You Do NOT Want to Know



""Trust me on this: you don't wanna know. Audrey? Don't tell him. You shouldn't've told me, but you did, and now I'm telling you, you don't wanna know!""

- Joshua Sweet on Mole's past in Atlantis: The Lost Empire

Some secret about Character A is mentioned, either by the character himself, or by somebody else. When queried, someone replies "You don't want to know. Just trust me on this." Or words to that effect. Whether we actually find out what it is varies - if we don't, it can turn into a Noodle Incident, and might be set up for one or more un-reveals. The characters who do know will usually try to avoid talking about it. More often than not, this phrase can just end up as Schmuck Bait.

In other cases, we do find out. If played for comedy, the secret will turn out to be relatively innocuous - or at least, not nearly as far-out as what the other characters - and probably the audience - have imagined it might be. If played for drama (as in horror movies) it'll turn out that the secret is, indeed, quite bad, and that the others would, in fact, have been better off not knowing.

A Genre Savvy person can start to ask, and then conclude that no, they're better off not knowing. If curiosity gets the best of them, it will be followed with "I'm afraid to ask, but..."

And sometimes, it's just Too Much Information.

Other stock phrases include "I don't want to know, but at the same time, I really want to know...", "That means you do not want to know, trust me.", and "Don't Ask."

If said by a mentor, it is likely to be an Awful Truth. If they experience enough such events, leads to a character who has Seen It All.

Not to be confused with These Are Things Man Was Not Meant to Know... even if, in some cases there may be some overlap.

See also Take Our Word for It, I Have My Ways.

Anime and Manga

 * In One Piece. the closest the Straw Hats came to learning what Gol D. Roger's eponymous treasure was or where it is came during the Sabaody Archipelago Arc when Usopp tried to ask Silvers Rayleigh about it. Luffy angrily interrupted, indicating that he did not under any circumstances want to simply be told about it, stating that such knowledge would defeat their purpose. It seems likely that someone will eventually find out what One Piece is, but it won't be that easy.

Fan Works
"Mal: Kaylee, find something for the doc to do. He don't need to be fussin' the whole time we're gone. Kaylee: He and I can– Mal: I don't want to know. Some things I really, really don't need to hear, little Kaylee. Kaylee: I was gonna say 'we can finish up some repairs in the kitchen'. Why, what did you think I was gonna say?"
 * The Man With No Name has this:

Film
"Jack Burton: "Oh my God, what is that!? Don't tell me!" Egg Shen: "Lo-Pan's spy. What it sees, Lo-Pan knows!" Jack Burton: "I said, 'don't tell me!'""
 * Used for an extended gag in Atlantis: The Lost Empire, when Milo asks Audrey about the backstory of Gaetan 'Mole' Moliere, after having heard the backgrounds of the rest of the cast. She's just opened her mouth when Dr. Sweet delivers the page quote. Seeing as Moliere is a short, creepy French dude obsessed with soil and rock, not to mention an intense aversion to bathtime, he may be right.
 * In the sequel, Milo say that he thinks Moliere was raised by naked mole rats. Of course, given that it went Direct to Video...
 * In an issue of Disney Adventures, it was stated that he spent most of his childhood exploring in the sewers of Paris.
 * The third Jurassic Park movie, when Alan Grant discovers the missing kid has collected a jar of Tyrannosaur urine, the smell of which scares most dinosaurs away. How? You don't wanna know.
 * Played with in Big Trouble in Little China, when the heroes meet Lo-Pan's beholder-like eye-covered spy creature:

"Stanley: Hey, George, is something wrong? George: Stanley, you don't want to know. Stanley: (Scratches head in confusion) Then why'd I ask?"
 * Used as a joke in UHF:

"Young Robert: Well... it was something he said. William Shatner: What'd he say? Young Robert: You really don't want to know. William Shatner: I really do want to know! Young Robert: He said that Han Solo was cooler than Captain Kirk. [ Beat] William Shatner: Kick the little fucker's ass."
 * An exchange in Free Enterprise has an imaginary William Shatner talking with a young version of Robert, one of the main characters, during a fight he got into while wearing a TOS gold uniform. When prompted Young Robert reveals it was he that started the fight.

