History Main / NowYouTellMe

* A rather non-comedic use of this trope (or perhaps a BlackComedy use) shows up in ''Manga/RanmaOneHalf''. [[SinkOrSwimMentor Genma Saotome]] doesn't read the next page of the training manual detailing the [[HarmfulToMinors Neko-ken]], which says that the technique is [[UselessUsefulSpell impressive sounding, but non-functional]], until after he's already trained his six-year-old son Ranma in it. Oh, and it isn't just useless, it causes [[HarmfulToMinors permanent mental damage]] to the trainee, afflicting them with a permanent and deeply rooted [[WhyDidItHaveToBeSNakes phobia of cats]].

* Ryuk of ''Manga/DeathNote'' does this repeatedly with Light when he uses the Death Note.
-->'''Light:''' He waits until ''now'' to mention that detail? Damn Shinigami!

* ''Literature/{{Slayers}}'' uses this when the gang is hunting through a dungeon of some sort. Lina is reading warnings out of a book, and Gourry keeps picking up on the first half of the warning instead of the whole. The first warning is something like "Pressing the button... is something you should not do." For the second, Gourry doesn't press the button, but the warning is something like "Don't walk past without pressing the button."
* Happens in ''Literature/RestaurantToAnotherWorld'' when [[OurDwarvesAreAllTheSame Guildheim brings Garde]] over to the eponymous [[InnBetweenTheWorlds Nekoya]] one Saturday to have Fried Seafood Platters, Guildheim casually mentions that the seafood tastes much better when dipped in Tartar Sauce: immediately after Garde had just finished his own Platter.
* Happens a lot in ''VisualNovel/BlessingOfTheCampanella''. Salsa will do something, and Ritos will tell her about a certain hazard too late for her to avoid it. Salsa shouts the trope name, which then brings GravityIsAHarshMistress into things.

* Happens in Kaiba's and Joey's first Duel in ''Anime/YuGiOh'' when Joey attacks with his monster which has a higher attack power than Kaiba's.
--> '''Yugi:''' Wait! The Battle Ox is resistant to all Fire Type attacks!\\
''[Flame Swordsman is defeated]''\\
'''Joey:''' ''Now'' he tells me...

* In ''Anime/APlaceFurtherThanTheUniverse'', Kimari, Shirase and Hinata head to Shinjuku, where some members of the civilian expedition to Antarctica will be meeting up, and plan on seducing one of the male members to get a spot on the trip. After Kimari fails miserably, Shirase vehemently refuses to try, but Hinata and Kimari shove her out of their hiding place, in front of the expedition members. Too late, they realize why Shirase refused- since she was the daughter of an expedition member who went missing (which is why she's so determined to go to Antarctica), and had tried to get into the expedition before, the expedition members recognize her.
* The English version of episode 31 in ''Anime/KirbyRightBackAtYa'' has Tiff say this word-for-word after Meta Knight mentions how destructive Mike Kirby's singing is....after Kirby's destructive singing levelled Dedede's own castle.

* ''WesternAnimation/TreasurePlanet'': Shortly after Jim finds and restores B.E.N.'s memory, the latter remembers that [[spoiler:Captain Flint [[EarthShatteringKaboom rigged Treasure Planet to explode]] if anyone found his treasure. Of course, given that the trap was sprung the second the characters entered the treasure chamber in the planet's core, this trope was the only possible outcome]].

--> '''Izaya:''' Oh, and here's one little bit of advice for ya. Whatever you do, don't talk to Shizu-chan about his younger brother.
--> '''Shuuji:''' ''[thinking]'' Wish you'd told me that six months ago.

-->'''Scrooge:''' You mean you never took flying lessons?!
-->'''Launchpad:''' Well, I took a [[ObligatoryJoke crash course]]
-->'''Scrooge:''' ''(facepalms)'' [[ThisExplainsSoMuch Now he tells me]].

-->'''Jiminy:''' Quick, Pinoke! The kids! The boys! They're all donkeys--''OH! YOU, TOO!''
-->''(Pinocchio nods in a frightened yet confirming way)''
-->'''Jiminy:''' Come on, quick! Before you get any worse!

* ''WesternAnimation/BatmanBeyond'', when Terry is fighting [[{{Berserker}} Mad Stan]]:

* In ''WesternAnimation/{{Futurama}}'', Fry is sent to deliver a package to the Emperor of a desert planet. He drinks from the first bottle he sees when he arrives in the throne room, which turns out to be their emperor (the aliens are liquids). Thus, according to the culture's laws, he is [[KlingonPromotion appointed the new Emperor for having killed the previous one]]. The package he originally came to deliver is now ''for him'' so he opens it and finds a sign reading "don't drink the emperor", [[CantYouReadTheSign which he hangs next to dozens of the same sign in various alien languages]].

