History Main / HowDidYouKnowIDidnt

* [[http://dilbert.com/strips/comic/2010-12-29/ Alice]] in ''ComicStrip/{{Dilbert}}'' deduces that a coworker must either be an unhelpful moron or a robot sent to destroy the company from within and proceeds to tear his (robotic) head off. Dilbert asks how she knew it was the robot option... Knowing her, she probably didn't ''care''.

* In ''Fanfic/HuntersOfJustice'', [[WebAnimation/{{RWBY}} Team RWBY, Qrow]], and [[ComicBook/TheLegionOfSuperHeroes Saturn Girl]] are working with ComicBook/JonahHex to stop a train robbery being pulled by the time traveling thief Chronos. While riding on horseback among Chronos' {{Mooks}}, Ruby can't take the shot because she doesn't want to kill people if it can be avoided. Jonah wastes no time and shoots a mook in the head. The spray of oil reveals that they're MechaMooks dressed in period clothing. Being mindless drones, the heroes have no reservations in tearing them apart. When Qrow asks if Hex knew they weren't living people, the CombatPragmatist simply says he didn't.

* From ''ComicBook/FallenAngel'': This exchange after Lee drops Shadow Boxer off a roof and he lands in a hay truck.

* In ''Film/TheMechanic'', [[spoiler:Bishop and Steve]] are in a hotel room, sharing a bottle of wine, when [[spoiler:Bishop]] keels over. [[spoiler:Steve]] tells [[spoiler:Bishop]] that his glass had been coated with poison and he will be dead in a few minutes. [[spoiler:Bishop]] asks [[spoiler:Steve]] if he is doing this as payback for killing [[spoiler:Steve's father]]. He is actually surprised, and says, "You killed him? I thought he just died."

* In ''Film/TheMechanic'', Bishop and ==McKenna== are in the hotel room, sharing a bottle of wine, when [[spoiler:Bishop keels over]]. [[spoiler:==McKenna==]] tells him that [[spoiler: his glass had been coated with poison and he will be dead in a few minutes]]. [[spoiler: Bishop asks ==McKenna==]] if he is doing this as payback for [[spoiler:killing ==McKenna's== father]]. [[spoiler: ==McKenna==]] is actually surprised, and says, "You killed him? I thought he just died."

* Zig-zagged in Creator/TexAvery's "Dog Hounded", where Droopy proceeds to flummox the Wolf by being where he isn't supposed to be.

* In ''Literature/TheDayOfTheJackal'', Commissioner [=LeBel=] believes that a member of the French Cabinet is leaking confidential information to The Jackal. [=LeBel=] plays a tape of a telephone conversation to the entire Cabinet, showing that one of their members had been betraying them. As the meeting is breaking up, the Minister of the Interior asks him how he knew which one of their phones to tap. "I didn't, so I tapped all of them." Everyone is dumbstruck, even the Minister (which is unfair, since he gave [=LeBel=] unlimited authority in the first place).

* In the ''Series/Daredevil2015'' episode "[[Recap/Daredevil2015S1E4InTheBlood In the Blood]]", Karen Page goes to an auction where Union Allied assets are being auctioned off. While she's there, Ben Urich sits down behind her and tells her to avoid looking suspicious by bidding on some of the smaller lots. When they reconvene at the diner that they'd had a meeting at earlier in the day, Karen asks Ben how he knew she was there, and Ben replies, "I wasn't looking for you."

Can be disturbing when you realized that our hero [[MoralLuck had no problem killing someone and just happened to kill someone evil]]. Alternatively, sometimes the hero might have known the truth all along and just be yanking the chain of the person asking the question.

--->'''Bart:''' Dad! You killed the zombie Flanders!\\
'''Homer:''' He was a zombie?

* ''WesternAnimation/BatmanBeyond'': In "Babel", Bruce is telling Terry about an incident from his days as Batman:

* ''WesternAnimation/{{Futurama}}'' "The Deep South", the ship is sinking and taking on water. Fry rushes offscreen, we hear a toilet flush, and the water starts to drain away.

* In part 2 of the pilot for ''WesternAnimation/MyLittlePonyFriendshipIsMagic'', the main characters are attacked by a manticore. They fight back until [[FriendToAllLivingThings Fluttershy]] calls for them to stop, much to their surprise. She approaches the monster, nuzzles it, and the manticore reveals the source of its fury: a thorn in its paw. After she removes the thorn, the manticore lets them pass. Twilight Sparkle asks how Fluttershy knew about the thorn, and the pegasus replies that she didn't, but assumed the manticore just needed to be shown kindness.

