History Main / INeverSaidItWasPoison

* In ''Anime/YuGiOh'', "Bandit" Keith Howard accuses Joey of using someone else's entry card to qualify for the semi-finals of Pegasus' tournament, in a bid to get Joey disqualified after losing to him. Joey freely admits that he was given his current entry card by Mai Valentine after losing his original one... but Keith had no reason to know that unless he was trying to sabotage the other competitors' progress through the tournament by stealing their entry cards. Pegasus, who already knows that Keith was cheating during his duel against Joey, has Keith ejected from the tournament instead.

* ''ComicBook/IdentityCrisis'': Used when [[spoiler:Jean Loring]] mentions the note at Jack Drake's crime scene to [[spoiler:Ray Palmer]], despite Batman removing the note from the scene before the press found out. Oops.

-->'''Kira''': P-Please hurry up and heal me!\\
'''Josuke''': Hurry? Oh? No matter how you slice it, I look like an [[JapaneseDelinquent average high schooler]]... so why are you asking me to heal you? It's hard enough for me to get into pachinko parlors... [[SpottingTheThread yet you think I look old enough to be a doctor that graduated into medical school?]] Huh?\\

-->'''Milton:''' Do you know how many actors I've worked with? Hundreds, thousands.\\

--> '''Vetinari:''' And, indeed, some rumours about the death of young Mr. Dearheart last month.
--> '''Horsefry:''' There is no proof that we had anything to do with the boy's murder!
--> '''Vetinari:''' Ah, so you too have heard people saying he was murdered? These rumours just ''fly'' around, don't they...

--->'''Goku:''' I'm actually looking for the person who blew up a galaxy.
--->'''Paragus:''' But who would blow up South Galaxy?

-->'''Mulder''': We're here to investigate a string of suicides at your military base.\\
'''Colonel Wharton''': I don't know about any voodoo revenge murders.

-->'''Alexandra''': I never said anything about aswang Mr. Mayor.

* Sei Arisaka does this in ''Manga/HimechanNoRibon'' by saying that he knew who Pokota was even though Hime-chan had never told him, which is how she realised there was something more to him than originally thought.

* In chapter 4 of ''[[https://archiveofourown.org/works/34188727/chapters/86129611#workskin Tales of the Mysterious and Miraculous Kitty-Whiskers Soot-Fur, and... Ladybug]]'', Trucy as Kitty-Whiskers visits her uncle Valant Gramarye to see if he was the one who gave her and Apollo their Miraculouses. When asked about the Miraculouses, Valant says that his magic involves illusions and not with the kwami... despite the kwamis never being mentioned to the public before. Of course, Kitty-Whiskers knowing that the Gramarye family is connected with the Miraculouses clues Valant in that the hero before him is his niece, [[SecretKeeper though promises to not tell anyone else]] and offers to lend the Bee and Fox Miraculouses if she needs them in the future.

* INeverSaidItWasPoison/AnimeAndManga
* INeverSaidItWasPoison/FanWorks
* [[INeverSaidItWasPoison/LiveActionFilms Film — Live-Action]]
* INeverSaidItWasPoison/{{Literature}}

* INeverSaidItWasPoison/VideoGames

[[folder:Myths & Religion]]
* The Cranes of Ibycus is a classic example of this trope, making it OlderThanFeudalism. According to a legend first recorded in the 2nd century BCE, the ancient Greek poet Ibycus was murdered by bandits on his way to Isthmian Games. Only the cranes flying above witnessed the murder. Later the criminals gave themselves away by pointing out "The Cranes of Ibycus" to one another in public.

[[folder:Professional Wrestling]]
* The following storyline has been done several times in ProfessionalWrestling: A babyface wrestler is late to the building, possibly even showing up after the match he's advertised in has already started without him. He explains to the crowd that he's late because of ''a'' flat tire. His adversary gets on the mic and says the babyface is simply a coward who made up some story about ''four'' flat tires, which exposes that the adversary slashed the tires of the babyface.
* In All Out 2021, with his originally scheduled opponent Pac unable to attend due to travel issues (which had plagued Pac and the Lucha Bros. beforehand, all of which were implied to have been caused by Andrade), Andrade and Chavo Guerrero Jr. were interviewed backstage. After having been asked point blank if they were the cause of Pac's travel issues, Chavo quickly interjected that he didn't even know the number for American Airlines, and then quickly backtracked and said "if that's the flight he was using."

[[folder:Visual Novels]]

* A kidnapping suspect in ''VisualNovel/KaraNoShoujo'' admits that he has some relation to the person witnessed actually taking the person away before the name of the person is revealed. Woops.
* [[spoiler:Souma Miou]] is outed as the one who had been bullying Rizu in ''VisualNovel/AProfile'' because when confronted with a little evidence blurted out the location the evidence had been found in.

* ''WebAnimation/Supermarioglitchy4sSuperMario64Bloopers'': In [[Recap/Supermarioglitchy4sSuperMario64BloopersIfMarioWasAMONGUS "If Mario was AMONG US"]], Mario realizes [[spoiler:Brown]] is the Impostor when he mentions that Mario and Green were in a room with an open vent... a room he shouldn't have been in.

[[folder:Webcomics]]

** This is how Sigma gets [[spoiler:Dio]] to reveal they were the one who [[spoiler:planted the bombs]] in some of the routes. Sigma reveals, from information he gathered [[spoiler:from time jumps]], that this person knows about the Myrmidons, and about Brother. [[spoiler:Dio]] insists they don't know anything about ''who'' the Myrmidons are, and they don't know anything about some ''old fart'' like Brother. Well, Sigma never actually mentioned the Myrmidons were people or that Brother, their leader, was an old man, so how would [[spoiler:Dio]] know that... unless the Myrmidons sent them?
** Subverted at another point of time when the players discover [[spoiler:Alice's]] body. When Dio says that the victim was stabbed with a knife Phi asks how did he know it was a knife when all they can see is a handle. Dio, however, points out that anyone would assume it was a knife if they saw someone with a weapon protruding from a stab wound. [[spoiler:Although this makes sense, Phi was still right to be suspicious, since he knew about the knife because it was ''his'' knife. But he's not the killer.]]

* This was how WFAA sportscaster Dale Hansen managed to trap three officials at Southern Methodist University into admitting they were still paying players on their football team. Hansen had gotten an envelope from a former SMU player who had alleged that he'd been paid by the program and that the envelope had money in it. Hansen then showed the envelope to the officials, and at first, administrator Henry Lee Parker admitted that he'd sent the envelope, but then immediately backtracked, as did the other two officials. At this point, Hansen knew the allegations were true because he'd never mentioned to Parker what had allegedly been in the envelope. Until then, all he had was the word of the former player (David Stanley). If the officials hadn't sent money, they wouldn't have backtracked from their original admission. This eventually led to SMU's football program being given the NCAA's "Death Penalty", resulting in the cancellation of their next two seasons and severe restrictions on their program like limits on coaching hires which so devastated the previously-successful program it took them over twenty years to play in another postseason bowl.