** In one episode, Dr. Doofenshmirtz yells this when he uses the ejector seat on a robotic dragon vehicle and its computer tells him that [[MyopicArchitecture it doesn't come with a parachute]].
** In another episode, Candace has the boys build one of their inventions to find out where it disappears to whenever she tries to bust them. At the end of the episode, she says this after Ferb tells her [[ItMakesSenseInContext even doing nothing can have an effect]].

* ''WesternAnimation/SouthPark'': In the first HalloweenEpisode, the town is plagued by zombies created as a result of Worcester sauce accidentally being used as embalming fluid at the morgue. Stan calls the company's help line and the man on the other end says "The first thing, and this is ''very'' important, is not to go killing zombies left and right". Stan looks up and sees Kyle and Cartman doing exactly that, and simply says "...Okay..."

* ''WesternAnimation/TheLoudHouse'': In "Dream a Lily Dream", Lincoln says this almost word for word when Lisa tells him and the other Loud siblings at the last second that they could get trapped in Lily's dream forever if Lily wakes up too soon. And again when Lisa explains, while they are already in the dream, that [[NeverSayDie if anyone gets taken out in the nightmare, they're taken out in real life]].

* In ''[[WesternAnimation/BatmanTheAnimatedSeries The New Batman Adventures]]'' episode "Joker's Millions", Harley delivers this great line:

--->'''Shadi:''' Jak się masz? My name is Shadi. I am here to warn you gypsies that if you disobey your crazy papa and reject your duty as tomb-keepers, something really ''bad'' will happen.
--->'''Ishizu:''' But we already did that! What good is warning us going to do now?
--->'''Shadi:''' ...I am a ghost.
--->'''Ishizu:''' Yes, but that still doesn't explain-
--->'''Shadi:''' High five!

-->'''Robber:''' You used too much, Mugsy.
-->'''Sylvester:''' Now he tells him.

* ''WebAnimation/{{RWBY}}'': In Volume 6, the heroes are on a train to their next destination when it is attacked by the Creatures of Grimm. While trying to figure out how to save the passengers, Oz reveals that the Relic of Knowledge their carrying draws Grimm to it, [[WhatTheHellHero infuriating the others.]] This would be the catalyst to a series of events that reveal that their ultimate enemy Salem has CompleteImmortality...and that Oz (By his own admission) never had a plan to defeat her. Needless to say, Team RWBY are outraged to learn this.

::: Of course, you learn this ''after'' [[spoiler:Shepherd and his men have shot Roach/you and Ghost, and are busy dousing you in gasoline and setting you on fire.]]

* ''Film/BackToTheFuture1'': Marty is blown across the room when he tries to hook up to the giant amplifier in Doc's garage. Then the Doc calls and warns Marty not to do that because there's a slight chance it'll overload.

* In ''Film/ParanormalActivity'', Micah uses this against Katie in their final fight that she hasn't told him that [[spoiler:she has been followed by a demon for most of her life.]]
* ''Film/WeWereSoldiers'': [[ColonelBadass Moore]] puts out a call to his helicopter crews that the LZ is hot. Crandall, the lead pilot, receives the message at roughly the same time that bullets start pinging off his Huey's airframe.

** In ''Film/{{Doctor Strange|2016}}'' after getting the villains hoisted by their own petard Strange repeats a line he said earlier when caught trying a spell from a restricted tome.
--->'''Stephen Strange:''' They really should put the warnings before the spell.

--->'''Iron Man:''' Cap, you've got {{incoming}}!\\

** ''Film/GuardiansOfTheGalaxyVol2'': Drax shouts "Mantis, look out!" almost ten seconds ''[[DelayedReaction after]]'' Mantis gets bashed into unconsciousness by a piece of flaming debris.

* In ''Film/AViewToAKill'', James Bond uses Stacey's shotgun to dispatch some mooks, who then get up right after. When Bond asks Stacey what the shotgun was loaded with, she responds with "Rock Salt". Cue Bond saying the trope word for word.

* ''VideoGame/TheJoyOfCreationReborn'' has a gaming equivalent; you need to flash Ignited Freddy with your flashlight 10 times to complete the Office level... which isn't directly told until ''after'' you lose by way of Freddy entering your room in complete darkness.