** In one scene where Morty shoots Rick in the head. Then Rick shoots the villains to death while they're gloating and reveals Morty's gun had a label reading "FAKE GUN -- SHOOT ME IN STANDOFF". Morty nervously chuckles and says "[[BlatantLies Good thing I saw that note!]]"
** In "Total Rickall", Rick shoots Cousin Nicky, a memory-injecting parasite, killing it. When asked how he knew it was a parasite and not a real person, Rick says he guessed and had aimed at its shoulder for that reason.

** The "Treehouse Of Horror III" segment "Dial 'Z' for Zombie", Homer shoots an undead Ned Flanders (this is reported to be Creator/MattGroening's favorite scene from the entire history of the series).

** Another example from the "Treehouse Of Horror IV" segment "Bart Simpson's Dracula":
--->'''Grampa:''' (''holding a hammer and stake'') Quick! We must kill the boy!\\

'''Grampa:''' He's a vampire!? (''runs off screaming'')
* In the ''WesternAnimation/TeenTitans2003'' episode "Betrothed", Beast Boy turns into a non-Earth animal for the first time, specifically an alien seen earlier in the episode:

* ''WesternAnimation/UltimateSpiderMan2012'', "Blade":
-->'''Spider-Man:''' I see what you're doing. You sent [[ComicBook/LukeCage Power Man]] to punch a hole because you knew his invulnerability would protect him, right?\\

* ''WesternAnimation/BatmanBeyond'': Bruce is telling Terry about an incident from his days as Batman:

** The Halloween episode "Dial 'Z' for Zombie", Homer shoots an undead Ned Flanders (this is reported to be Creator/MattGroening's favorite scene from the entire history of the series).

** Another example from another Halloween episode:
--->'''Grampa:''' ''[holding a hammer and stake]'' Quick! We must kill the boy!\\

'''Grampa:''' He's a vampire!? ''[runs off screaming]''

* The player gets an opportunity to have his own How Did You Know? moment in the (chronological) beginning of ''VideoGame/MaxPayne2TheFallOfMaxPayne''. No game mechanic prevents you from killing an innocent bystander at a crime site, a cleaner. In fact, you will be rewarded for doing so by him not leading you into an ambush.
** Max himself gets one when he [[spoiler:shoots his partner when she confronts him and his fugitive love interest.]] Only later does he actually find any evidence that [[spoiler:she was going to kill them both by order of the big bad.]] Max, ever the melodramatic sort, states that thinking for even a moment that the future revelation justified his prior actions damns him just that much more.
* A similar example in ''VideoGame/DeusEx''. If you kill a [[spoiler:doorkeeper at the gates of the cemetery housing Dowd's crypt]] on sight, the guy will later turn out to be a spy, and [[spoiler:Dowd]] will even praise you for being just the right type of trigger-happy paranoiac they need.
** ''[[VideoGame/DeusExHumanRevolution Human Revolution]]'' has a similar case where one way to complete a sidequest is to knock out or kill two drug dealers, but gives a special response if you had done so already after being given their names (unlike Dowd, though, Tindall just thinks you're overly violent).
* ''VideoGame/AssassinsCreedI'' had Al Mualim and Altair using almost these exact words during one of their discussions. Al Mualim asking and Altair answering.
* The popular gamemode for the ''VideoGame/HalfLife2'' mod ''VideoGame/GarrysMod'' titled "VideoGame/TroubleInTerroristTown" revolves around trust/mistrust in a town full of terrorists, 1 in 5 of which are united traitors, seeking to kill the innocent terrorists, similar to the Mafia game people play on forums/IRC/at social gatherings. Occasionally someone gets shot for no real reason, is accidentally pushed off a high ledge, or get just plain unlucky and die suddenly when they're a traitor. The result is an upset traitor, and a confused, but happy group of innocent terrorists who have one less threat to deal with. Especially funny when playing with friends who you actually know, rather than random players.

* ''VideoGame/MurderInTheAlps'': When Anna Myers and Judit Halle interrogate [[spoiler:Gustav Meisner]] in ''The Dada Killer'', Judit bluntly tells him she knows [[spoiler:he fathered the unborn baby of the murdered Wilma Sommer]], which he confirms to be true. When Anna afterwards asks Judit how she knew this, she admits she simply had a hunch.