"Hal: "I gotta see this." Mauricio: "Naw, naw, you don't wanna see this." Hal:: "No, I don't wanna, I gotta.""
 * In Shallow Hal, Mauricio tells Hal he was born with a tail.

"Flass: The bears, they go straight to the dealers. Falcone: And the rabbits go to the man in the narrows. Flass:: What's the difference? Falcone: Ignorance is bliss, my friend. Don't burden yourself with the secrets of scary people."
 * This is a frequent theme in Batman Begins.


 * The Lion King has Simba, when questioned by Timon as to why he is depressed, stating "I'd rather not talk about it." Of course, it's technically a subversion as the audience had seen beforehand why he was depressed, as he had been led to believe that he was responsible for his father, Mufasa's death.

Literature
""I could say twelve words, and when I was done, the least you'd do is turn away and leave me alone forever." He could tell that she was speaking the truth, and the fact that she had the power to do this, to send him away, dismayed him. "Then don't say them.""
 * The novelisation of |V: The Final Battle doesn't have the scene where the nasty young human collaborator Daniel Bernstein gets dragged off to "serve us better" after being framed by La Résistance, but it does have Eleanor Dupres asking what happened to him and being told by a Visitor: "Believe me, you wouldn't want to know!"
 * In the Wraith Squadron books of the X Wing Series, Imperial agent Gara Petothel caused the deaths of every member of Myn Donos's squadron, which sent him into a Heroic BSOD. Later Gara Petothel joined his new squadron with plans to destroy this one as well, but she began to enjoy her life in the squadron as "Lara Nostil" and decided to become a member for real. She and Donos started falling in love with each other, but she knew it could only end badly as she was only going to be able to hide the secret for so long.

"Myn Donos: "I want to make you smile with something other than a wisecrack. I want to know who you really are." Her laugh, sudden and hard, startled him. "Oh, no, you don't.""
 * Later:

"Wedge: "Any of you understand that? Her mood swing?" Tycho: "I think I'd shoot myself before getting involved in this conversation." Hobbie: "Not one of my languages, Wedge." Wes: "I understood her, boss. But you don't want to know. Trust me on this." (Wedge insists, and Wes ends up giving a very accurate, very logical explanation to the girl's behavior. Then…) Wedge: "Wes, you were right. I did not want to know.""
 * In Starfighters of Adumar, a later entry in the X Wing Series, Wedge's young guide falls for him and starts acting strangely.

"Anghammarad: "Neither Deluge Nor Ice Storm Nor The Black Silence Of The Netherhells Shall Stay These Messengers About Their Sacred Business. Do Not Ask Us About Sabre-Tooth Tigers, Tar Pits, Big Green Things With Teeth Or The Goddess Czol." [...] Moist: "The goddess Czol?" Anghammarad: "Do Not Ask.""
 * The Outcast of Redwall features a hare nicknamed Jodd. His full name results in this trope, and in the end we only hear part of it.
 * The Golden Globe by John Varley averts Forbidden Fruit in this regard: to show that you don't want to know how Charonians have sex, you're given a description of their coming-of-age ceremony. For context, Charonians regenerate quickly and worship pain, and the ceremony itself is either Narm or Nausea Fuel.
 * Used in Thud! when Vimes asks about the worst of dwarven signs, the Summoning Dark, and is informs he does not want to know. When he asks again, he's told that no, he really doesn't. He starts to ask again before deciding that in fact that's correct, it's mystical stuff that he doesn't believe in, and drops it.
 * In Going Postal the ancient messenger golem Anghammarad recounts his motto:


 * Similarly, the modern post office declares that neither sleet nor snow nor gloom of night shall stay these messengers about their business, with it's own "don't arsk us about" list. Mrs. Cake appears twice.
 * The Lemony Narrator does this to the reader in Thief of Time, when Famine talks about his love of salad cream sandwiches. A footnote advises readers from societies where the traditional condiment for salad is mayonnaise not to even ask.
 * Subverted and inverted early on in The Hitchhiker's Guide to the Galaxy, when Arthur takes the precaution of asking Ford, "if I were to ask you where the hell we were, would I regret it?" Ford cuts to the chase and tells him where they are. Arthur was probably happier when he didn't know.
 * Used in a decidedly non-comedic fashion in Memory, Sorrow, and Thorn, when Shell Shocked Senior Camaris refuses to tell the protagonists about his mysterious past that led to a Heroic BSOD, on the grounds that it's too shameful. He does confess it twice, once to a priest and once to Prince Josua, and both emerge from the experience wishing they hadn't been told. At the end, it's revealed that he's, and lived his life afterwards in misery over his weakness and the subsequent Death by Childbirth of the woman in question.
 * During a Doctor Who short story, a skeleton grabs the Tenth Doctor by the ankle as it claws its way out of the earth. The Doctor, not taking his eyes off Rose, asks if he should look. She shakes her head.
 * In the Gaunts Ghosts novel His Last Command, Vortenhus is told that he does not want to know what a glyf - a Chaos tripwire-like thing, the sight of which can drive a man insane - is.
 * In The Dresden Files novel Death Masks, Dresden finds himself having a conversation with his friend Michael's teenage daughter Molly, after escaping a situation that left him with handcuffs danging from one wrist. During their talk, Molly produces an entire set of handcuff keyes and finds one that matches the cuffs he's wearing. When Harry asks how she got the keys, she tells him to ask himself if he really wants to know the answer to that question. Harry decides he doesn't.
 * Repeated with the medical pinwheel thing. Apparently they have recreational uses. Molly used to hang out with a weird crowd. Harry decides to not pursue that line of reasoning.
 * Harry tells a bunch of his friends this about the magical world. Eventually, he gives them the option to learn anyway and stand with him. They each take it.

Live Action TV
"Prince George: They pull your breeches down and push a large radish right up your-- Blackadder: --yes! Yes! Yes! All right!...There's no need to hammer it home. Prince George: As a matter of fact, they do often have to-- Blackadder: --No! NO!"
 * In an episode of Blackadder the Third, a French torturer tells the soldier guarding Blackadder and Baldrick that he should leave, since what she is going to do will be so horrifying. He states his belief that he can stomach it, to the hag's increasingly frantic protests, until he asks for a description. She whispers to him, and of course he runs off about to vomit.
 * Also in Blackadder the Third, when Prince George describes what the Naughty Hellfire Club does to people who don't pay their dues:

"Kryten: Logically, sir, there is only one way you could possibly have opened that door. I feel quite nauseous. Where is it? Lister: Where's what? Kryten: Oh, sir!! You've got it in your jacket!!"
 * On the Raquel Welch episode of The Muppet Show, Marvin Suggs reveals to Kermit that he has to replace his living musical instruments, the Muppaphones, when they go flat (like little pancakes). What happens to them then? Well...
 * At one point, he actually was the replacement...turns out that singing the Witch Doctor song when you've been told never to tell anyone is a bad idea.
 * Red Dwarf: Lister opens a secure door and doesn't want Kryten to see how: "Trust me, you don't want to know!". Kryten doesn't look, but of course, being a robot, he correctly guesses the logical answer: Lister used a severed hand from one of the dead crew on the palm print reader.

"Worf (in Sincerity Mode): "Things that would send cold chills down your spine, and wake you in the middle of the night. No, it is better that you do not know. Excuse me." *shambles away*"
 * Subverted in Thanks For The Memory. A drunken Rimmer wants to tell Lister how many times he's made love, to which Lister replies: "I don't wanna know! Trust me, You do not want to tell me!"
 * Rimmer does, of course, and the answer turns out to be embarrassing.
 * In Backwards, before they leave, Lister tells Rimmer that Cat has gone off into the bushes, then he realizes what this entails, and says, "We've got to stop him!" Cat comes back, hair sticking straight up, walking stiffly, horrified expression on his face, and simply says "Don't ask." (For those who don't recall the episode, they were on an alternate Earth where everything happened in reverse...)
 * Used in the first-season Star Trek: The Next Generation episode "The Big Goodbye", where the fate the insectoid Jarada visit upon people who pronounce their ceremonial greeting wrong is so horrible that the crew won't even let Data hint at it.
 * In Star Trek: Deep Space Nine, Worf is asked at a party what Klingons dream about.