[[folder:Films — Live-Action]]
* ''Film/FourteenOhEight'': Used lightly when Mike Enslin calls a hotel for a reservation in the eponymous room, which the staff says is unavailable, despite not knowing ''when'' he'll be visiting, since they don't want anybody staying in the room ever. Actually could be a rare example of InvertedTrope, since it is not ruled out that they were consciously performing a ReversePsychology trick to get Mike in.
* In ''Film/AloneWithHer'', the tip-off that the protagonist has planted surveillance cameras in the house of the girl he's courting is when she rejects him and he starts ranting: "...I did everything for you, but you want to go back? To what? Huh? To being alone? To this empty room? '''To that brush'''?" Earlier in the movie, he'd caught a live feed of her masturbating with the hairbrush.
* A deleted scene in ''Film/AustinPowers'' involves Austin asking about "Mr" Evil (as well as Mr Pepper). Naturally, the FemmeFatale he's questioning replies with "Dr Evil" and "Dr Pepper" respectively.
* ''Film/BadGenius'': When Pat describes Bank, he lets slip that [[spoiler:Bank was beaten up and found in a landfill. The problem? Bank never told anyone he was found in a landfill -- only someone involved with beating him up would. He quickly deduces that Pat was responsible for it]].
* In ''Film/{{Basic}}'', this is subverted when Hardy is chatting with Styles about the death of [[spoiler:Kendal]]. Styles says something about [[spoiler:Kendal]] being poisoned, and Hardy immediately starts asking him how Styles would know that. Styles points out that one minute [[spoiler:Kendal]] was fine and the next he was coughing up blood before dying for no apparent reason, so poison is a reasonable guess under the circumstances. [[spoiler:DoubleSubverted mere moments later, when Hardy keeps acting suspicious of Styles and trying to poke holes in his story. Styles continues trying to bluff his way out for a minute or two before he gives up and tries to bribe Hardy (who had a reputation for being a DirtyCop), into silence.]]
* ''Film/BasicInstinct'': The cops try to invoke this when they go to question Catherine Tramell and her girlfriend Roxy about her boyfriend's murder, asking "How did you know he was murdered?", but it fails miserably, as both women point out that the men have identified themselves as ''homicide'' detectives and that it's the most natural conclusion to come to.
* In ''Film/{{Becky}}'', Dominick is interrogating Becky about his missing property over the walkie-talkie:
-->'''Becky:''' I don't have your stupid key!\\
'''Dominick:''' I never said it was a ''key''.
* In ''Film/BeyondAReasonableDoubt'', Tom and Susan are giddy with relief after Tom has been cleared of the murder of Patty Gray, hours before he was scheduled to be executed. Tom offhandedly wonders who killed "Emma". The fact that Patty Gray's real name was Emma Blucher is still a secret. Susan, who knows that secret, realizes that Tom is guilty after all.
* In ''Film/TheBigClock'', George Stroud was already suspicious of Steve Hagen, but he becomes convinced that Hagen is involved with the coverup of Pauline's murder when he mentions that Pauline was killed at 12:30 a.m. while providing an alibi for Earl Janoth. Not only should Hagen not have known the time of the murder at all, but Stroud knows that Pauline was still alive at 1:00 a.m., and only someone involved in [[ClockTampering changing the clocks]] in Pauline's apartment would claim she was murdered at 12:30.
* ''Film/{{Cheetah}}'': A brother and sister visiting their parents in Kenya adopt an orphaned cheetah cub whom they call Duma. When they have to return to the U.S., they plan to train her to hunt and release her back into the wild, but she disappears the night before they were going to leave. As their parents are driving them to the airport the next morning, they stop at the local general store where the owner says that it must be a sad day for the kids: leaving Kenya, losing their pet... the brother immediately jumps on this, asking why he thinks Duma is "lost". The store owner insists that by "lose", all he means is "releasing back into the wild where you will probably never see her again", but the brother is convinced that the owner wouldn't have used the word "lose" unless he knew about Duma's disappearance, and the only way he could know about the disappearance is if he was involved. [[spoiler:He's right.]]
* In ''Film/TheCountOfMonteCristo2002'', Mercedes realizes that the mysterious Count really is Edmond when he tells her that "Edmond Dantes is dead." She had told him that her lover Edmond was dead, but not his last name.
* ''Film/{{Dave}}'': Ellen Mitchell finds out Dave is impersonating her husband after mentioning something Bill Mitchell did in the state legislature (which he wasn't part of) and Dave confirms.
* ''Film/TheDaVinciCode'': Played with in the film adaptation. In an early scene, when Fache still suspects Langdon of murdering Jacques Sauniere (but hasn't yet told Langdon that he's a suspect), Langdon's extensive knowledge of art gets him into trouble when he says that Sauniere was murdered in the Louvre's Grand Gallery before Fache actually tells him where the body was found. Langdon ''actually'' knew because he recognized the Grand Gallery's distinctive parquet floor in a crime scene photo, but Fache has a hard time buying that excuse.
* In ''Film/TheDeparted'', [[TheMole Billy Costigan]] narrowly escapes being ambushed by the rest of the gang during a meeting with his handler and pretends to have arrived late after they have killed Queenan. After a shootout with police staking out the building, Delahunt, mortally wounded in the gunfight, [[spoiler:and who may be an undercover cop himself]], privately tells Costigan that even though he accidentally gave the wrong address for where the informant was going to be, Costigan was at the right one.
* ''Film/DoctorStrangeInTheMultiverseOfMadness'': [[spoiler:When America Chavez is attacked by a creature they determine to be born of witchcraft, Doctor Strange visits Wanda for help and at first they seem to be on board with working together. However, Wanda [[WhamLine offers to "keep America safe"]] and Strange immediately pauses because he never said her name was America, [[OhCrap which she also realizes and mentally kicks herself for.]] It all goes downhill from there.]]
-->[[spoiler:'''Wanda:''' ''(realizes her mistake)'' You never told me her name, did you?\\
'''Strange:''' [[TranquilFury No. I didn't.]]]]
* ''Film/TheFabelmans'': When Sammy Fabelman reveals to Claudia Denning that her boyfriend Logan Hall--his bully--cheated on her with Renee--though Sammy doesn't know her name and that it wasn't the first time, Logan threatens Sammy to force him into retracting it and saying he lied. Sammy ends up doing just that to Claudia with both her and her best friend Monica Sherwood--Sammy's future [[LoveInterests Love Interest]]--grilling him about it. Claudia then however reveals she actually is sure Sammy was telling the truth before by following it up with the inquiry as [[ArmorPiercingQuestion to how Sammy knew Renee had red hair to begin with]].
* In ''Film/TheFugitive,'' a hospital worker Dr. Kimble spoke to slips up with SuspiciouslySpecificDenial, claiming he hadn't seen Kimble before the Marshal even asks.
* In ''Film/TheGodfatherPartII'', Michael realizes that Fredo betrayed him when they were in a sleazy Cuban nightclub, and Fredo says "Watch this part of the act, it's really something", even though earlier Fredo had told Michael that he had never been to Cuba before. Fredo also mentions how "old man Roth" would "never come here", but that Johnny Ola showed him the place, despite an earlier claim of never having met either Roth or Ola before, and both Fredo and Ola acting as if they were being introduced for the first time to one another just previously. Actually kind of a double Inversion since Michael never tries to trip him up, but not being very bright, Fredo just blurts it out. The look of betrayal on Michael's face is classic and a definite example of {{Foreshadowing}}.
* ''Film/HarryPotter'':
** In the ''Film/HarryPotterAndTheChamberOfSecrets'' movie, Dobby the house-elf repeatedly does this, accidentally admitting to having [[spoiler:intercepted letters from Harry's friends, sealing the entrance to Platform 9¾, and bewitching a Bludger to attack Harry]], although the last two may have been intentional.
** In the ''Film/HarryPotterAndTheGobletOfFire'' movie, a disguised Death Eater blows his cover by mentioning the graveyard Harry was sent to before Harry does. The Death Eater in question may not have cared at that point, though.
** In ''Film/FantasticBeastsAndWhereToFindThem '', one of the first hints that [[spoiler:Graves]] isn’t who he says he is is when Newt gets arrested for having an Obscurius parasite, he says that the parasite is [[spoiler: useless without its host]], prompting Newt to respond [[spoiler: that it killed an innocent little girl and what would it be ''used'' for?]]
* ''Film/{{Highlander}}'': Subverted. Lieutenant Moran, the lead detective investigating the beheading of Iman Fasil, tries to get Connor [=MacLeod=] to implicate himself using this sort of technique ''twice'' in the same conversation, but it doesn't work either time.