* ''Webcomic/CyanideAndHappiness'' [[http://www.explosm.net/comics/2481/ #2481]] the man in the green shirt saves a woman from choking.
-->'''Blue Guy:''' Wow! Good thing you knew the Heimlich maneuver!\\
'''Green Guy:''' What's the Heimlich maneuver?
* Now-defunct ''VideoGame/SonicTheHedgehog'' sprite comic ''Webcomic/InSonicNia'' has a story where an evil version of Sonic comes to the main universe. Eventually, he angers Shadow, who kills him, leading to this exchange:
-->'''Knuckles:''' But how did you know it wasn't the real Sonic?\\
'''Shadow:''' That wasn't the real Sonic?
* In ''Webcomic/KevinAndKell'', when the Tidewater Pitchforks gardening team is on strike, one of the strikers worries about the dry crops. Carl says to stay firm. In the next panel, rain begins. They say the name of this trope.

* In the ''WesternAnimation/TeenTitans2003'' episode "Betrothed", Beast Boy turns into a non-Earth animal for the first time, specifically an alien seen earlier in the episode:
-->'''Cyborg:''' How did you know that you could do that?\\
'''Beast Boy:''' ''[having transformed back]'' Lucky guess.
* In a ''WesternAnimation/XiaolinShowdown'' episode where Kimiko is fighting an [[RobotMe evil robot duplicate of herself]], Omi jumps high in the air and takes one of the Kimikos out in one swipe. The defeated robot explodes, but, when asked about how he knew which one was which, Omi admits to having guessed. Not quite as extreme as the page description otherwise implies, since if he'd kicked the real Kimiko, she'd have probably just rubbed her kicked spot and been annoyed... not actually exploded.
** This really surprised Clay and Rai though because up until that point, Omi knew ahead of time every trick thrown at him throughout the episode thanks to his Tiger Instinct, including Rai's [[RunningGag constant attempts through Shen-Gong-Wu battles and card dealings]]. When he said that he "guessed" that time, they were aghast he didn't/couldn't use his Tiger Instinct.
* ''WesternAnimation/TheSimpsons'':
** The Halloween episode "Dial 'Z' for Zombie", Homer shoots an undead Ned Flanders (this is reported to be Creator/MattGroening's favorite scene from the entire history of the series).
--->'''Bart:''' Dad! You killed the zombie Flanders!\\
'''Homer:''' He was a zombie?
** Another example from another Halloween episode:
--->'''Grampa:''' ''[holding a hammer and stake]'' Quick! We must kill the boy!\\
'''Marge:''' How do you know he's a vampire?\\
'''Grampa:''' He's a vampire!? ''[runs off screaming]''
* ''WesternAnimation/{{Futurama}}'' "The Deep South", the ship is sinking and taking on water. Fry rushes offscreen, we hear a toilet flush, and the water starts to drain away.
-->'''Leela:''' Fry, you did it!\\
'''Fry:''' ''[reenters, zipping up pants]'' Did what?
* ''WesternAnimation/MegasXLR'': "The Driver's Seat" Coop accidentally teleports his Big Glug into a critical component of the Glorft mothership.
-->'''Gorrath:''' How did that primitive know where to hit us?!
* ''WesternAnimation/RobotChicken'': In the ''WesternAnimation/YellowSubmarine'' meets ''Film/TheHuntForRedOctober'' [[http://video.adultswim.com/robot-chicken/ping-them-back.html sketch]], Ringo didn't know the hole would stop the missile from hitting the Blue October; he was still on acid and said whatever came to him.
* The ''WesternAnimation/WingCommanderAcademy'' cartoon has an example where, faced with a Kilrathi carrier, the commander decides to play chicken with it. This works, and the carrier retreats.
-->'''Recruit:''' How did you know that they would retreat before we rammed them?\\
'''Commander:''' I didn't.