"Maxwell Smart: Don't tell me [rest of sentence] Other character: [repeats the rest of the sentence back to him] Smart: I asked you not to tell me that."
 * In "Sacrifice of Angels", O'Brien and Bashir have been quoting "The Charge of the Light Brigade" in the runup to a battle where they're seriously outnumbered. Garak, eventually, asks how it ends. O'Brien tells him he doesn't want to know...which pretty much answers the question.
 * Speaking of insectoids, on an episode of Star Trek: Enterprise, Captain Archer is in VERY tense negotiations with the Xindi; his linguist Lt. Sato performs simultaneous translation—except at one point, where the insectoid goes on a long chittering rant, and Sato simply says "You don't want to know."
 * This is the second time she uses the line. In the pilot episode, a Klingon says something to Captain Archer, who takes it as a thank you. When Sato comments that she doesn't think they have a word for thank you, and Archer asks her what the Klingon did say, she responds with the line verbatim.
 * Used for comic effect in Black Books. Manny says that something bad happens to him at 88 degrees, and Bernard wants to know what, but Manny keeps repeating, "You don't want to know." Bernard at first tells Manny to stop saying that, because he wants to know even more if he's told he doesn't. Then he switches tactics, saying that Manny doesn't know WHY Bernard wants to know. To which Manny replies, "Oh, why's that?" And Bernard has made his point.
 * When a couple came into Night Court who were well known for their outlandish bad luck (the squad car they were arrested in got hit by a bolt of lightning) mention that their granny died, Harry, Dan, and Christine give each other looks before Christine bursts out "Oh what the Hell someone has to ask! How did she die?" They reply that she died peacefully while sleeping... on the railroad tracks.
 * In one episode of The Big Bang Theory, after Leonard's mother and got drunk with Penny and kissed Sheldon, she apologises to Sheldon "about her behaviour" while Leonard is present. Leonard enquires about details, but his mother, Penny and Sheldon all answer that he doesn't want to know.
 * Northern Exposure—In "The Russian Flu," Dr. Fleischman asks Marilyn what's in a foul-smelling (but effective) Native American flu remedy. Her reply: "You don't wanna know."
 * Heroes season three demonstrates how not to do this: a character whose power is treated as a "you don't wanna know" situation turns out to be something pretty basic: your typical sonic scream thing, and not even (that we saw) to Black Bolt-esque mega-destructive levels.
 * Said power was originally intended to be terrakinesis, on par with the Big Bad of volume five, but was cut due to budget restraints at the time.
 * In the Doctor Who episode "Bad Wolf", this is Jack Harkness's response when his captors demand to know how he managed to pull a concealed weapon on them despite being stripped naked.
 * On the U.S. version of The Office, Dwight issues Jim a demerit for tardiness, then explains his made-up, incredibly convoluted warning system for policing the office that, as Jim points out, logically ends with Dwight submitting a disciplinary review to his immediate superior (Jim himself, the Assistant Regional Manager). Jim responds by demanding the review be on his desk by the end of the day, or Dwight will be issued a "full dissadulation." What is that? "You don't want to know."
 * Get Smart used a variation of this in Catch Phrase fashion:

"Marcus Cole: They taught me…terror. How to use it. How to face it. Dr. Franklin: I think I'd like to hear more about that… Marcus Cole: No. You wouldn't."
 * A variant was used in Season 3 of Babylon 5...

"John Sheridan: What the…? Susan Ivanova: Don't…even…ask."
 * A straighter example in Season 4 provides a Crowning Moment of Funny. Susan Ivanova stumbles litter-strewn out of a transport tube, using a cane to stay upright.

