Exact Eavesdropping

""In books and vids, those being eavesdropped upon always thoughtfully explain what they are talking about for the edification of the eavesdropper. The eavesdroppee says, 'Of course, as you all know, the cab to which I refer is Sherlock Holmes's hansom cab which had been accidentally driven off a bridge during a heavy fog while following the Hound of the Baskervilles, and which I found it necessary to steal for the following reasons.'""

- Connie Willis, To Say Nothing of the Dog

If a character in almost any type of fiction gets a chance to eavesdrop, they will almost certainly hear something important. So, for instance, if our hero finds himself hiding in the villain's base listening to a conversation, chances are it's going to be about the villain's latest plans for world domination, rather than two random Mooks talking about their weekend plans. It's also very likely that the villain will take this opportunity to go over important information everyone they're talking to should already know, in order to give the hero all the context and backstory he needs. In this way, this trope can function as a sort of in-story version of As You Know, only instead of filling in backstory for the audience, it's being done for the character, and is a way to get vital, plot-moving information from one group or person to another.

In less serious circumstances, it can also be a way for a one character to learn what someone else thinks of them. So whenever Alice is unseen but can hear Bob talking, chances are Bob will say something important about Alice. There will also be occasions where the person Bob is talking to about Alice knows full well that Alice is listening and will often be asked to talk to Bob specifically for this sort of information.

This applies even if the talking character would not normally be coherent. Characters who talk in their sleep in the grip of Bad Dreams often give remarkable clues to the trauma causing the dream.

Since this trope is Older Than Steam, subversions appear frequently. Two of the most common are: first, to have a character think they've overheard one thing, when in fact they missed an important detail that changes the situation entirely. This can lead to Innocent Innuendo and/or Three Is Company situations. The second subversion is to have a character who is aware of this trope annoyed when it completely fails to happen. Despite this, it's still played straight often enough to be an Undead Horse Trope.

The trope mostly exists because Realistic Diction Is Unrealistic.

See also: Contrived Coincidence, and Conveniently Coherent Thoughts for a mind-reading variation. Contrast The Omniscient Council of Vagueness. Characters who are likely to benefit from this trope include the Snooping Little Kid and Amateur Sleuth. If the eavesdropper gets caught, the question is How Much Did You Hear? Occurs frequently when you use Curtain Camouflage.

Anime and Manga
"I know about that."
 * In Mahou Sensei Negima, Cute Ghost Girl Sayo floated in just as the Elaborate University High teachers were informing Negi and his small group of True Companions of everything they'd already just discussed. This worked well in favor of School Newspaper Newshound Kazumi Asakura.
 * This is fairly well-justified; Asakura was cognizant of the fact that something fishy was going on, since she had wanted to head to the World Tree Plaza, but her desire mysteriously flipped around. She forced herself to get closer, and, upon seeing a bunch of the teachers grouped together and the plaza oddly empty, accepted Sayo's offer to help. Given the circumstances, she was more or less guaranteed to overhear something significant.
 * It's also sometimes subverted (though better examples exist in his previous work, Love Hina). Take the second manga's whole "Negi is a prince" fiasco.
 * Another instance was when Nodoka overheard Negi and Asuna's talk about activating Pactio cards.
 * Duck in Princess Tutu hides behind a fountain and hears what Mytho truly thinks of Tutu. Justified in that Fakir, with whom Mytho was speaking, knew she was there and purposely brought up the subject.
 * Used (straight) a couple of times in Nanaka 6/17, with plot significance.
 * Hayate the Combat Butler uses this for humor.
 * The first time, Hayate, Wataru and Nagi are spying on Saki (Wataru's Meido) and Kaoru's marriage meeting. They can't hear what's being said, so Hayate reveals that he knows how to read lips, and provides 'long-range' version of this trope for the younger two. This being for humor, he reads it completely wrong. Afterwords, Wataru has interrupted the meeting and Nagi asks Hayate how confident he is in his skills, he replies that he's fairly confident.
 * In the last episode of the second season, Maria does similar to the above, with significantly better results. This one is only in the anime though.
 * There's also a scene in which Nagi hides Isumi in, what is functionally a closet, and gets Wataru to admit his feelings for Isumi. Unfortunately she comes out of hiding before he leaves and he furiously backpedals, killing any chance of the confession having any effect.
 * There's also a scene during the Athens arc where it's implied that Yukiji knows that Karou is listening and gives Hinagiku love advice to give up her chase (in Hinagiku's case it's of Hayate), it's possible she's trying to get her fellow teacher to give up on her as well.
 * Kazumi Magica has Mirai Wakaba during the combat between Kazumi and Satomi.
 * Somehow inverted in chapter 26 of the manga Saga of Tanya the Evil, which is perhaps to be expected of a series that's entertainment value is mostly derived from misunderstandings. The United Kingdom was confident that the Empire knew everything about their highly classified plan, based on the actions of the 203rd mage wing. During the operation in question United Kingdom hacked into Visha's Operation Orb. They stole an audio recording that was from part of an unimportant conversation.