* In part 2 of the pilot for ''WesternAnimation/MyLittlePonyFriendshipIsMagic'', the main characters are attacked by a manticore. They fight back until [[FriendToAllLivingThings Fluttershy]] calls for them to stop, much to their surprise. She approaches the monster, nuzzles it, and the manticore reveals the source of its fury: a thorn in its paw. After she removes the thorn, the manticore lets them pass. Twilight Sparkle asks how Fluttershy knew about the thorn, and the pegasus replies that she didn't, but assumed the manticore just needed to be shown kindness.
* ''WesternAnimation/FamilyGuy'':
** This exchange after [[LovableSexManiac Glenn Quagmire]] saves a woman who is having a heart attack while changing at the mall:
--->'''Woman 1:''' That was amazing!\\
'''Woman 2:''' You saved her life!\\
'''Woman 3:''' Thank God you know CPR!\\
'''Quagmire:''' ''[confused look]'' What the hell's CPR?
** Also the basic frame of this trope is present in a joke in the (same) episode where Peter is blind. After Peter saves Horace from a burning building, he is asked how he found the courage to risk his life inside said burning building:
--->'''Peter:''' That freaking place was on fire?!
* A variant occurs in one episode of ''WesternAnimation/VoltronLegendaryDefender'', Lance and Keith are in a control room in the Balmera, trying to close the hatch. At one point, Keith puts his hand on the handprint and the hatch closes. Lance asks him how he did, and Keith responds that he doesn't know.
* ''WesternAnimation/ScoobyDooMysteryIncorporated'', "The Dragon's Heart":
-->'''Mr. Blake:''' But how did you know she would step in the middle of the boat?\\
'''Fred:''' I didn't. That's why I set up traps all over this place!

* ''WesternAnimation/TheSecretSaturdays'': Happens in "Black Monday" when Drew attempts to shoot her MirrorUniverse counterpart in the face with the Claw, only to have her doppelganger parry it with her prehensile tongue.
-->'''Zak:''' How did you know she could do that?\\
'''Drew:''' I didn't. I just wanted to hit her in the face.

* ''WesternAnimation/UltimateSpiderMan2012'', "Blade":
-->'''Spider-Man:''' I see what you're doing. You sent [[ComicBook/LukeCage Power Man]] to punch a hole because you knew his invulnerability would protect him, right?\\
'''Blade:''' He's invulnerable?
* Zig-zagged in Creator/TexAvery's "Dog Hounded", where Droopy proceeds to flummox the Wolf by being where he isn't supposed to be.
-->'''Wolf:''' How did ya get here, anyway?!\\
'''Droopy:''' Now, let's not get nosy, bub.
* Invoked in ''WesternAnimation/TheBatman'' where Batman punches an old lady florist (actually a PlantPerson guarding Poison Ivy's lair). Batgirl is surprised Batman knew she was a fake. Batman is [[TheStoic silent as usual]] as Batgirl continues questioning.

* ''WesternAnimation/BatmanBeyond'': Bruce is telling Terry about an incident from his days as Batman:
-->'''Terry:''' How did you know Robin would get there in time to save you?\\
'''Bruce:''' I didn't.\\
'''Terry:''' Then for all you knew, you were walking into a trap with no way out.\\
'''Bruce:''' [[TrapIsTheOnlyOption Sometimes you have to.]]
* ''WesternAnimation/TheHairBearBunch'': In "The Diet Caper," Hair's alibi for the animals raiding Peevly's refrigerator is because it was Botch's birthday. Peevly grudgingly buys it and orders the bears to clean up the kitchen.
-->'''Bubi:''' Boy, it's a good thing you remembered Botch's birthday, Hair. That was a real [unintelligible]. You saved our necks.\\
'''Hair:''' Who remembered? I made it up.\\
'''Square:''' You're joshin'!\\
'''Bubi:''' Yeah, but Botch didn't blow the whistle on you.\\
'''Hair:''' How could he blow the whistle? ''He'' doesn't remember when his birthday is either!
* WesternAnimation/DangerMouse tricks the Demon of the Fourth Dimension ("Demons Aren't Dull") into returning him and Penfold to their own dimension by invoking a clause in the Demons' union rule book:
-->'''Penfold:''' Lucky you remembered those union rules.\\
'''D.M.:''' No, Penfold. Lucky ''he'' didn't. I made them up. I fooled him.

* ''WesternAnimation/{{Amphibia}}'': When the town is attacked by a giant fire-breathing chicken monster, Mayor Toadstool uses Toadie's petrified body to block its flames. When Anne compliments his quick thinking, Toadstool's response is a surprised "Wait, he's ''stone''?"

%% Image chosen via crowner in the Image Suggestions thread: https://tvtropes.org/pmwiki/crowner.php/ImagePickin/ImageSuggestions150
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* An extreme example occurred in ''Manga/{{Saiyuki}}'' when the entire group sans Gojyo decide that the next time they see Gojyo, they'd beat the crap out of him for leaving their group and throwing off the dynamic. They meet an evil doppelganger Gojyo and naturally start to beat the crap out of it. When they discover it isn't Gojyo, they decide to pretend it is and proceed to tear it to shreds as a catharsis. Especially funny because the guy disguised as Gojyo fully expected them to pull the "[[ShapeshifterGuiltTrip How can I bring myself to fight my friend?]]" act... [[GoodIsNotNice Ehehe.]]
* On ''Manga/YuYuHakusho'' Yusuke is faced with a SpotTheImposter predicament and is told he has to punch the culprit as hard as he can to expose him. He narrows it down to two, and correctly chooses Kuwabara, but only did so because punching Kuwabara would make him feel the least bad if he was wrong.