-->'''Moran:''' Okay. What's that? ''[indicates the plastic-wrapped Toledo Salamanca on his desk]''\\
'''Connor [=MacLeod=]:''' ''[who knows exactly what it is]'' A sword?\\
'''Moran:''' It's a Toledo-Salamanca broadsword worth about a million bucks.\\
'''[=MacLeod=]:''' So?\\
'''Moran:''' So you want to hear a theory? You went down that garage to buy this sword from that guy -- what's his name?\\
'''[=MacLeod=]:''' ''[who also knows who Iman Fasil was]'' I don't know. You tell me.
* In ''Film/HighSchoolHellcats'', a girl dies in a (seemingly accidental) fall down a staircase at an illicit party, and the teenage partygoers try to cover up the fact that they were involved. When the girl, Connie, has been missing for several days, a detective comes in to question her classmates individually. Everyone claims they haven't seen her and don't know where she is. The detective happens to ask one of them if the missing girl had any enemies, and receives the response that "No, everyone liked Connie. She was a regular guy." The detective immediately seizes on [[SuspiciouslySpecificTense the use of the past tense]]. (It doesn't help that the girl being interviewed explodes into a sudden screaming fit when confronted by this. She later [[StupidCrooks gloats about pushing Connie down the stairs to a third girl]] she's trying to kill to cover it up, even though as far as anyone knew, she was only guilty of the same comparatively minor crimes as the other kids.)
* ''Film/ISpitOnYourGrave'': In the third film, Ron at first denies ever having raped his stepdaughter Cassie after Jennifer kidnaps him. She notes he'd yet to hear Cassie's name from her, revealing his guilt.
* ''Film/JackReacher'': Inverted when a former sniper is accused of going on a killing spree. He's badly beaten in prison and experiences amnesia about the last several days, not remembering the incident. The titular character has already determined that the sniper was set up, since no professional sniper would pick that parking garage and would, instead, shoot from a van on the nearby bridge. When the accused finally regains consciousness and freaks out because he believes himself guilty (he previously did go on a killing spree while in Afghanistan but got off because the men he killed turned out to be rapists). The DA shows him pictures of the area and asks him how he would have done it. He gives the same reply as Reacher, confirming to the DA that he didn't do it.
* ''Film/JaggedMind'': As a result of hearing Alex say Rose slit her wrists, which Billie didn't say, thus Billie's made aware that she'd somehow been involved with Rose's death. It turns out that Alex murdered her, making it [[NeverSuicide look like a suicide]].
* ''Film/TheJinx'': When Robert Durst is asked what divers would be looking for in the lake behind his former house, Durst blithely replies "body parts", rather than "a body". The specific detail of the former statement seems to foreshadow later events or could have been how he would have said it anyway.
* ''Film/KnightMoves'': Subverted. The protagonist knows the latest word in the serial killer's message without being told directly because the killer namedropped a chess master and the word is that master's watchword.
* ''Film/LAConfidential'': Ed Exley likes doing a variant of this in his [[PerpSweating interrogations]]. In particular, he tends to say something about the person he's interviewing being guilty as if it were a fact, and note that the person doesn't react the way an innocent person would. For example, in his first interrogation, he tells the perp "It's a shame you didn't pull this a few years ago when you were a minor, you being an adult makes it a gas chamber offense." Later, after he's done and is leaving the room, he stops to say, "You know Ray, I'm here talking about you getting the gas chamber, and you never asked me what this is about. You've got a big guilty sign around your neck." The kicker in particular case is that [[spoiler:the guys he's interrogating are guilty of something heinous but not of the crime he's investigating.]] A different interview gives us this exchange.
-->'''Exley:''' [[{{Blackmail}} What do they have on you]], Loew? Pictures of you and Matt Reynolds with your pants down?\\
'''D.A. Ellis Loew:''' ''[hesitates]'' Do you have any proof?\\
'''Exley:''' [[LeaveNoWitnesses The proof had his throat slit]]. And so far, you're not denying it.
* ''Film/LethalWeapon3'':
-->'''{{Mook}}:''' Like I told you before, asshole, I don't know no [[DirtyCop Jack Travis]]!\\
'''Riggs:''' Hey, I didn't say his name was "Jack" -- you'd better start telling me more than Jack Shit.
* The 1971 giallo film ''Film/ALizardInAWomansSkin'' has an example. A free and libertine woman named Julia is brutally murdered in her apartment; the suspicion falls on her neighbor, Carol, a wife of Frank, a promising lawyer whose father is a prominent politician and a lawyer himself. The evidence points to Carol, who is promptly arrested, yet the police inspector, unable to find any clear motive, suspects a more complex possibility. Carol had some personal troubles and was seeing a psychoanalyst, who asked her to keep a diary of her vivid dreams; some dreams included a passionate love affair with Julia and one recent dream described Carol brutally slaying her. The inspector thinks that someone read the diary and modelled the crime on her dreams while planting the evidence. In the climax, the inspector meets Carol, telling her the evidence suggests her father killed Julia when she started blackmailing him with the evidence of Frank's infidelity, threatening to expose the evidence and ruin the reputation of a law firm Frank and his father ran together, then committed suicide to save Carol when she was committed to an asylum. Carol says she knew that because Julia phoned her father with a blackmail offer. The inspector asks how did she know that, since the man never talked about the blackmail to anyone but Frank in private after Carol was already committed. Suddenly, he realizes the simplest solution was right all along: Carol ''did'' have a passionate affair with Julia and murdered her when threatened with exposure - Julia made her call just before being slain and only the killer could have known what the call was all about.
* In ''Film/MacheteKills'', [[spoiler:Miss San Antonio]] accidentally reveals they are a double agent when they mention the missile being in Texas. Machete then asks how they knew the missile had been moved from Mexico.
* ''Film/MaskedAvengers'': TheMole is revealed when he mentions one of his victims being killed with a spear, even though the protagonist said nothing about that, and just said the victim was attacked.
* In ''Film/{{Matilda}}'', Miss Honey makes a visit to Matilda's parents, to express how bright she is. When her parents laugh this off, making several jabs at educated people, Miss Honey tries to describe how an educated person would treat them in a hospital, or, say, defend them in court if they were accused of selling a faulty car. Mr. Wormwood, who does partake in such a shady business, replies "What car? Sued by who? Who you been talking to?"
* ''Film/MinorityReport'' has the villain realize the protagonists are onto him when he's caught in one of these. [[spoiler:Anderton's wife asks about Anne Lively's death, and Burgess pretends not to know about it but says he'll see if "anyone drowned a woman by the name of—what did you say her name was?". "Anne Lively... but I never said she drowned."]]
* In ''Film/MurderIsMyBeat'', Patrick questions the suspect Eden's roommate Patsy, telling her only that he's investigating a homicide. When Patsy correctly guesses that Frank Dean was the victim, Patrick says, "Who said Dean was the victim?" Patsy replies, "You. You were the one who was talking about him all evening." Patrick is still suspicious and says, "Jumped to a quick conclusion, didn't you?" [[spoiler:Sure enough, Patsy turns out to have been involved in the {{blackmail}} operation that led to the man's death, although she didn't kill him.]]
* ''Film/MyBloodyValentine3D'': [[spoiler:Tom]] when he says that the message written in blood above Megan's body was the same one she had written in her Valentines card to Axel. Sarah then asks how he knew that Megan was dead, or what was written above her body.
* In ''Film/NewTownKillers'', the protagonist Sean is offered a large sum of money by two businessmen for them to hunt him throughout the city until either they kill him or he survives the night. At one point he goes to hide out at his friend Sam's house and tells him there are guys trying to kill him. Sam later mentions the two guys. "I never said there were two of them."
* In ''Film/OlympusHasFallen'', Mike Banning is a Secret Service agent who is apparently the only free survivor of an attack on the White House by Korean terrorists. He then comes across another survivor and fellow Secret Service agent who claims to have been hiding during the whole attack, but during their conversation mentions "This Kang guy is insane" referring to the leader of the attack. Banning then realizes that there's no way he could've known Kang's name if he was indeed hiding out in the White House the whole time and correctly deduces that he is a traitor working with the terrorists.