 * They took that quote as not only a confirmation that the enemy (well, the UK is technically "neutral" with the Empire, but they UK and the Empire aren't on good terms) knew what they were up to, but left that message to taunt them if the UK managed to hack into the operation orb.

Comic Books

 * In The League of Extraordinary Gentlemen Vol. 1, the eponymous League is being employed by the mysterious Mr. M. Eventually, he then explains his entire backstory to a character that already knows it, allowing the eavesdropper and the audience to gain vital information.
 * This is almost-instantly subverted when
 * This is one of those tropes that Disney Mouse and Duck Comics play completely straight again and again in spite of how silly it is.

Fairy Tales

 * In The Grateful Beasts, the blinded and crippled Ferko happens to rest under a gallows, where he happens to hear two ravens discussing magical cures in the vicinity.
 * In "The Raven", doves land on the ship's mast and talk about the perils the hero's brother will face.
 * In "True and Untrue", True hears of magical cures from a wolf, a fox, and a bear.
 * In "Faithful John", Faithful John hears of the peril the king and his bride are in from ravens who happen to be talking of it and the magical Curse that will fall on anyone who says it.
 * In "Parsley", the ogress explains to her neighbor how Parsley can't escape owing to a spell she cast, and Parsley hears it and how to break it.

Film -- Animation

 * In the first Shrek film Shrek is about to confess his love to Fiona, when he overhears Fiona talking to Donkey, saying that no-one could love a monster like an ogre. Of course, he is unaware that she is talking about the curse that turns her into an ogre, which she conveniently doesn't explicitly mention again until just after Shrek gets disgusted and leaves.

Film -- Live Action

 * Star Wars: Attack of the Clones, when Obi-Wan is sneaking through the Geonosian caverns and happens upon Count Dooku and the Separatists, who are in the middle of a conversation which tells him everything he needs to know.
 * Averted in the next movie, when Obi-Wan again sneaks around but happens upon the separatists just too late to hear Grievous telling the others where they will be hiding next. Of course, this time it's important for the plot that he doesn't get to know it yet.
 * Goldfinger is a notorious example, with the title character being overheard by Bond revealing all the details of his plan to a group of people he murders 30 seconds after leaving the room.
 * In the original book, he only killed the people who didn't agree to help with his scheme, making that scene more plausible.
 * Subverted in The Big Lebowski. The Dude is in a conversation with Jackie Treehorn when the latter receives a call, writes down something on a notepad, tears off the notepad, and excuses himself. The Dude, in full sneaky investigator mode, grabs the notepad and shades it with the side of a pencil to highlight the impression made on the next sheet of paper. It turns out to be
 * Friends With Benefits has Jamie managing to listen in when Dylan is repudiating her as a potential girlfriend to his sister.
 * The Rocketeer has movie star Neville Sinclair hearing Cliff Secord tell his actress girlfriend Jenny Blake about the rocketpack Sinclair is looking for.
 * White Christmas has a classic subversion of the first type, when Emma is distracted at a crucial moment while listening in on a telephone call and completely misunderstands Bob and Phil's plans to honor the General.