* On the way to the Hunter Exam in ''Manga/HunterXHunter'', Kurapika hits Leorio in the face with his nunchucks. "Leorio" then transforms into a monstrous creature and asks how Kurapika knew he was an imposter. Kurapika responds that he didn't know, he just wanted to hit Leorio in the face. (Because Kurapika assumed that Leorio had abandoned the wounded man he had promised to take care of.)
* How L manages to pinpoint Kira's location in ''Manga/DeathNote''. L only had a few assumptions about Kira: that he can kill people without being present, that he won't tolerate being called out, and that the earliest death possibly related to Kira happened in Kanto, Japan. Thus, L decides to fake a worldwide Interpol announcement, with a criminal posing as L and taunting Kira. The announcement would only be broadcast in one place at a time, so that when the criminal is killed (presumably by a pissed-off Kira), L would know where he lives in. Not only was the plan almost instantly successful, but L was positively ''baffled'' at how flawlessly it went, beside himself at having already caught Kira in what was initially just supposed to be a ''test run''.

** The IDW reboot pulls it off without the double. Duke cold-clocks Snake-Eyes as soon as he appears during a mission off sheer suspicion, and it turns out to be Zartan. Duke says he didn't ''need'' to actually know: There was no way he could've hit the ''real'' Snake-Eyes.
%%* A variant occurred in the comic book ''ComicBook/SpyBoy''.

* From ''ComicBook/FallenAngel'': This exchange after Lee drops Shadow Boxer off a roof and he lands in a hay truck.
-->'''Slate:''' Pretty impressive, by the way. Timing Boxer's falling into that truck so he wouldn't be hurt.\\
'''Lee:''' ''[{{beat|Panel}}]'' What truck?

* In ''[[ComicBook/NewAvengers The New Avengers]]'', Dum-Dum Dugan shoots Victor Creed in the head:
-->'''Victor:''' So... They told you about my [[HealingFactor healin' factor]].\\
'''Dum-Dum:''' He heals?
* In issue #1 of the original ''ComicBook/NewWarriors'', Night Thrasher drops Richard Rider off a rooftop in order to re-activate his Nova powers (which Richard thought he'd lost after returning to Earth... long story). You can guess what Nova's next question and Night Thrasher's response are.
* In ''ComicBook/AvengersAcademy'' #25, Hazmat blasts X-23 with a toxic blast after X-23 stabs Mettle:
-->'''Giant-Man:''' Careful! Her healing factor isn't as strong as Wolverine's!\\
'''Mettle:''' You knew she'd survive that, right?\\
'''Hazmat:''' Yeah. Woulda done it anyway.
* In the ''ComicBook/BuffyTheVampireSlayer'' tie-in comic "Ring of Fire", Kendra attacks a man who turns out to be a demon. Xander asks how she knew. She didn't.
* In one issue of ''ComicBook/TheBatmanAdventures'', The Riddler is up to his old tricks, but another group of devious criminals is operating. So Batman is forced to choose which rogue to chase after and decides to go for the other party than bother with Riddler's obligatory riddle. By ''sheer coincidence'', both sets of Rogues hold their heists in the same building, allowing Batman to catch both. When Riddler asks how Batman solved his riddle, Batman just tells him, "I didn't" and Riddler is so happy to think he stumped Batman that he goes to jail singing a jaunty tune.
* This exchange occurs right after the Franchise/{{Ghostbusters}} finished dealing with a haunting in New Mexico during the "Haunted America" arc of the ''[[ComicBook/GhostbustersIDWComics IDW comics]]'':
--->'''Peter:''' And how did you know [[spoiler:telling the aliens they weren't aliens]] would work, Ray?\\
'''Ray:''' That? Oh, I didn't. I just guessed.\\
'''Peter:''' ...[[DopeSlap *THWACK*]]
* In ''ComicBook/MightyMorphinPowerRangersShatteredGrid'', [[BigBad Lord Drakkon]] sneaks into [[Series/PowerRangersRPM Corinth]] and confronts Dr. K while his forces are attempting to invade. During the confrontation, he makes the mistake of hitting K's BerserkButton over [[spoiler:the creation of the Venjix Virus]], causing Dr. K to haul out a cannon and blast Drakkon, revealing him to be a robot double. When the other Ranger Series Operators arrive, Scott asks how she knew it wasn't a real person. The murderous look on her face suggests she didn't and she ''didn't care''.
* ''ComicBook/UltimateXMen'': A non-verbal one during "Sinister". Scott's taken hostage by an arms dealer and fires his beam at Colossus. It bounces off Piotr's head and knocks the hostage-taker out, causing Piotr to ask how Scott knew his beams would reflect off Colossus' skin. Scott just changes the subject.
* In ''ComicBook/JonSableFreelance'' #5, Sable and a courier named Cynthia are fighting at the ends of ropes dangling from a hot air balloon, and the two ropes have gotten twisted around each other. The balloon is losing altitude and they need to lose weight so Sable's ally Milo cuts one of the ropes, sending Cynthia plunging to her death. After they have landed, Jon asks Milo how he knew which rope to cut and Milo walks away, without answering.