* ''Film/PatriotGames'': A version of this is used after Jack Ryan's IRA informant gives him pictures of the people who had attempted to kill Ryan (and in a separate attack, his wife and daughter). Jack's superior dismisses the information, believing that mole is trying to mislead Jack. "All he has to do is show you a few pictures of a girl..." Jack realizes he never told the man he was looking for a female assassin and realizes the information must be legitimate.
* ''Film/ThePoliceAreBlunderingInTheDark'': When the photographer realizes who must be responsible for the disappearance of the girls who modeled for him, he immediately confronts the culprit. The culprit in turn claims to believe that it’s ''the photographer'' who was driven by twisted psychology to murder the women. However, only the killer knows where the bodies went…
* ''Film/PrimalFear'': Played with. Aaron is a suspect charged with murdering a Catholic Cardinal. The played with part comes in [[spoiler:when Aaron appears to have multiple-personality disorder and doesn't remember what his other personality, named Roy, does. It helps him beat the first-degree murder charges for an insanity verdict. During the trial, Aaron turns into Roy and he attacks the prosecutor while he's on the stand. This causes a mistrial and the judge to find him insane. After the trial, arrogant defense attorney Martin Vail, who begins to feel sorry and care for Aaron, feels proud of himself, only for Aaron to let a detail slip (possibly intentionally) that only Roy would know: Roy attacking the prosecutor. It's at this point that Aaron confesses that he never had multiple-personality disorder and faked his Aaron personality to con everybody.]]
* In ''Literature/PrimaryColors'', Jack Stanton is accused of fathering a child with a 17-year-old girl. His wife explains to him that she doesn't think he's the father; however, the fact he tried to find out suggests he had a relationship with her.
* In ''Film/TheProwler1951'', Susan is pretty much convinced that Webb murdered her husband John, but is in denial about it. However, when Webb slips and mentions the exact amount of John's life insurance policy, she can can no longer lie to herself and has to acknowledge that Webb's act was premeditated.
* ''Film/RedEye'': Although the protagonist never realizes it and the film never makes a point of it later on, early in Jack ends up letting slip the name of the protagonist's father, which at that point she had never told him.
* ''Film/RehearsalForMurder'': The murderer gives themselves away by revealing that they knew Monica had a flashlight in her dresser drawer: something only someone who was in her bedroom on the night she died could have known.
* In ''Film/ReindeerGames'', when everything's seemingly over [[spoiler: and Rudy, Ashley, and Gabe -- the survivors of the casino robbery -- have gathered, Ashley mentions Rudy's cellmate Nick was stabbed with a shiv... but Rudy only told her his cellmate was killed; he never told her ''how''. A few moments later, a now-doubting Gabe gets offed by Ashley, and Nick turns out to have [[NotQuiteDead been hiding]]...]]
* In ''Film/TheRockyHorrorPictureShow'', when Brad asks if he can use the phone, Frank smirks into the camera and comments on Brad and Janet getting a flat tyre, even though Brad never mentioned it. Though Brad doesn't pick up on this. Theatre productions vary on how meaningful this detail is, as any of the motorcyclists passing by on their way to the castle could have mentioned the unoccupied car. Some directors do try to establish there was a car-trap on the road, either to get random passersby [[spoiler: for fresh body parts if necessary]], Brad and Janet specifically [[spoiler: for their connection to Dr. Scott, although this colours his own arrival]], and in one instance the original trap was replaced by a tyre-puncturer by one of the guests in an attempt to somehow incriminate Riff-Raff and Magenta after the play's normal ending. The movie leaves it unclear if Frank is just amused at this.
* In ''Ruby Herring Mysteries: Her Last Breath'', when Ruby confronts the killer with her suspicions, her theory is further confirmed when the killer names the specific poison used on the victim when that information hasn't been revealed to the public.
* In the third ''Film/RushHour'' film, Carter and Lee deliver Genevieve to [[spoiler:Minister Reynard]]. He orders her to take off her wig and show him the Shy Shen list tattooed on her head. Lee whispers to Carter that they never told him she was the list, revealing that [[spoiler:Reynard]] is working for the Triad.
* ''Film/{{Scream}}'':
** In ''Film/Scream3'', when John Milton tries to play down his connection to Rena Reynolds [[spoiler:a.k.a., Sidney Prescott's Mom]].
-->'''Milton:''' Do you know how many actors I've worked with? Hundreds, thousands.\\
'''Gail:''' Dewey didn't say she was an actor...
** ''Film/Scream4'': [[spoiler:Jill's]] master plan falls apart once she comments about having a similar wound to [[spoiler:Gail]], a fact only the latter's attacker could know.
* In ''Film/{{Selfless}}'', after undergoing shedding and waking up in the new body, Damien starts experiencing hallucinations of a woman and a child. Albright explains that the hallucinations are probably just a combination of Damien getting used to the new body and having past memories getting jumbled. The Latino woman he's seen is probably a woman he used to date and forgot. Damien points out that he never said the woman was Latino.
* ''Theatre/{{Sleuth}}'': Subverted; Wyke mocks Inspector Doppler for trying this tactic on him, pointing out that he hasn't said anything that wasn't an obvious inference from what Doppler ''had'' said.
* The inverted form occurs in ''Film/SomeGuyWhoKillsPeople''. Sheriff Fuller is convinced Ben is making a FalseConfession, and talks to him about the notes the killer sent: saying he found the one reading "I am a monster" particularly chilling. Ben says "Thank you", and Fuller then tells him that there never was a note reading that. The "I am a monster" note was from the 'Son of Sam' case.
* In ''Film/SuddenDeath'', one of the villains gives himself away by mentioning Darren's daughter by name when Darren had only told him he has a daughter and that she's being held hostage. He immediately {{Lampshade|Hanging}}s his mistake.
-->Damn it. I always do things like that. You never said her name, did you?
* Mario and Luigi are already suspicious of Koopa in ''Film/SuperMarioBros1993'' when he tries to play a lawyer, but it only intensifies when he asks about the meteorite piece they got from Daisy, which he'd have no reason to know about.
* In ''Film/TheTerrorOfTinyTown'', Bat Haines tells Nancy that Tex has been murdered before anyone except the murderer could have known that he was dead.
* In ''Film/TomorrowNeverDies'', [=MI6=] becomes suspicious of corrupt media mogul Elliot Carver's involvement in a diplomatic incident between the UK and China when his newspaper, ''Tomorrow'', reports certain details of the incident (such as the British corpses being machine-gunned with the same type of ammo issued to the Chinese air force) before British Intelligence was able to confirm them.
* At the end of ''Film/TransformersRiseOfTheBeasts'', [[spoiler:Noah is in the middle of a job interview and is having trouble relating his experiences from his time with the Autobots and Maximals to the interviewer without sounding irrational. Then, the interviewer specifically asks him about his time in Peru, to which Noah remarks that he never brought up which country he was abroad in. The interviewer reveals that the US government has been aware of what Noah has been doing the entire time and wants to thank him for his actions by not only giving him access to the healthcare his younger brother needs but by also giving Noah a position within a clandestine organization of which the interviewer is a member. He then reveals that the room they are is a front for a hangar containing Cybertronian artifacts and gives Noah a card with information about the organization in question: ''Franchise/GIJoe'']].
* In ''Film/WildChild'', when Poppy is before the Honour Court for setting fire to the school, [[spoiler: head girl Harriet accidentally reveals that ''she'' was actually the one who started the fire by talking about the very specific lighter that Poppy supposedly used, when no one has mentioned anything about a lighter.]]
* In ''Film/{{Wishmaster}}'', Alex becomes suspicious that the Djinn is impersonating Professor Derleth when the professor mentions Alex's boss, only for Alex to point out that she had never told the professor where she worked.
* ''Film/TheWomanInTheWindow'': Played straight so often that it stops being suspenseful and becomes hilarious; the guilt-ridden professor lets slip every possible detail, including knowing the man was murdered (when the body hadn't turned up yet), knowing where the body was placed, that it happened at night, etc. His friends are so dense that they wave off every comment and never suspect him, but you would think he'd just learn to keep his mouth shut, especially when having casual conversations ''with the district attorney''.
* ''Film/WomanOnTheRun'': Only the killer, the detective, and Eleanor know that the murderer shot at Frank but missed because he was aiming at his shadow. Danny inadvertently gives this slight information away, tipping Eleanor off right away that he's the murderer.
[[/folder]]

