that's exactly why I'm here.
Man: (laughs) You fly-boys, you crack me up!
Homer: (being pushed into the cockpit) But I keep telling you I'm not a pilot!
Man: (brusquely) And I keep telling you you fly-boys crack me up! - In "Hungry, Hungry Homer" Homer goes on a hunger strike because no one will believe him when he finds out that Duff Beer is planning to move the local baseball team to Albuquerque. Homer even provides a fitting quote for this trope:
"I don't mind being called a liar when I'm lying, or about to lie, or just finished lying. But not when I'm telling the truth!"
- "Bart Simpson's Dracula" from "Treehouse of Horror IV".Lisa: Mom! Dad! Mr. Burns is a vampire, and he has Bart!
Mr. Burns: Why, Bart is right here.
Bart: (monotone, with noticeable bite marks) Hello, Mother. Hello, Father. I missed you during my uneventful absence.
Homer: Oh, Lisa, you and your stories. "Bart is a vampire." "Beer kills brain cells." Now let's go back to that... building... thingy, where our beds and TV... is. - In "Treehouse of Horror VII", Homer is abducted by Kang and Kodos, who glean the identities of presidential candidates Bill Clinton and Senator Bob Dole from him and abduct them and take their place in order to Take Over the World during the 1996 Presidential campaign. Homer tells the aliens that he is going to tell everyone and put a stop to their evil plan. They spray him with rum and then send him back to Earth, saying that no one will believe him. When he gets home and tells the family, no one believes him because they think he got drunk at Moe's. (It certainly doesn't help that he tries to claim that before he was abducted by aliens, he caught a fish this big.)
- In "Lisa the Iconoclast", Lisa uncovers proof that Jebediah Springfield's heroism was all fraudulent, but even Marge, who usually supports her crusades and protests, refuses to believe her. The only person in the whole town who believes her, oddly enough, is Homer.
- Chief Wiggum treats everyone like they're telling Cassandra Truths. Even to the point where an obvious arsonist walks into the station to give himself up. Wiggum dismisses him as a loon not worth listening to.
- When Mr. Burns' grandfather fires an employee of his atom-smashing mill for stealing six atoms, the employee gives a warning of things to come:Young Man: You can't treat the working man this way! One of these days we'll form a union and get the fair and equitable treatment we deserve! And then we'll go too far and become corrupt and shiftless; and the Japanese will eat us alive!
Burns' Grandfather: The Japanese?! Those sandal-wearing goldfish-tenders? Bosh! Flimshaw!
Burns: (Present-day) Oh, if only we'd listened to that young man, instead of walling him up in the abandoned coke oven. - "Curse of the Flying Hellfish" derives a lot of its humor from the fact that Grandpa Simpson is actually telling the truth about something from his past, when normally, his stories are tedious, ludicrous, and fueled by senility. In the episode itself, he claims to have "invented the terlet" and chased the Kaiser to reclaim the word "twenty" when it was changed to "dickety", and in prior ones, he claimed to have gone undercover as a cabaret dancer to kill Hitler, so it's rather sensible that nobody believes him when he claims he was part of a valuable Tontine after a career as one of the most decorated soldiers of World War II.
- In "My Sister, My Sitter", Lisa calls 911 to inform them that Bart is severely injured and needs an ambulance. They dismiss it as another prank call (even though it was Bart who made the calls beforehand, but it could just be sheer stupidity on their behalf) and hang up.911 operator: Simpson? Look, we've already been out there tonight for a sister-ectomy, a case of severe butt rot and a leprechaun bite. How dumb do you think we are?