[[folder:Films -- Animation]]

[[folder:Films -- Live-Action]]
* ''Film/TheUntouchables1987'': How Ness [[spoiler:persuades the judge at UsefeulNotes/AlCapone's trial to change the jury he suspects has been bribed into returning a "not guilty" verdict]]. Doubles as a BatmanGambit.
-->[[spoiler: '''District Attorney:''' What did you tell him?]]\\
[[spoiler: '''Ness:''' I told him his name is in the ledger too.]]\\
[[spoiler:''[close-up of the Judge, staring daggers at Ness from the bench]'']]\\
[[spoiler: '''District Attorney:''' His name wasn't in the ledger...]]
* ''Film/MenInBlackII'': [[LaserGuidedAmnesia Amnesiac]] Agent K shoots alien pawn-shop clerk Jeebs in the head. [[RunningGag Again]].
-->'''J:''' You're back.\\
'''K:''' No.\\
'''J:''' How'd you know [[ImmortalLifeIsCheap his head grows back]]?\\
'''K:''' It grows back?
* In ''Film/TheNakedGun 2½: The Smell of Fear'', Frank Drebin is being "honored for his 1000th drug-dealer killed." He responds: "Thank you. But, in all honesty, the last two I backed over with my car. Luckily, they turned out to be drug dealers."

* ''Film/{{Unforgiven}}'' actively subverts a scene from ''Film/TheOutlawJoseyWales'' in which Wales survives an assault from a dangerous posse, then explains how he carefully chose which member he had to shoot first based on a SherlockScan of which one was the most dangerous. In ''Unforgiven,'' after Munny survives a similar encounter, he just shrugs and says that he got lucky when asked.
* In ''Film/Papillon1973'', the titular character takes shelter in a leper colony after his escape and is invited to share a cigar by their leader. Despite his fear of catching the disease, Papillon does so. There's a moment of silence from the leader (who clearly expected him to refuse) before he asks how Papillon knew he had dry leprosy, which isn't contagious. When Papillon replies that he didn't know, it breaks the ice between the two men.