* INeverSaidItWasPoison/Literature

[[folder:Literature]]
* At the end of the ''Literature/AToZMysteries'' book ''The Lucky Lottery'', the three main kids confront their prime suspect over a stolen lottery ticket.
-->'''Ruth Rose:''' And ''your'' fingerprints are on the mantel where you stole the Christmas card!
-->'''Dot Calm:''' You're crazy, kid. I was wearing glov...
* In one of the minor adventures the protagonists have while traveling from place to place in ''Literature/TheBalancedSword'', they're asked to investigate a murder, and the murderer gives himself away by mentioning a detail he shouldn't have known.
* ''Literature/BenSnow'':
** In "Frontier Street", the murderer gives himself away when he says how many times the victim had been struck over the head: something he would not have been able to tell just from looking at the body.
** In "The Man in the Alley", Ben realises that the mastermind behind the assassination UsefulNotes/WilliamMcKinley is [[spoiler: Arthur Plenty]] because [[spoiler:his editorial mentions the exact price Leon Czolgosz paid for the gun he used before Czolgosz had confessed all the details. Ben knew the price because he had been tailing Czolgosz when he bought it, but Plenty could only have known if he was the person who provided the cash]].
** In "Brothers on the Beach", the killer slips up when they mention that they didn't have someone holding the wingtip steady during the first attempted flight of the Wright Brothers Flyer, which was when the murder occurred. However, the killer had gone some trouble to establish an alibi of not being present at the first attempt, and shouldn't have known what Orville and Wilbur did or didn't do.
* ''Literature/{{Brotherband}}'': Hal and his band ensnare Zavac by telling the Korpaljo, the leader of the town they're in, that Zavac is hiding their share of plundered emeralds in his hold, from the mines in Limmat. When the Korpaljo interrogates Zavac:
-->'''Zavac:''' "That's not true! I was never anywhere near Limmat!"\\
'''Korpaljo:''' "Who said anything about ''Limmat?''"
* ''Literature/BrotherCadfael'': The inversion happens in the third book, ''Monk's Hood''. The prime suspect (the victim's stepson) thinks the murder was a stabbing when it was actually a poisoning.
* Creator/JohnDicksonCarr:
** Creator/JohnDicksonCarr made one of the greatest examples of this trope in his novel ''The Emperor's Snuff-Box'', in which the killer's guilt is revealed by a small piece of information which obviously showed they had information they could only have known were they the killer, but which is accepted without question. At the beginning of the book, protagonist Eve Neill is suddenly visited by her ex-husband Ned Atwood in the middle of the night. While they are arguing, Ned looks out of Eve's bedroom window (which has a curtain drawn over it) and claims to see her future father-in-law, Sir Maurice Lawes, handling a "snuff-box thing" when somebody walks into Lawes' study. Later, they both see Sir Maurice with his head bashed in, the snuff-box smashed to bits, and a gloved hand turning off a light. Atwood later falls down a flight of stairs into a coma, causing Eve's testimony to become unsupported. [[spoiler:We later learn Sir Maurice had bought the snuff-box earlier that day, showing it off to his family. The snuff-box had the facade of a pocket-watch, and Lawes had written about it in a journal on his study desk. At the book's end, it is revealed that Atwood, from the distance he "saw" Sir Maurice with the snuff-box, could not have known it was a snuff-box due to its watch-facade, and that the only way he could have known it was that he had killed Sir Maurice himself, smashed the snuff-box without ever seeing what it looked like, and discerning its nature from seeing the words "snuff-box" written in Sir Maurice's journal. Since Atwood had convinced Neill she had seen Sir Maurice alive herself, she had repeated this testimony and convinced the police for awhile that she had lied and killed him.]]
** ''The Emperor's Snuff-Box'' also has another version of this trope, in which another suspect is found to be lying about seeing the light through the closed door of Sir Maurice's study [[spoiler: when the carpeted floor would not allow light through, in order to hide the fact that they were trying to steal one of Sir Maurice's antiques when they found Sir Maurice already murdered.]]
* In one of Creator/AgathaChristie's short stories, a man is killed by a blow on the head with a bronze statue. Two of the suspects--his wife and her lover--both confess to the crime: she says that she shot him, and he--that he stabbed him with a small dagger. On further interrogation, both tell that they assumed the other one was guilty and so lied to protect each other. [[spoiler:But actually this trope is [[InvokedTrope invoked]]: they are ''both'' guilty. They have planned the murder together and made the false confessions to make the police believe them to be innocent.]]
* ''Literature/{{City of Bones|1995}}'' by Creator/MarthaWells: When Khat, Sagai, and Elen question the academia scholar about the BlackMarket relics they think he bought, they know his denials are false when he says he never had anything to do with a "fourth [[FantasticCasteSystem tier]]" dealer--they hadn't mentioned the dealer's social standing.
* Reversed in Creator/TomClancy's ''Literature/ClearAndPresentDanger'', when the FBI is investigating the mistreatment of prisoners on a Coast Guard ship. He says that one of the prisoners was executed (he wasn't, but they staged an execution by hanging to get a second prisoner to confess everything) to which the captain replies "We captured two prisoners, we gave you two prisoners alive, so who did we shoot?"
* ''Literature/TheCrownerJohnMysteries'': In ''The Sanctuary Seeker'', a suspect gives himself away when he says he has never heard of the victim Aelfgar of Totnes. John had said the victim was named Aelfgar, but not that he came from Totnes.
* In the short story "Death of the King" by Theodore Mathieson, UsefulNotes/AlexanderTheGreat is dying, not of sickness as the historical records will claim, but of poison. He and his physician are trying to find out WhodunnitToMe, [[spoiler:until the physician offers Alexander a cushion "for the great pain in your back", and the emperor realises he knows more about how this poison works than he admitted]].
* In Creator/KatherineKurtz's ''[[Literature/{{Deryni}} The Quest for Saint Camber]]'', a member of the secretive Camberian Council is found dead in a secret passageway of the king's palace. In a conversation with Nigel (King Kelson's uncle/regent/heir presumptive), his eldest son Conall says the victim's entire name, which the younger man is not supposed to know. Nigel realizes Conall had been secretly working with the dead man (to obtain arcane powers reserved for the monarch) and killed him in that stairwell; Conall attacks his father with those powers and leaves him in a coma.
* ''Literature/DesertStar'': Subverted. Detective Renee Ballard zeroes in on Nelson Hastings as the killer because Hastings said he didn't remember any black people volunteering for the Pearlman campaign, when Renee never told him that murder victim Laura Wilson was black. However, when Renee confronts Hastings with this gotcha, he says he looked up "Laura Wilson murder Los Angeles" on the internet and found a news story with Wilson's picture. And as it turns out, Hastings didn't do it.
* ''Literature/{{Discworld}}'':
** In ''Literature/GuardsGuards'', Lupine Wonse's immediate response to Vimes reporting the destruction of the Elucidated Brethren's headquarters was a suspiciously specific "Any of them get out?" Because Vimes was distracted, he doesn't pick up on this until a EurekaMoment later on.
** ''Literature/FeetOfClay'':
*** Inverted when Carrot becomes sure that Dorfl didn't kill Dr. Hopkins when he agrees to Carrot's statement that Dorfl beat him to death with an iron bar, when in fact he was killed with a loaf of [[IndestructibleEdible dwarf bread]].
*** Played straight later in the book, when Vimes figures out how the Patrician was being poisoned, with arsenic in candles. He confronts the vampire he suspects being behind it, as well as many other suspicious events, and knows he is guilty when he implies the vampire got ATasteOfHisOwnMedicine and sees him glance at the candles in the room, despite having no way of knowing how Lord Vetinari was being poisoned.
** Played with in ''Literature/{{Night Watch|Discworld}}''. After an antagonist officer tells Vimes of a break-in, Vimes asked what had been stolen. The other officer tries to invoke this trope, replying "Did I say they stole anything, sir?" and Vimes shuts him down with "Well, no, you didn't. That was me jumping to what we call a ''conclusion''. Did they steal anything, then, or did they break in to deliver a box of chocolates and a small complimentary basket of fruit?" (Although to be fair to the officer, Discworld is home to anti-crimes such as 'breaking and ''decorating'''.)
** Crispin Horsefry in ''Literature/GoingPostal'' has habit of protesting his innocence even when not directly accused of anything. When Vetinari has a meeting with him and the other "investors" in the Grand Trunk clacks system, Horsefry insists everything they have done is perfectly legal, and even drops this glaring clanger:
--> '''Vetinari:''' And, indeed, some rumours about the death of young Mr. Dearheart last month.