"Reese: Doctor has everything she needs to erase Benton for good. Finch: What do you mean, "erase"? Reese: Eight pounds of lye, heated to 300 degrees. Body will dissolve in three hours, give or take. Finch: I will refrain from asking how you know that."
 * In the Monk episode "Mr. Monk and the Miracle", Monk tells Natalie that her getting gravy wouldn't have been necessary as the bums, their guests, make their own gravy. When Natalie asks how they do it, Monk simply responds with "You don't want to know..."
 * Similarly, in "Mr. Monk Is On The Run: Part 1", after Monk arrives back at Natalie's house with a strange overcoat, he said a homeless person gave it to him in exchange for something else in return. When questioned by Natalie about what that thing was that Monk had to do, Monk can only respond with "I'd rather not talk about it..."
 * Person of Interest: in the episode "Cura Te Ipsum"

Newspaper Comics
"Jon: What's the special today? Irma: You don't want to know. Jon: Gimme the special! Garfield: There's a gambler in the house!"
 * In one of the Dilbert compilation books, Scott Adams suggests that when calling in sick to work, the best thing to say is, "You don't want to know the details.".
 * Calvin's mom after he runs inside naked and screaming at a hailstorm; "I'll bet there's an explanation for this, and I'll bet I don't want to hear it."
 * In a Garfield strip, Garfield looks at the box of the cat food he's eating, and sees that it reads: "Ingredients: You're better off not knowing". He keeps on eating, thinking: "What you don't know can't hurt you, right?"
 * In another strip, when Jon and Garfield are at Irma's Diner:

"Liz: Where'd he get the bucket of cherry syrup? Jon: Some things are better left unknown..."
 * In a 2012 Sunday strip, Garfield takes a Snow-Cone container outside when it is snowing. The Snow then fills up in the container, until it reachers snow-cone-like levels, to Garfield's delight. Jon and Liz are watching the entire thing inside, leading to this exchange when Garfield is bringing the cherry syrup bucket:


 * FoxTrot had Roger telling Andy this about how doped up she was from her allergy medication upon being asked after going off it.
 * Phoebe and Her Unicorn has points of resemblance to Calvin and Hobbes, so it's not surprising when Marigold the unicorn explains that she and Phoebe became best friends after Phoebe hit her in the face with a rock, and Phoebe's maybe-Frenemy Dakota replies, "I'm sure there's more to that, and I don't wanna know it."

Theater

 * About 80% of Oedipus the King is this trope.

Video Games
"Malfurion: They [Illidan's naga] had best return with good news. The very sight of them makes my stomach turn. Where did you ever find such loathsome creatures? Illidan: Believe me, brother: You don't want to know."
 * In Warcraft III: The Frozen Throne, Illidan uses this line on Malfurion.

"Raine: *Evil Laugh* Lloyd: What was that about? Genis: You're better off not knowing..."
 * Tales of Symphonia take after Raine disappears into the Iselia shrine:

"C8-42: "I'm afraid my owner became a bit too attached to me. Obsessed even. She...she tried to treat me as her dead husband. It was not healthy for her." Player: "Er... ALL the time?" C8-42: "You don't want to know..." Player: "Um... probably not...""
 * Players of Knights of the Old Republic are treated to this little exchange on Dantooine:

"Mitsuru: Oh, Mr. Ekoda’s punishment...? Well, there are some things in life you don’t want to know about... This is one of them."
 * Persona 3

"Master Chief: "How much time was left?" Cortana: "You do NOT want to know.""
 * Same applies to Mitsuru's "Execution."
 * In Quest for Glory III, if you ask the meat merchant the second time about meat, the system replies, "On second thought, you don't want to know."
 * In Halo 2, in a cutscene early in the game, Master Chief disarms an elite bomb with the help of Cortana.