Literature
"Wiretapping cannot be employed indiscriminately, but its effectiveness is illustrated by this transcript of a conversation between two gang bosses in the New York area whose phones had been tapped by the F.B.I. Anthony: Hello? Rico? Rico: Hello? Anthony: Rico? Rico: Hello. Anthony: Rico? Rico: I can't hear you. Anthony: Is that you, Rico? I can't hear you. Rico: Hello? Anthony: Operator, we have a bad connection. Operator: Hang up and dial again, sir. Rico: Hello? Because of this evidence, Anthony (The Fish) Rotunno and Rico Panzini were convicted and are currently serving fifteen years in Sing Sing for illegal possession of Bensonhurst."
 * In Connie Willis' novel To Say Nothing of the Dog, the main character finds himself eavesdropping on a few occasions, and frustrated because no one gives enough context to be useful. He even references this trope, as the page quote shows.
 * The second Book of Amber series subverts and lampshades this - when Merlin's Aloof Big Brother and the corrupt clergyman talk as they walk through the hall, Merlin only hears a snippet of the conversation and is annoyed that This Is Reality.
 * In Rudyard Kipling's The Second Jungle Book story "Letting In the Jungle", after being thrown out of the human village Mowgli overhears the village hunter Buldeo telling some other men that the couple who had adopted Mowgli are due to be executed. Armed with this knowledge Mowgli sets out to rescue them.
 * In Nicholas Nickleby by Charles Dickens, the author scornfully comments on how, in the theatrical productions of the traveling players, the comic relief character always happens to overhear the villains' plans and tell the hero. Then in a later chapter, Newman Noggs, the comic relief character of the story itself, happens to overhear the villains' plans and runs to tell Nicholas.
 * Played very straight in CS Lewis' The Horse and His Boy. While Aravis and Shasta are separated, they both manage to overhear important, secret pieces of information—in her case, a plan to invade the country of Archenland, and in his, the shortcut through the desert that will allow them to get there ahead of the invaders.
 * This happens right in the beginning, too, when Shasta overhears Arsheesh and the Tarkaan haggling over him.
 * Shasta habitually eavesdropped on Arsheesh though, which ups his odds.
 * Happens all the time in David Eddings's books. Almost each time the heroes arrive in a new place, they will come across a pair of enemy mooks telling each other everything that is to be known about it (and, typically, calling each other by name in their very first lines).
 * Occasionally subverted, such as very early in the Belgariad, when Garion hears Mister Wolf and Aunt Pol (later revealed to be ) that makes no sense to either him or the reader, but makes perfect sense to Wolf and Pol, and the reader if they read the series again.
 * Or, you know, read the prologue.
 * In the novel Ayla and the Networks of the Whateley Universe, the Whitman Literary Girls magically eavesdrop on She-Beast and Nephandus, and hear just what they're looking for.
 * Extra funny because the WLG are explicitly Author Avatars.
 * This happens again later on, with a different group, the Good Ol' Boyz, come into possession of a tape that seems to implicate Ayla and She-Beast in a plot to kill some poor old lady's children and feed them to her.
 * Played straight and responsible for most of the suspense in the period piece A Murder For Her Majesty. The main character witnesses the murder of her father and overhears a conversation by the killers, which is what kickstarts the plot. She overhears two conversations later on by the killers and co-conspirators. She herself, disguised as a boy, is discovered for who she is by accidentally saying things out loud that the bad guys overhear when near her. A lot of convenient overhearing, but what the heck, it makes the story fun.
 * This is how Jim finds out that Silver is a pirate in Treasure Island.
 * Subverted in Forward The Foundation by Isaac Asimov: Hari Seldon's grandaughter Wanda genuinely overhears (perhaps telepathically) members of the Psychohistory Project plotting against Professor Seldon, but, being a little girl, she doesn't understand their complicated words. It never becomes clear whether the term is "lemonade", "layman-aided", or "Elar-Monay" (the names of the conspirators).
 * Played extremely straight in Ozma of Oz, the third Land of Oz book. The Nome King has transformed people into decorations for his palace, and challenged the main characters to guess which ones they are. This was a needle-in-a-haystack game until Billina the Hen overheard the Nome King and his servant going over all the information she needed to know, and it's very much an As You Know conversation.
 * The first subversion occurs in the first Harry Potter book. Harry overhears what seems to be Snape forcing Quirrell to help him steal the Stone. It turns out
 * Subverted and played straight in book five.
 * Played straight when Dudley comments about Harry sleep talking while reliving Cedric's murder.
 * Played straight in the sixth film when  breaks up with Ron for mumbling   name while semi-unconscious.
 * There is also a Double Subversion in book four.
 * And in the seventh book, while wandering around with no idea what to do next, the trio happen upon some other refugees who mention the Sword of Gryffindor, cluing them into its significance. Later, the portrait of Phineas Nigellus overhears Hermiony telling Harry that they're in the forest of Dean, allowing him to tell.
 * The sleeptalk version is played straight in the first book of The Wheel of Time: Rand's father Tam has a high fever and unconsciously reveals to Rand that he is not his real father.
 * Subverted in Dr. Hyde, Detective, and the White Pillars Murder: The detectives overhear several conversations, but learn nothing.
 * Subverted in A Song of Ice and Fire. In A Game of Thrones, Arya overhears a conversation between conspirators, but the conversation involves the political situation on a different continent, they don't drop many particular details, and speak metaphorically for a large chunk of the conversation. Since Arya's only ten, not only does she misunderstand, she forgets large parts of the conversation (and also misidentifies the dragon skulls being stored in the room she's hiding in as "monsters" when asked.) As a result, when she tries to relate the conversation to someone else, it's garbled to the point of incoherency.
 * Subverted before that, when overhears a pair of political conspirators, who turn out to be . They catch, and  immediately retaliates by throwing  off a tower.
 * Generally averted or subverted in ASOIAF; characters will only get partial information, or the true meaning of the conversation will be obscured by the conversation, or the information will only be relevent to a completely different plotline. Brienne, for instance, tends to hear all kinds of interesting information about other characters and events in her travels, but she dismisses most of it as it's entirely irrelevent to her own quest.
 * Justified in The Dresden Files - Harry uses Listening with a capital L to eavesdrop.
 * Parodied by Woody Allen in "A Look at Organized Crime"