--> '''Horsefry:''' There is no proof that we had anything to do with the boy's murder!
--> '''Vetinari:''' Ah, so you too have heard people saying he was murdered? These rumours just ''fly'' around, don't they...
** Vimes uses it in ''Literature/{{Thud}}'' when talking to the Troll crime boss Chrysoprase. Chrysoprase lets slip that his knowledge of a crime scene is greater than what the public would know. When Vimes calls him out, Chrysoprase dismisses the accusation as gossip that he heard from the Dwarfs. Or well, had Dwarfs beaten up or threatened until they told him. He did, in fact, have no connection to it.
** ''Literature/MakingMoney'' uses this in a rather meta way. Moist is being interrogated by [[ObfuscatingStupidity Carrot]], all while under the guise of being an upstanding pillar-of-the-community businessman. When he tries to shut Carrot down due to him, Moist, being aware of this trope...
--->'''Moist:''' Look, [[LampshadeHanging I know how this sort of thing goes]]. You just [[PerpSweating sit here and ask questions]] and eventually, I slip up and [[DiscussedTrope reveal something incriminating]], right?\\
'''Carrot:''' Thank you, sir.\\
'''Moist:''' For what?\\
'''Carrot:''' For telling me that you know how this sort of thing goes, sir.
* In Creator/OrsonScottCard's ''Literature/EndersShadow'':
** [[BigBad Achilles]] slips up and tells the other orphans that Poke [[EyeScream had been stabbed in the eye]], when he couldn't possibly know that. Nice show, Achilles, nice show.
** Colonel Graff does a slip up on the phone to Bean's caretaker (a very intelligent nun) when he says the name Bean told him about, Achilles (pronounced uh-kill-eez). The nun points out that since Bean is from the French section of Rotterdam he would have pronounced it ah-sheel and correctly calls him out for spying on Bean's journal.
* In the ''Literature/FatherBrown'' short story "The Green Man", the victim is an Admiral who is found dead in a pond close to his home, on the evening when he was expected to return home from a longer sea voyage. Upon being told that the Admiral is drowned, the murderer asks: [[spoiler: "Where was he found?"]] which tips off Father Brown. Note that Father Brown is older than radio. If the Admiral had drowned at any time during the voyage, his family would probably not have found out until his ship came back to England. [[spoiler: Unless you know that he drowned in the pond, the reasonable thing would have been to assume that the body was lost at sea.]] Father Brown bites his tongue at the actual tip-off, but this trope comes into play in the big reveal at the end.
* ''Literature/FelseInvestigates'': Played with in ''Death and The Joyful Woman'' by Creator/EllisPeters. Kitty confides in Dominic that she intends to confess to the murder; seeking to dissuade her, he tells her exactly why she couldn't have done it, because her story fits the vague description of the murder the police have made public, but not the reserved details he knows of through his father, the chief investigator. Too late, he realises he'd have done better to keep quiet: if she'd tried to confess, the police would have known she was innocent by the same reasoning, but now she actually knows details the police haven't made public, she's in danger of making the police think she's guilty. Which is exactly what happens.
* In one of the ''Literature/FireThief'' trilogy, the Avenger almost pulls this off and discovers the boy he is talking to is helping Prometheus when the boy mentions the shopkeeper looking for a spade (to dig up some buried treasure). But the boy quickly says he was running down the street shouting "half a million dollars for a spade."
* In ''Literature/HanSoloAtStarsEnd'', Han finds that one of the three rebels he's transporting has murdered their leader, who just managed to scrawl the name of the destination planet, Mytus VII, in the table in front of him before he died. Han figures out who the traitor is by [[spoiler:telling each one separately that he suspects another, and then telling them they're going to Mytus VIII, IX or X. He gets them all together, supposedly to research the target, and makes them show their datapads; the traitor is the one who mentally corrected it to the planet he already knew was the real destination]].
* ''Literature/TheHauntingOfAlaizabelCray'': Used near the beginning -- the hero finds a young woman in the part of London infested by gribbly things, and asks the governor of a local mental asylum if he's lost any patients- he mentions her being found in the Old Quarter, despite not being told. In this case, it could be a reasonable assumption but the hero decides to be careful and gives a false description- [[spoiler:a good idea, since said governor is part of the cult that had captured the girl...]]
* This trope comes into play at the climax of ''Hope Never Dies'' by Andrew Shaffer. Amateur detective UsefulNotes/JoeBiden (just [[MST3KMantra roll with it]]) has retrieved a cache of drugs, and is on a train back to Delaware to hand it over to the authorities, when his FriendOnTheForce intercepts him and sits down to compare notes. He mentions [[spoiler:how fentanyl's potency makes it extremely valuable, gram for gram--enough that a fortune's worth could be hidden in an energy-drink can. It's plausible enough that he knows the drug being smuggled is fentanyl. The problem is, he has no ''[[DirtyCop legitimate]]'' way of knowing that Biden is carrying just such a can in his duffel bag...]]
%%* ''Literature/InDeath'': Used at some point or another in ''almost every single book'' in the series.%%How?
* ''Literature/JaineAustenMysteries'':
** Jaine clues in that [[spoiler:Pam]] is the killer in ''The PMS Murder'' after stating Rochelle talked to a building inspector on the day of the murder, despite Jaine never mentioning a building inspector. This is because [[spoiler:Pam ''was'' that building inspector]].
** Sam Weinstock mentions that Jaine fixed the terrible hairdo Gustavo Mendez gave her in ''Death by Pantyhose''. Jaine notices she never mentioned where she got the crappy haircut, and Sam then reveals she set it up to drive Andrew Ferguson away from Jaine.
** In ''Death of a Neighborhood Scrooge'', Scotty's ex-wife Elise describes the murder weapon (a frozen chocolate yule log), even down to the writing on it [[note]]"Merry Christmas, Aunt Harriet". Scotty was [[TheScrooge ''really''' cheap.]][[/note]], which had not been mentioned in the media. Elise explains that she learned it from talking to Scotty's current wife, Missy, which Detective Muntner confirms.
* ''Literature/TheMazeRunner'': In ''The Scorch Trials'', while Thomas never mentions to Brenda that his group calls themselves [[spoiler:Gladers]], she ends up mentioning it in casual conversation. This foreshadows the fact that she and Jorge had actually been working for [[spoiler:WICKED all along; she most likely knows the term because she heard them call themselves that while she monitored the Maze]].
* ''Multiple Choice'', by Janet Tashjian, has the main character fall victim to this. Monica chooses to write something nasty about her best friend on the upstairs school bathroom's stalls. When confronted about it, she denies vehemently and convinces her friend that she wasn't the one who wrote it. As they walk away, she lets slip that "I'm never even up there"—despite her friend never saying which bathroom it was. A fight ensues.
* ''Literature/NeroWolfe'': In ''Literature/TooManyCooks'', [[spoiler:Raymond Liggett]] casually mentions the name of the sauce used in the taste-testing contest the chefs engaged in, despite supposedly being out of the state at the time and having no possible way of learning the information.
* ''Literature/NickVelvet'':
** In "The Theft of the Lopsided Cobweb", the killer gives themself away when they say Nick should be more careful when being shot at. As no one else was present, only the killer could know Nick was shot at.
** In "The Theft of the Picture Postcards", Nick deduces the identity of a blackmailer when they mention the amount of money demanded, despite the victim never mentioning it.
* ''Literature/PercyJacksonAndTheOlympians'': Ares falls victim to this in ''The Lightning Thief''; when Percy deduces that he's been taking orders from the thing in the pit, Ares angrily replies, "I'm the god of war! I take orders from no one! I don't have dreams!" when Percy didn't bring up dreams at all during his rundown.
* ''Literature/TheRadix'': Hunting for Wurm, an escaped asylum patient, Adriana Borjia interrogates Cori. After Cori says "I didn't see him", Adrianna smiles and says: "I never said the patient was a man". It isn't considered "him" is often the default, or that it wouldn't be a bad guess to assume that someone able-bodied enough to escape an asylum would be a man...