* In ''Literature/TheDayOfTheJackal'', Commissioner [=LeBel=] believes that a member of the French Cabinet is leaking confidential information to The Jackal. [=LeBel=] plays a tape of a telephone conversation to the entire Cabinet, showing that one of their members had been betraying them. As the meeting is breaking up, the Minister of the Interior asks him how he knew which one of their phones to tap. "I didn't, so I tapped all of them." Everyone is dumbstruck, even the Minister (which is unfair, since he gave [=LeBel=] unlimited authority in the first place).
* In ''Film/TheJackal'', the FBI Deputy Director has been led to believe that someone in the FBI has been leaking information to the Jackal. He does the same thing to get a tape of a phone conversation recorded on a tapped line.
* The question is reversed in ''Film/{{Splice}}'' when [[spoiler:Elsa asks Clive if he knew that Dren had water lungs the whole time. He lies and says yes when he was actually trying to drown her]].
* In ''Film/KeepingMum'', after Gloria and her daughter Holly learn in short order that the new housekeeper is a paroled murderer who killed again and is also Gloria's long-lost mother:
-->'''Gloria:''' Aren't we forgetting the small matter of dead bodies?\\
'''Rosemary:''' How did you know about the other bodies?\\
'''Gloria:''' What other bodies?\\
'''Rosemary:''' ''[relieved]'' Oh, you didn't know about the other bodies.
* ''Film/DiamondsAreForever'': A Mafia {{mook|s}} throws Plenty O'Toole, one of the Bond girls, off of a high floor, and she lands unharmed in a swimming pool below. When Bond compliments him on his aim, the mook replies, "I didn't know there was a pool down there."
* In ''Film/PiratesOfTheCaribbeanOnStrangerTides'', Blackbeard forces Jack to play a variant of RussianRoulette with four unloaded pistols and two loaded ones, and Angelica (his daughter, Jack's love interest) as the target. When Jack takes the option to jump instead, Angelica asks her father if he knew which guns were loaded. He (unconvincingly) says he did, but considering his later actions, there's no reason to believe that he would care about putting his daughter in danger.
* ''Film/TheConspirator'': Aiken mistakenly asks a question at trial without knowing the answer. It was dumb luck that it worked in his favor, and he confesses this to his friends.
* ''Film/TheWolverine'': After Logan finishes interrogating Noburo Mori, Minister of Justice, he throws him over the balcony of his penthouse, to have him land in the pool below. This is of course taken straight from the above-mentioned ''Film/DiamondsAreForever''.
-->'''Yukio:''' How did you know there was a pool down there?\\
'''Logan:''' I didn't.
* ''Film/WorldWarZ'': [[spoiler:Gerry uses this line after one of the WHO Doctors asks him how he knew that injecting himself with a virus to camouflage him from the zombies.]]
* ''Film/TerminatorGenisys'': Sarah Connor encounters a T-1000 disguised as Kyle Reese at about the same time the actual one comes in. After a short standoff, she shoots one in the foot and it's the T-1000. Kyle is not amused when Sarah admits that she wasn't totally sure and so went for a non-fatal wound.

* ''Film/Alien3'': A bit before the climax, Dillon off-handedly asks about Ripley having slept with Dr. Clemens in a way that implies he already knew. When she replies that he's obviously been a peeping tom, he says that he wasn't, but her response did confirm his suspicions.
* {{Inverted|Trope}} in ''Film/VanHelsing''. After Anna stops Van Helsing from shooting her brother-turned-werewolf, he shouts, "He's not your brother anymore!" She asks if he knew before or after she stopped him -- thinking he would not have shot if he didn't realize it -- and he answers that he knew before she stopped him.
* A variant occurs in ''Film/Ronin1998'': Sam, the experienced mercenary, thinks that one of the younger upstarts on the job is only pretending to be a former SAS commando, and starts asking more and more pointed questions about life as an SAS operative. Finally, he demands to know the color of the boathouse at Hereford (where the SAS is headquartered) and the guy can't answer... because he doesn't know. He leaves in disgrace. Then:
-->'''Vincent:''' What color ''is'' the boat house at Hereford?\\
'''Sam:''' How the fuck should I know? I've never been there.
* In ''Film/RogueOne'', during an intense battle, Jyn reflexively shoots and destroys an Imperial droid identical to K2-SO. Jyn makes an OhCrap face... only to spot the real K2-SO standing right behind the fallen droid:
-->'''K-2SO:''' Did you know that wasn't me?\\
'''Jyn:''' [[BlatantLies Oh...]] [[IMeantToDoThat of course!]]

* Happens in ''Literature/TheScienceOfDiscworld'' when the Dean sticks his hand into the nascent Roundworld project:
-->"That was a really very foolish thing you just did," said Ridcully. "How did you know that it wasn't dangerous?"\\
"I didn't," said the Dean cheerfully. "It feels... cool. And rather chilly. Prickly, in a funny sort of way."
* In ''Literature/TheDayOfTheJackal'', when asked how Lebel knew which minister was being spied on by a mole, he answered he didn't know...so he tapped ''all the ministers' phones.''

* ''Series/RobinOfSherwood'' in "The Sheriff of Nottingham", the new Sheriff of Nottingham captures Robin Hood and all the outlaws, except for Nasir, who had gone to have a duel to the death with Sarak, the new Sheriff's saracen servant who Nasir had some unfinished business with from way before the show began. (Sarak, conveniently, usually wore clothes that hid his face.) The outlaws are about to be executed when a figure wearing Sarak's clothes walks in. The Sheriff offers Robin and the outlaws a chance to go free if he manages to kill Sarak. Robin takes the crossbow but hesitates to take action, while the Sheriff urges Sarak to kill Robin. "Sarak" then throws a sword into the Sheriff's stomach and takes the veil off his face, revealing himself as Nasir. Later on...
-->'''Marion:''' How did you know? That it was Nasir and not Sarak?\\
'''Robin:''' I didn't. I just live in hope.\\
'''Marion:''' You...!