** Used when Goku asks Old Kai how long Potara fusion lasts for, the latter says it's permanent. ''After'' Supreme Kai and Kibito have already demonstrated it. Luckily, ''Anime/DragonBallSuper'' reveals that the Dragon Balls can reverse it (and that it's only permanent if one of the people involved is a Kai).

* In ''WesternAnimation/DuckTalesTheMovieTreasureOfTheLostLamp'', Scrooge asks Launchpad, "You mean you never took flying lessons?" [[CaptainCrash Launchpad]] says, "Well, I took a [[ObligatoryJoke crash course]]." Scrooge, [[FacePalm facepalming]], says, "[[ThisExplainsSoMuch Now he tells me]]."

* ''Anime/{{Pokemon}}'':
** In the episode "[[Recap/PokemonS5E22DuesAndDonts Dues and Don'ts]]", Ash checks Delibird in the Pokedex. It says Delibird has a attack called Present. Delibird gives Ash and friends glowing ball "presents", which a couple seconds later go off as bombs. Dexter adds that some of Delibird's Presents explode. Ash says "now you tell me".

* ''Film/BackToTheFuture'': Marty is blown across the room when he tries to hook up to the giant amplifier in Doc's garage. Then the Doc calls and warns Marty not to do that because there's a slight chance it'll overload.

* During the shooting of ''Film/TheEmpireStrikesBack'', this was practically director Irv Kirschner's CatchPhrase whenever one of the special effects failed spectacularly. R2-D2 is skidding all over the place? We didn't test to see if it could run on the artificial snow of the Echo Base set. [[EpicFail One of the X-Wing's wings snapping off while Yoda is lifting it from the swamp]], in full view of a horrified Creator/GeorgeLucas? We forgot to test if the model could withstand being underwater. "Now you tell me!" Irv would snap.

* PlayedForDrama in ''WebAnimation/{{RWBY}}'': In Volume 6's opening, the heroes are taking a train on their way to secure the Relic of Knowledge in Atlas. Along the way, they are attacked by the Creatures of Grimm, where Oz reveals that the Relic attracts Grimm. Needless to say, [[WhatTheHellHero no one takes this well,]] and the fallout sets off a chain of events that reveals Salem, the BigBad [[spoiler: has CompleteImmortality, something Oz has known and kept hidden for ages. What he ''doesn't'' know is how to defeat her, but has acting like he does to secure his leadership.]]

* From ''Paul Merton: The Series'' -
--> For 3 days and 3 nights we marched over open country, marching over mountains, marching under streams, from the Arctic Circle to the Sahara desert. We marched and marched and marched, until at last it was time to open our SealedOrders.
--> *reads* "Don't march anywhere."

* Happens in ''Literature/RestaurantToAnotherWorld'' when Guildheim brings Garde over to the eponymous [[InnBetweenTheWorlds Nekoya]] one Saturday to have Fried Seafood Platters, Guildheim casually mentions that the seafood tastes much better when dipped in Tartar Sauce: immediately after Garde just finished his own Platter.

* In ''LightNovel/{{Durarara}}'', a man named Shuuji Niekawa approached [[TheBerserker Shizuo Heiwajima]] and [[BerserkButton makes the mistake of mentioning Shizuo's younger brother, Kasuka/Yuuhei Hanejima]], which results in him being tossed into the sky. Shuuji later visits Izaya Orihara, asking for info about the toughest person in Ikebukuro, namely Shizuo. Being that [[ArchEnemy Shizuo's not one of Izaya's favorite people]], he gives the man information about a friend of his, [[HeadlessHorseman Celty Sturluson]], instead. Before Mr. Niekawa leaves, Izaya gives him a rather late warning.

* ''LightNovel/{{Slayers}}'' uses this when the gang is hunting through a dungeon of some sort. Lina is reading warnings out of a book, and Gourry keeps picking up on the first half of the warning instead of the whole. The first warning is something like "Pressing the button... is something you should not do." For the second, Gourry doesn't press the button, but the warning is something like "Don't walk past without pressing the button."

In a ''ComicStrip/{{Cathy}}'' comic, a male friend brings his baby over to Cathy's place, confident that she would not try to ran her ideas about child rearing down his (and the kid's) throat, as everyone else had been doing. He does have one request -- not to let the baby have any sweets, since they're raising her in a 100% sugar-free environment. He said this just after Cathy had set the baby down next to a [[OhCrap bowl of leftover Halloween candy]].