"Winslow: I'll keep an eye on Miss LeFlay. If she stirs, I'll give her the old scurvy buttons! Guybrush: [disturbed] I don't want to know what that is."
 * Tales of Monkey Island: In Chapter 3:

"Guybrush: If I plead guilty, will I get out of here any quicker? Judge Grindstump: Most definitely-- Guybrush: Great! Then I plead-- Judge Grindstump: [interrupts] After the summary executions by keelhauling, hanging, boiling, and, eh, em... scaphism. [the crowd laughs] Guybrush: [confused] Scaphism? Stan: Trust me, kid, you don't want to know. Guybrush: Okay, then..."
 * And in Chapter 4:


 * In Saints Row the Third, the player character asks Shaundi what a "Feel Boss" is. She simply responds with: "You DON'T wanna know."

Web Animation

 * In Red vs. Blue Church encounters multiple versions of himself due to time travel, including one who is an odd yellow color. When asked how he got like that, he simply replies, "Dude, Don't Ask."
 * In season five, it turns out.
 * Well, It Seemed Like a Good Idea At the Time.
 * If you want to know how to animate the titular character from Homestar Runner, it involves a pair of underpants with ping-pong sensor nodes on it. Matt quotes this word for word after showing the viewer this.

Web Original
"Keith: So... what happened to you? Kickaha: You don't want to know. Keith: WHAT? We're probably the only two people on this planet that can have this discussion, and you're telling me that I don't want to know? Kickaha: Look. You don't understand. You were there. You told me. You don't want to know."
 * In the Yu Yu Hakusho Abridged movie, after Yakumo, Yusuke asks what Kurama sounds like and Kuwabara answers with this trope. Averted anyway since Kurama ends up speaking enough to say: "I HATE all of you."
 * In Part 15 of A Trickster's Tail, after the two of them have escaped the afterlife and Keith has related his adventure to Kickaha.

"Blobert Smith: My character deals with his post traumatic stress by putting porridge up his nose on moonlit nights. Weasly Crusher: Why would he- El Disgusto: Don't! Just don't."
 * In The Binder of Shame, this is used occasionally.

Webcomics
"Spike: How did you get a Sacagawea dollar to penetrate your front grill and lodge itself in your carburetor? Leo: You don't want to know. Spike: Why are you dressed as a ninja? Leo: I don't want to tell you."
 * Toyed with by fan favorite Sasha in Sluggy Freelance: "Part of me wants to say 'I don't want to know', but I do! I really, really do!"
 * Also here:

"Breya: I... I really want to know, but I think I'm afraid to ask. Tagon: That's a good sign that you don't really want to know."
 * Schlock Mercenary, on the subject of [//www.schlockmercenary.com/2004-03-20 a carbosilicate amorph not using the toilet]:

"Elf: I don't want to know. Aardman: Yes you do. You just don't want to admit it."
 * Also inverted - [//www.schlockmercenary.com/2009-04-11 involving Schlock again]:

"Trevor: ...the sergeant can make his merry way to any one of these locations and do his thing. Whatever "his thing" is. Kathryn: "His thing" is one of those "the less you know about it the happier you'll be" things. Trevor: I'm unhappy just knowing those things exist."
 * Admiral Tebbir would feel better [//www.schlockmercenary.com/2006-04-04 trusting Petey on this one] (see the next 3 pages).
 * A belated realization from a retired (and hired by another party) military intelligence analyst (amazingly, they discuss not an assassination, but something ostensibly innocent):

"Breya: There are going to be many interesting things for you to see. Sorlie: Will I want to un-see any of them? Breya: ...many, many things."
 * Captain Haley Sorlie is a [//www.schlockmercenary.com/2015-03-18 fast-learner]:

"Faye: Dora, we have a freaked-out naked chick scrubbing herself furiously in our bathroom. Dora: Meh, it's not the first time. Faye: I... I don't want to know, do I. Dora: Probably not."
 * Used once in Penny Arcade: "Wow, it's like...I want to see it? But at the same time, I don't want to see it."
 * In a subversion, that's just Gabe Comically Missing the Point; Tycho's being kicked out of being a man.
 * Pops up in Questionable Content, here. Speculations on what it could be runs rampant amongst the cast (and the fanbase) before it's finally revealed to be more nerdy than anything else...
 * Also this strip.