 * In Robert E. Howard's "Jewels of Gwahlur", Conan the Barbarian set out after overhearing things.
 * Queen Etheldredda in Septimus Heap does this to verify everything she hears, to the point that she doesn't trust anything that she hasn't eavesdropped upon.
 * Subverted in one children's novel, in which the main character thinks she overheard a murder plot, but realizes the people were talking about writing a book.

Live Action TV

 * Parodied in an episode of Family Matters. Steve Urkel eavesdrops on Laura from the hotel room directly above hers, immediately hearing a seductive male voice that he believes to be Laura's date in her room. A couple seconds later, the voice proceeds to talk about dog food—Laura was watching TV by herself, and the voice was from a dog food commercial playing on the TV.
 * In 24, they keep hearing of and eavesdropping about imminent attacks, but the characters are extremely unlucky in that the eavesdroppees tend to use terms like "The Target" instead of actually giving useful information.
 * In The Comic Strip Presents' Enid Blyton parody "Five Go Mad in Dorset", the Famous Five overhear two villains conspiring: "Blah Blah Blah kidnapped scientist blah blah. Blah blah Kneecap Hill blah blah. Blah blah atom bomb blah." That's right - the villains actually say "Blah blah".
 * Partly subverted in an episode of Young Indiana Jones, in which Indy, while fighting in Europe during WWI, is told to spy on the Germans. When he gets to their base in the middle of the night, he falls asleep listening to the German soldiers talk about the most mundane topics, and barely wakes up in time to hear them discuss their acquisition of two howitzer guns.
 * In Battlestar Galactica Reimagined, when Callie follows someone and listens in on a conversation, she hears exactly what she wanted to hear despite the characters not having a need to say it again.
 * In Robin Hood Marian was always in the right place, at the right time, to hear exactly what the Sheriff and Guy of Gisborne were planning, and pass it on to Robin. The villains would often discuss their plans right in front of her and then wonder how Robin was always one step in front of them.
 * Although it happens in nearly every Kid Com and Teen Drama, whenever a Saved by the Bell character listens in on a conversation, it always relates or leads to relation problems.
 * In an episode of Gilligan's Island, two Soviet cosmonauts land on the island after missing their target. Gilligan later overhears the two of them plotting to get the castaways drunk at a party and tie them up so they can't return to civilization and embarrass the Soviet space program by telling the world that they missed their target. One wonders why the two Russians would be privately conversing with each other in English.
 * This trope is parodied in an episode of Blackadder III. Baldrick overhears two actors discussing how they intend to murder the Prince in a hilariously gory fashion, and immediately suspects a plot. In fact, the actors were merely rehearsing a play.
 * Parodied in one of The Colbert Report's Tek Jansen stories. The hero is hiding in a kitchen when the bad guys enter and explain their evil plan out loud. They then leave the kitchen, having entered it for no other reason.