Can be disturbing when you realized that our hero had no problem killing someone and just happened to kill someone evil. Alternatively, sometimes the hero might have known the truth all along and just be yanking the chain of the person asking the question.

* In ''Fanfic/HuntersOfJustice'', [[WebAnimation/{{RWBY}] Team RWBY, Qrow]], and [[ComicBook/TheLegionOfSuperHeroes Saturn Girl]] are working with ComicBook/JonahHex to stop a train robbery being pulled by the time traveling thief Chronos. While riding on horseback among Chronos' {{Mooks}}, Ruby can't take the shot because she doesn't want to kill people if it can be avoided. Jonah wastes no time and shoots a mook in the head. The spray of oil reveals that they're MechaMooks dressed in period clothing. Being mindless drones, the heroes have no reservations in tearing them apart. When Qrow asks if Hex knew they weren't living people, the CombatPragmatist simply says he didn't.

* During a Franchise/SherlockHolmes parody in ''Webcomic/TheWhiteboard'', Moriarty assumes that Holmes is accusing him of ordering the murder of Blone. Instead, Holmes implicates him in the prior death of Blone's assistant, [[IncrediblyLamePun Apartington]].

** In ''Battle Tendency'', Joseph reveals in his [[InnerMonologue inner thoughts]] that his final trump card against Kars was nothing more than him just getting lucky, but the fact that he thought otherwise [[VillainousBreakdown is more than enough to drive him crazy]].

* In ''Film/RogueOne'', during an intense battle, Jyn reflexively shoots and destroys an Imperial droid identical to K2-SO. Jyn makes an OhCrap face... only for the real K2-SO to walk in and notice the fallen droid:

* Implied in the ''Series/BabylonFive'' episode "Spider in the Web":

* In the ''Series/Daredevil2015'' episode "In the Blood", Karen Page goes to an auction where Union Allied assets are being auctioned off. While she's there, Ben Urich sits down behind her and tells her to avoid looking suspicious by bidding on some of the smaller lots. When they reconvene at the diner that they'd had a meeting at earlier in the day, Karen asks Ben how he knew she was there, and Ben replies, "I wasn't looking for you."

* ''Series/RedDwarf'': In "Can of Worms", Lister, Rimmer, and Kryten are hunting shape-shifters when they are approached by the Cat. Lister (who is temporarily emotionless) blows him away without a second thought, revealing him to be a polymorph. Rimmer asks how he knew he wasn't the Cat, and Lister calmly replies "I didn't." It should be noted that unlike other examples this was a deliberate act. Lister had his emotions drained to make him immune to the polymorphs so he literally didn't care who he shot.

* ''Series/StarTrekDeepSpaceNine''. When Worf realizes General Martok is suffering from post-traumatic stress disorder as a result of his imprisonment, he [[ChallengingTheChief challenges Martok's leadership in the Klingon tradition]], then lets him win the subsequent knife fight. Reinvigorated, Martok rallies to his command and saves the day. Later, knowing that Worf lowered his guard deliberately, Martok asks how Worf knew he wouldn't kill him. Worf replies simply, "I didn't". Realizing that Worf was literally willing to die to bring Martok out of his slump, the general is so impressed that he officially adopts Worf as a member of his House.
* In the ''Series/{{Supernatural}}'' episode "Taxi Driver", Sam's attempt to break Bobby out of Hell is interrupted by a duplicate Sam trying to pass himself off as the real one in the confusion. After Bobby kills the false Sam, Sam asks if Bobby knew it was the fake, and Bobby admits that he had to guess.

* On ''Manga/YuYuHakusho'' Yusuke is faced with a SpotTheImposter predicament and is told he has to punch the culprit as hard as he can to expose him. He correctly chooses Kuwabara but only did so because he knows Kuwabara is used to being hit by him while ruling out the others. He did mention before doing so that he hoped he was right.

* In ''VideoGame/BaldursGateII'' you could run into a small lair of mind flayer beneath the city of Athkatla, hiding in a secret room in the sewers. To open the door you require to keep in your inventory a key that is dropped in a distant unrelated place, with only a vague description about having an odor like that of the sewers and no hint about where to find its lock. After you clear the lair, you discover a note whose description states that it is written in an alien language that you can't read, but likely the mind flayers where up to some conspiracy, and your mere presence there surely disrupted their plans whatever they are.

-->'''Moriarty:''' ...How did you know about that?!?
'''Holmes:''' I didn't. I only ''suspected'', until now.\\