"Artax: The more i learn about gods, the less i want to know."
 * Marten [//www.questionablecontent.net/view.php?comic=573 catches himself] asking a question he doesn't really want answered.
 * Freefall uses a variation on this.
 * Not if you want to sleep, at least.
 * Nodwick theology has this effect:

"Roy: Part of me wants to know a story behind that, while the other, smarter part of me knows it's better off in ignorance."
 * Order of the Stick has this:

"A rabbit: So, what do you like to eat? Dusk (a fox): Kid... never ask a question if you won't like the answer."
 * Faux Pas

"Eastwood: Why do you have...? Syrus: Only finish that question if you really wanna know the answer. (East mimes zipping his lips shut.)"
 * In Exterminatus Now, Syrus had just KO'd Wildfire with a chloroform rag after one too many screwups:

"Jake: "If past experience is any indication, we'll be better off not knowing.""
 * The Whiteboard: A common reaction by the regulars when Sandy or Pirta asks about any particular weirdness happening.

"Lia: Don't. I know you want to explain what he means by that, but don't."
 * Used in Yosh! in response to an accidental Double Entendre.

"Scavenger Captainbot: There is now literally no question I could imagine asking you that I am not in mortal terror of finding the answer to."
 * Vexxarr, on subject of the protagonist personally starting a war:

"Black Mage: Don't ask him. He'll tell us."
 * 8-Bit Theater with one of predictable silly ideas from Fighter:

Western Animation
"Farnsworth: This is no ordinary honey. It's produced by vicious space bees. A single sting of their hideous neuro-toxin can cause instant death! Hermes (happily): And that's if you're not allergic! You don't wanna know what happens then. Oh no, no. God no! Farnsworth: Your insides will boil out of your eye sockets like a science fair volcano! Hermes (sobbing): I didn't want to know!"
 * Seen in Futurama, "The Sting".

""I don't think I want to know." "We're all in a cage match fighting to the death." "Yeah, see?""
 * And you really don't want to know whose behind comes out of. Same episode, the same is said of where toothpaste comes from.
 * In Transformers Animated when, her response is "Don't ask!"
 * Funnily enough, Word of God states pretty much the same thing.
 * The smell of Unfortunate Implications is really strong here.
 * In an earlier episode, Prowl, Bumblebee and Sari go on a camping trip, and the latter two bring all manner of gadgets. Prowl, unimpressed, asks Bee where he found room for all of it in his vehicle mode. "I'd...rather not say".
 * In an episode of Justice League, having just captured an assassin who tried to kill Aquaman, several members of the League threaten him with physical violence, which he shrugs off. Batman then takes him aside and whispers something to him, he practically begs to tell everything he knows. When Wonder Woman asks Superman what was said (Supes, of course, possesses acute hearing) he tells her that she doesn't want to know. Made even better by the expression on his face. According to Kevin Conroy, the actor who played Batman, he said "".
 * Also, in the Forced Prize Fight episode "Grudge Match", Hawkgirl's reaction after being snapped out of mind control;

"Wade: I don't know what to tell you Kim. After watching the cafeteria security tape, I can't explain what happened either. Kim: Did you analyze the gravy sample? Wade: Yup. Monique: And? Wade: You don't want to know. (Beat) Not till after graduation. (Beat) From college. Monique: I say we trust him on the gravy."
 * In the Ben 10 episode "Ken 10" Ken rejects adding an alien called 'Toepick' to the Omnitrix, saying "He even grosses me out!". The pop-up edition plays this up by having the pop-up say "You don't want to know".
 * In Invader Zim's Crapsack World, people inexplicably hand out meat on Valentine's Day. When Dib asks how this tradition got started, Ms. Bitters (who never had a problem telling the children disturbing truths before) simply replies that he doesn't want to know.
 * In The Real Ghostbusters, the episode 'Knock, Knock' has Egon look into the room that holds the door to Doomsday. When asks what he sees, he replies 'you don't want to know' in his usual calm, dull tone of voice.
 * Kim Possible, in a scene involving a "gravy ghost" spelling words in the high-school cafeteria gravy;