Tabletop Game

 * Gleefully averted in a lot of Forgotten Realms materials, as Ed Greenwood loves Gambit Pileups and has much fun with teasing fragments that make great plot hooks and even better Red Herring. There were conversations in Elminster at the Magefair short story (where the wizard community is portrayed as bordering on madhouse), but the pinnacle of this concept is phenomenon of "Weave Whispers" (the original article died in site overhaul, but you can see some here) - random "snippets of voices or sounds, usually from long ago (and therefore persons or creatures long-lost), that can be heard in certain places, at certain times", presumably caught and preserved by side effects of interacting spells - each fragment self-contained without any way to pry more out of it.

Theatre

 * William Shakespeare plays with it a couple of times:
 * In Hamlet: First Hamlet, eavesdropping on Claudius, decides not to kill him, since it sounds like he's praying. Actually, Hamlet had just missed the important part, and Claudius was really lamenting the fact that he couldn't pray, because of all the murdering and usurping he'd been doing lately. Then Polonius tries to set up this trope, hoping to learn something by eavesdropping on Hamlet talking to his mother. Instead, he gets stabbed, which isn't particularly helpful.
 * Another Shakespearean instance, which proves pivotal to the plot—the eavesdropping scene in Othello. Horribly subverted as Othello completely misunderstands and misinterprets what Cassio is saying (it doesn't help the courtesan he's seeing chucks Desdemona's hanky back in his face either).
 * Shakespeare even invokes this trope twice in Much Ado About Nothing:
 * The supporting characters conspire to have Beatrix and Benedick overhear them talking about how each is crazy in love with the other in order to get the two to fall in love. It works, sort of.
 * And in the same play, the villains conspire to have Claudio overhear a conversation he misinterprets, which is basically the entire plot.
 * Given that the "Nothing" in the title was pronounced "Noting" in Shakespeare's day, the title hangs a lampshade on it.

Video Game

 * This is a game mechanic in Assassin's Creed. One of your submissions in each assassination is to seek out very specific people, sit on a bench nearby, and listen to their conversations. These inevitably give you some information about the target or ways you can infiltrate their strongholds and kill them.
 * Of course, since you're reliving someone else's memories, it's possible that he waited for hours to hear the relevant information and didn't pay much attention to the rest or remember it.
 * In Pokémon Diamond and Pearl, when the player is infiltrating the enemy base they will conveniently walk into a room where the Big Bad is giving a speech to his mooks laying out his Evil Plan point by point. (This is partially subverted later when the Big Bad reveals that he was leaving out key points of the plan during said speech.)
 * Listening in on conversations in the Laura Bow games will earn you vital information needed to solve the murders, although there are a few times when you can spy on someone and they're doing something totally harmless, like sitting alone in their room or sleeping.
 * Played straight all the time in Vagrant Story. The main character even has special magic eavesdropping powers.
 * Played with in Tomb Raider: Legend, where—in the first level—Ms. Croft stumbled upon two guards talking about monkeys and how they react to cigarettes.
 * In one of the early levels of the first Splinter Cell game, one of your objectives is to listen in on a conversation with your laser mic. Although you get there in plenty of time, if you don't set your mic up once they start talking, you can miss important parts of the conversation and fail the mission.
 * Paper Mario: The Thousand-Year Door has you listen in on Grubba monologuing a layout for everything he wouldn't have wanted somebody who just happened to be listening to know. He lampshades it at the end by saying "Well, since I'm thinking out loud here, I think I'll put this here paper in this drawer." and then a few seconds later "There, now that that's all settled."
 * Subverted and poked fun at in Max Payne. When the elevator Max is in reaches the designated floor you can sit in and eavesdrop upon some mooks talking. They're discussing... bullet time in television. You can choose to enter bullet time yourself and kill them that way, just for kicks.
 * In Metal Gear Solid 2: Sons of Liberty, there are a couple of sequences where you have to listen in on conversations with a directional mic. You have to keep the aim focused on each speaker as they walk around to hear everything they say.
 * Actually averted in Batman: Arkham City. You can pick up on random thugs conversing with each other when going through the city. More often that not, it's just nonsensical banters.
 * Averted in Covert Action: via Hacking Minigame you can wiretap any location you can find except generic ones or your own office, but in immediate usefulness it's comparable to a single photo of non-secret files: usually gives nothing or a single blip on generic activity meter. Useful hints (locations of other hideouts) are rare, and encrypted messages may be intercepted only if some relevant place was bugged for a while.