* In ''Literature/TheRobotsOfDawn'', Elijah discusses the matter of Jander's deactivation with Amadiro, and suddenly Amadiro states that the woman at whose house the RidiculouslyHumanRobot was had a very unusual definition of husband. While it might have made sense for him that the robot was her ''lover'' (it's a FreeLoveFuture), there is no way he could have figured out the ''husband'' part; for Aurorans, marriage is a union with a potential for kids, so a RoboticSpouse in totally ridiculous. As such, he manages to prove Amadiro was attempting a GrandTheftPrototype (he desperately needed such robots, and their designer refused to cooperate) by thoroughly questioning Jander, so the guy is forced to fold before the investigation destroys his career completely.
* A case of the villain inadvertently using this against the protagonist occurs in ''[[Literature/AlexRider Scorpia]]'', when Julia Rothman tells Alex that Scorpia intends to activate a bioweapon that will kill a significant portion of the population. Alex, knowing that the weapon is designed to specifically target schoolchildren, blurts out that they can't murder children, causing Rothman to realise that Alex is a triple agent for [=MI6=] and that [=MI6=] have figured out how the weapon operates.
* ''Literature/TheSherlockHolmesStoriesOfEdwardDHoch'': In "The Addleton Tragedy", one academic gives away their involvement in Dr. Addleton's death when they remark "I do not want my head bashed in, like Dr. Addleton"; not realising that, at the time, everyone believed Addleton had burned to death.
* ''Literature/SimonArk'': In [[spoiler:"The Avenger from Outer Space"]], the killer gives himself away when he mentions that the victim ''started'' to reach into the water with both hands. As the victim only had a burn mark on one hand, and the one witness did to the event not recall that detail, only someone else present at the scene could have known that detail.
* ''Literature/SmallChange'': In ''Farthing'', the murder victim appears to have been stabbed. The police forensic techs figure out that he actually died of carbon monoxide poisoning, but don't reveal this to the press. A bit later, one character reveals that they know that the victim was gassed.
* Creator/DonaldSobol:
** ''Literature/EncyclopediaBrown'': This happens quite a bit. Not generally for murders, but it happens.
*** One story had Encyclopedia figuring out which member of a gang robbed a grocery store, his only piece of evidence being a knife left stuck into a watermelon. When confronting the gang, one of the members says the blade of his knife is a half-inch longer... despite the knife never having been taken out of the melon, and the watermelon specifically having been described as "huge" so that even the longer knife blade would still be completely hidden. True to form, the member in question turns out to have been the robber.
*** Another Encyclopedia Brown story has someone getting shot in the foot by a BB gun. One of Bugs' friends shows up, and Encyclopedia tells him to run to the kid's house and get his shoe. The kid grabs the correct shoe, and Encyclopedia points out that unless he was the one who shot him, he couldn't have known which shoe to get. [[ConvictionByCounterfactualClue An innocent person would have had a 50 percent chance of guessing right]], but would probably have asked 'Which shoe?'
*** Another story had a pair of rollerskates stolen from Encyclopedia while the latter was at the dentist. He asks his main suspect (a kid who had a doctor's appointment in the same building) if he was in Dr. Vivian Wilson's office. The kid claims "I never heard of him until you mentioned his name" and that he didn't go near Wilson's office because he "had a sprained wrist, not a toothache". In other words, despite supposedly never having heard of him, the kid not only knew that Dr. Wilson was a dentist but that he was a man despite his [[GenderBlenderName first name being "Vivian"]].
** Also common in ''Literature/TwoMinuteMysteries'', by the same author—things like "Dr. Smith was murdered, where were you at the time?" "I haven't been to a dentist in years."
* ''{{Literature/Spenser}}'' gets one of several hints the Stapleton family in ''Small Vices'' is lying about their son and his alleged non-involvement in the case Spenser has been hired to investigate when they specifically refer to it as a sex crime, since the fact that the victim was also murdered was far more likely to be of note to people who had supposedly only heard of it in passing. Their referring to it only a sex crime makes sense when, at the end of the book, [[spoiler:it's revealed it wasn't actually a murder—the victim and their son were playing a sex game involving EroticAsphyxiation and she accidentally died during it.]]
* In ''Literature/StarTrekMillennium'', Vash knows exactly what neurotoxin ''she'' was attacked with without being told, alerting Bashir that she's pulling a WoundedGazelleGambit.
* ''Literature/TheThrawnTrilogy'': The last book, ''The Last Command'', features [[spoiler:Niles Ferrier attempting to accuse Talon Karrde of hiring an imperial assault team to attack a group of smugglers as [[FalseFlagOperation an example of the threat the Empire posed.]] He slips up when he mentions the name of the lieutenant leading the assault team ''before'' it's brought up by the person reading the planted evidence, [[GuiltyUntilSomeoneElseIsGuilty proving Karrde's innocence beyond a reasonable doubt]]. He nearly slipped up before that by mentioning that incriminating evidence was ''on'' the datacard before anyone announced it had been found, only for Ellor to immediately confirm it ''had'' been found.]]
* ''Literature/TheThreeInvestigators'':
** ''The Mystery of the Kidnapped Whale '' had a case involving a whale where a suspect accidentally blurted out its species. The person could not have known this at the time.
** On another occasion, someone asks what the "???" on their business card means. This is a OnceAnEpisode thing which wouldn't normally be significant, but one of the group notices that they didn't actually ''read'' the card, and must have seen it before.
* In the ''Literature/ThursdayNext'' book ''First Among Sequels'', Thursday and Spike accuse a plumber of stealing money from a pensioner. His boss joins in with the accusation, saying "A thousand pounds, from a defenceless pensioner? How ''could'' you?" Thursday and Spike had never mentioned the amount.
* This is how George Smiley discovers TheMole in the Secret Intelligence Service in Creator/JohnLeCarre's ''Literature/TinkerTailorSoldierSpy'': the man in question turned up at the Circus with not enough information about the unfolding Operation Testify crisis for him to have got it from the radio report, but too much to have overheard it from a phone conversation.
* In Creator/RuthFrancesLong's ''Literature/TheTreacheryOfBeautifulThings'', Jack tells Jenny that after [[RuleOfSeven seven]] long years, her brother was gone. But she only told him she was after her brother, not how long ago he had vanished.
* In "True Lies", a short mystery story starring Lieutenant Johnson and Sgt. Bolton, the genius detective sergeant has narrowed down the possible murderers to two, but doesn't know which one. Since he thinks his lieutenant partner (who is the {{Narrator}}, and who would be TooDumbToLive if he didn't know how to [[{{Masquerade}} hide it]] from his fellow cops) is the genius detective, and so is dependent on him for his own genius, he asks the lieutenant for the solution. Our narrator doesn't know and is eating dry granola, so he chokes and says (as an excuse) "Tense!" [[EurekaMoment This gives the sergeant the solution]]; the murderer was the one who referred to the victim in the past tense before it was generally known that she was dead.
* ''Literature/TwoKindsOfTruth'': [[spoiler:Terence Spencer tries to avoid a subpoena by telling the person delivering it he doesn't know a "Terry Spencer" but she points out she only called him "Mr. Spencer".]]
* In the ''Waco'' series by Creator/JTEdson, Waco uses this trick a few times to trip up a killer.
* ''Literature/TwoLittleGirlsInBlue'': When the FBI interview Norman Bond about the Frawley twins' kidnapping, they bring up his currently missing ex-wife, to which he snaps he had nothing to do with his "late" wife's disappearance. The feds take note of this, pointedly asking how he knows she's dead. While someone missing for seventeen years without a trace probably is dead in all likelihood, it makes Norman nervous. [[spoiler:It's later revealed he ''was'' responsible for his ex-wife's disappearance]].
* ''TabletopGame/Warhammer40000'': In Creator/GrahamMcNeill's ''Literature/HorusHeresy'' novel ''False Gods'', Loken knows that Erebus is lying to him because he pointed out that the interex had accused them of stealing a kinebrach's sword—and in fact, the interex had only accused them of stealing a weapon.
* ''A Widow For A Year'': Inverted when the policeman deliberately gives the press false information about a murdered prostitute, saying she was killed WITH a struggle when there was no struggle. This enabled him to dismiss the two men who confessed as they were covered in bruises and scratches.
* In ''Literature/WingsOfFire'', Tsunami and Starlight figure out that Blister killed [[spoiler:Kestrel]] when Blister tells Tsunami that she would have wanted to slash her mother's throat like what happened to [[spoiler:Kestrel]], even though she was only told that [[spoiler:Kestrel]] was stabbed by a [=SandWing's=] tail.
[[/folder]]