"Mr. Barkin: And don't let them tell you that they're supposed to have class outside! We put a stop to that after the jellyfish episode. Miss Go: Oh, that's so sweet! You took the class to the beach! Mr. Barkin: No beach. Just jellyfish... [shudders] Don't ask."
 * Another example, when "Miss Go" (Shego temporarily turned good) arrives to teach one of Kim's classes:

"Lisa: But what if he wants to hold hands? Bart: I'm prepared to make that sacrifice. Lisa: What if he wants to kiss? Bart: I'm prepared to make that sacrifice. Lisa: What if he wants to- Bart: You don't want to know how far I'll go."
 * In the Strawberry Shortcake Berryfest Princess Movie, Blueberry Muffin walks in on Strawberry Shortcake doing a bunnyhop and sorting mixed nuts with Plum Pudding at Orange Blossom's general store and comments, "Do I wanna know?" A little while later, after reading a map has been added to Strawberry's tasks, Orange returns, also commenting, "Do I wanna know?" "That's what I said," Blueberry tells her.
 * In My Little Pony: Friendship Is Magic, it turns out that the three story tall celestial bear that attacked Ponyville was an Ursa Minor—a baby. When asked what an Ursa Major is like, Twilight gives this response.
 * Also Rainbow Dash says it after Twilight wonders what Dash meant by "At least I haven't been replaced by turnips"
 * In The Simpsons episode "I Love Lisa," Ralph Wiggum has tickets to Krusty's anniversary show, and he invites Lisa. Bart really wants to go, and he suggests disguising himself as Lisa.


 * A Simpsons TV Episode guide also used this phrase on the subject of how Kang and Kodos could tell each other's genders.
 * Another episode had Bart rubbing his ear industriously and acting sick so that when Marge took his temperature (through his ear) it would come out to 103 F and he could stay home. She says the only way to be sure was to use the rectal thermometer. It still came out to 103. When Lisa asked, Bart says she doesn't want to know.
 * In the He-Man and the Masters of the Universe episode "The Origin of The Sorceress", Teela-na, the future Sorceress, gets this line from a young town who had been watching the villain of the day and a alien race argue over things.
 * In an episode of the ongoing Hercules series, the water of the Spring of Canathus turns Hercules, Icarus, Pegasus, Adonis, and Hades' minion Pain into infants, which results in Cassandra and Hades other minion Panic becoming Badly-Battered Babysitters for the rest of the episode. When the curse is finally undone, Hades shows up, and at first, he asks why everyone is wearing diapers, but then he changes his mind and says he doesn't want to know, and leaves with his two servants. However, Hercules and his friends do want to know what happened, and after Cassandra tells them, they all beg and plead with her not to tell anyone.
 * In an episode of The Grim Adventures of Billy and Mandy, Grim gives Billy a gumball machine that yields a limitless amount of gum, but warns him never to swallow the gum. When asked what will happen if he does, Grim says, "Trust me, you don't wanna know. If I had skin, it would be crawling."
 * In the Droopy cartoon "The Three Little Pups", Droopy is watching television with his two brothers in one scene; Wolfie tries to suck them up with a giant straw, only to grab the television instead (and end up with it lodged in his stomach). Two scenes later, Droopy and his brothers are watching television again, and Droopy  looks at the camera and says, "Now don't ask us how we got the television set back..."

Real Life
"Alice: Hey, Bob... Oh, it doesn't matter. Bob: What? Alice: *uses this trope* Bob: No, go on, tell me. (Alice's muddy hands go in Bob's face)"
 * These words are often the verbal equivalent of Schmuck Bait. Unless someone has been taught --repeatedly—to avoid it, people will almost invariably try to find out what they shouldn't know. They are also a major reason Aesop Amnesia is Truth in Television.
 * Does anyone know this joke?


 * How 75-year-old Sally from America's Got Talent Portland discovered she could hand-whistle. She wrote a book about it, but.
 * Judging by how the judges on the show reacted ('mm-hmm'-ing and nodding), they evidently didn't consider the above to be an example of the trope. It could be a bit of a Mood Whiplash, though.