* [[https://en.wikipedia.org/wiki/Paul_Warner_Powell Paul Warner Powell]] killed a teenage girl and raped and attempted to stab her sister, and was sentenced to death. There was insufficient evidence that Powell had attempted to rape Stacie Reed before killing her, so he could not be convicted of [[UsefulNotes/ThreeDegreesOfMurder Capital Murder]] and the [[UsefulNotes/AmericanCourts Supreme Court of Virginia]] reversed his death sentence. So Paul believed he no longer faced a death sentence [[ArtisticLicenseLaw because of Double Jeopardy]], and he sent the prosecutor a taunting letter where he [[TooDumbToLive confessed, in detail,]] to attempting to rape Stacie before killing her. Becaise the court vacated his verdict instead of acquitting him, double jeopardy didn't apply, and so the letter [[HoistByHisOwnPetard was used by the Commonwealth to send him back to the electric chair]][[note]]His choice over lethal injection[[/note]]. He was named an [[http://darwinawards.com/stupid/stupid2003-01.html At-Risk Survivor]] by the Website/DarwinAwards.

* [[https://en.wikipedia.org/wiki/Paul_Warner_Powell Paul Warner Powell]] killed a teenage girl and raped and attempted to stab her sister, and was sentenced to death. There was insufficient evidence that Powell had attempted to rape Stacie Reed before killing her, so he could not be convicted of [[UsefulNotes/ThreeDegreesOfMurder Capital Murder]] and the [[UsefulNotes/AmericanCourts Supreme Court of Virginia]] reversed his death sentence. So Paul believed he no longer faced a death sentence [[ArtisticLicenseLaw because of Double Jeopardy]], and he sent the prosecutor a taunting letter where he [[TooDumbToLive confessed, in detail,]] to attempting to rape Stacie before killing her. Becaise the court vacated his conviction instead of acquitting him, double jeopardy didn't apply, and so the letter [[HoistByHisOwnPetard was used by the Commonwealth to send him back to the electric chair]][[note]]His choice over lethal injection[[/note]]. He was named an [[http://darwinawards.com/stupid/stupid2003-01.html At-Risk Survivor]] by the Website/DarwinAwards.

* [[https://en.wikipedia.org/wiki/Paul_Warner_Powell Paul Warner Powell]] killed a teenage girl and raped and attempted to stab her sister, and was sentenced to death. There was insufficient evidence that Powell had attempted to rape Stacie Reed before killing her, so he could not be convicted of [[UsefulNotes/ThreeDegreesOfMurder Capital Murder]] and the [[UsefulNotes/AmericanCourts Supreme Court of Virginia]] reversed his death sentence. So Paul believed he no longer faced a death sentence [[ArtisticLicenseLaw because of Double Jeopardy]], and he sent the prosecutor a taunting letter where he [[TooDumbToLive confessed, in detail,]] to attempting to rape Stacie before killing her. The letter [[HoistByHisOwnPetard was used by the Commonwealth to send him back to the electric chair]][[note]]His choice over lethal injection[[/note]]. He was named an [[http://darwinawards.com/stupid/stupid2003-01.html At-Risk Survivor]] by the Website/DarwinAwards.

* At the end of ''Film/TransformersRiseOfTheBeasts'', Noah is in the middle of a job interview and is having trouble relating his experiences from his time with the Autobots and Maximals to the interviewer without sounding irrational. Then, the interviewer specifically asks him about his time in Peru, to which Noah remarks that he never brought up which country he was abroad in. The interviewer reveals that the US government has been aware of what Noah has been doing the entire time and wants to thank him for his actions by not only giving him access to the healthcare his younger brother needs but by also giving Noah a position within a clandestine organization of which the interviewer is a member. He then reveals [[spoiler:that the room they are is a front for a hangar containing Cybertronian artifacts and gives Noah a card with information about the organization in question: ''Franchise/GIJoe'']].

* In UsefulNotes/VictorianBritain, seven members of the Marshall family were brutally murdered in their home in the village of Denham and the investigation lead to a man named John Owen. When an officer found and arrested him, he immediately declared "I have murdered neither man, women nor child" despite the officer having not had a chance to tell him what he was being arrested for and his having been out of town preventing him from having heard that he was a suspect.

* In ''WesternAnimation/IceAge: A Mammoth Christmas Special'', Manny told Sid he was going on Santa's naughty list, which didn't exist beforehand:
-->'''Santa Claus:''' Oh, look at this mess! Two hours to Christmas, and everything's ruined! My toys, my sleigh, all my hard work!\\
'''Sid:''' Um, would this be a good time to talk about getting off the naughty list?\\
'''Manny:''' Sid, there's no such thing.\\
'''Santa Claus:''' There is now, Manfred. [[NiceJobBreakingItHero Thanks for the idea.]] ''[Santa magically makes his first ever naughty list]''

* ''WesternAnimation/TheLittleMermaid1989'': When King Triton summons Sebastian to discuss Ariel's recent lovestruck behavior, [[OneDialogueTwoConversations Sebastian thinks the sea-king knows the]] ''[[OneDialogueTwoConversations whole]]'' [[OneDialogueTwoConversations truth]]: that she's fallen in love with a human. He soon cracks from the pressure and reveals Ariel's secret whilst begging for mercy, only to learn that Triton hadn't known after all.
-->'''Triton:''' ''(coyly)'' Sebastian... I ''know'' you've been keeping something from me.
-->'''Sebastian:''' Keeping... something?
-->'''Triton:''' About Ariel?
-->'''Sebastian:''' ''(his legs tremble)'' A-A-Ariel...?
-->'''Triton:''' ''In love?''
-->'''Sebastian:''' ''(hyperventilates)'' I TRIED TO STOP HER, SIR! She wouldn't listen! I told her to stay away from humans! They are bad, they are trouble, they...
-->'''Triton:''' ''Humans?! '''WHAT ABOUT HUMANS?!'''''
-->'''Sebastian:''' ...Humans? ''(nervous chuckle)'' Who said anything about humans?

* ''Literature/BrotherCadfael'': This happens in the third book, ''Monk's Hood''. The prime suspect (the victim's stepson) thinks the murder was a stabbing when it was actually a poisoning.

** Creator/JohnDicksonCarr made one of the greatest examples of this trope in his novel ''The Emperor's Snuff-Box'', in which the killer's guilt is revealed by a small piece of information which obviously showed they had information they could only have known were they the killer, but which is accepted without question. At the beginning of the book, protagonist Eve Neill is suddenly visited by her ex-husband Ned Atwood in the middle of the night. While they are arguing, Ned looks out of Eve's bedroom window (which has a curtain drawn over it) and claims to see her future father-in-law, Sir Maurice Lawes, handling a "snuff-box thing" when somebody walks into Lawes' study. Later, they both see Sir Maurice with his head bashed in, the snuff-box smashed to bits, and a gloved hand turning off a light. Atwood later falls down a flight of stairs into a coma, causing Eve's testimony to become unsupported. [[spoiler:We later learn Sir Maurice had bought the snuff-box earlier that day, showing it off to his family. The snuff-box had the facade of a pocket-watch, and Lawes had written about it in a journal on his study desk. At the book's end, it is revealed that Atwood from the distance he "saw" Sir Maurice with the snuff-box, could not have known it was a snuff-box due to its watch-facade, and that the only way he could have known it was that he had killed Sir Maurice himself, smashed the snuff-box without ever seeing what it looked like, and discerning its nature from seeing the words "snuff-box" written in Sir Maurice's journal. Since Atwood had convinced Neill she had seen Sir Maurice alive herself, she had repeated this testimony and convinced the police for awhile that she had lied and killed him.]]

* In ''Literature/DeathInTheClouds'', Literature/HerculePoirot mentions to the main suspect that fingerprints were found in a bottle of poison used to kill the daughter of the first victim. The suspect says that is impossible because he was wearing gloves.

* ''Film/TheFabelmans'': When Sammy Fabelman reveals to Claudia Denning that her boyfriend Logan Hall--his bully--cheated on her with Renee--though Sammy doesn't know her name and that it wasn't the first time, Logan threatens Sammy to force him into retracting it and saying he lied. Sammy ends up doing just that to Claudia with both her and her best friend Monica Sherwood--Sammy's future [[LoveInterests Love Interest]]--grilling him about it. Claudia then however follows up with the inquiry as [[ArmorPiercingQuestion to how Sammy knew Renee had red hair]].