Web Comics
"Philia: Check it out, those guys are fortuitously discussing subject matter pertinent to our current task."
 * Schlock Mercenary had it layed straight and lampshaded in this strip. "That was quite a bit more convenient than I could have expected."
 * Played straight when Dean Martin learns Molly's origin in The Inexplicable Adventures of Bob. Then he gets frustrated they don't say more, and settles in to just be a peeping (or listening?) tom instead.
 * Mostly averted by Darths and Droids here (along with instructions for avoiding it in a tabletop game!)
 * Lampshaded in Gastrophobia:

""I have this sudden urge to ask you to remind us all what the plan is, while hoping nobody might be listening.""
 * Beyond the Canopy. Glenn's Call to Adventure comes when he overhears some suspicious characters talk about going to the Forest's Navel. Later, Grandpa eavesdrops on some skeleton guards, and hears just enough to figure out that Glenn has acquired the Remnant.
 * Spacetrawler has a justified example. The intelligent, subterranean Mihrrgoots want to prevent the outside world from learning of their existence, so they have to mindwipe any outsiders who wish to leave, and then deliberately arrange a way for them to "escape" once they wake up from the mindwipe. This involves, among other things, some actor Mihrrgoots talking amongst themselves so the "prisoners" listening to them learn just enough to escape.
 * Averted in General Protection Fault. Nick and Dexter, thanks to the poor quality of their "spy equipment," have difficulty making out what Craig and Sharon are talking about.
 * In Kid Radd, Sheena listens in on Crystal and QB discussing Crystal's scheme, starting with QB mentioning the possibility of killing Radd, while the two are in a room that Crystal thinks is soundproof.
 * Used in Samurai Princess' while Itchyknee-san is searching for the princess and just happens to over hear the Raeka's royal vow of vengeance. PRINCESS FOUND!
 * Lampshaded on I Was Kidnapped by Lesbian Pirates from Outer Space

Web Original

 * Averted in The Saga of Tuck, when many minutes of taped conversations must be screened for the necessary information.

Western Animation
"Fat sailor: I told you, Ernie, we'll take care of him [K'nuckles] like the last guy. Ernie: And just how did we take care of him because...I forgot. Fat sailor: We'll feed him to the shark! Ernie: And then what happens...I mean, after we feed him to the shark? Fat sailor: He dies."
 * In Avatar: The Last Airbender, a bathing Katara swims by Toph and Sokka just as they are talking about her. This may or may not have been deliberately engineered by Sokka in order to get the girls stop fighting.
 * There was also a conversation between Mai and Ty Lee overheard by a pair of Dai Li agents, which reveals that they're from the Fire Nation and not really Kyoshi Warriors. However, it turns out this was done deliberately as part of Azula's Batman Gambit.
 * Subverted in children's cartoon Arthur. Arthur notices that his sister D.W. has been acting strange and upset lately, so he sets out to find what's wrong with her, and eventually places a walkie-talkie in her room at night to hear her sleep-talking. D.W. apparently catches on to this: "I'm sad... because... because... BECAUSE ARTHUR IS A DODO-BRAIN!" (Eventually it turns out that she's upset because she wasn't invited to a friend's birthday party—nothing to do with her brother at all.)
 * This occurs in "Flirting with Disasters" in Danny Phantom where Valerie eavesdrop in time to hear Sam and Tucker talking about the dangers of dating her to Danny. Danny confesses he wants to be her boyfriend regardless which shocks both Sam and Valerie. Luckily, Sam notices Valerie before they could dig deep with their other conversation dealing with Danny's secret identity whom Valerie currently chases.
 * On The Marvelous Misadventures of Flapjack, Flapjack overhears sailors talking about K'nuckles. Camera cut to his shocked expression after every line.


 * Parodied on The Simpsons. While Bart is overhearing a conversation between Principal Skinner and Groundskeeper Willie, Skinner reveals that he is trying his hand at stand-up comedy. He invites Willie, giving him directions to the comedy club starting from the Simpsons' house.
 * In the last episode of The Spectacular Spider-Man, Harry lingers just long enough to accidentally hear Gwen, his girlfriend, and Peter, their mutual best friend, confess their feelings for each other. He's able to use this information to his advantage, however, when guilts Gwen into staying with him.
 * A subversion kicks off the plot in the first postscript season episode of Kim Possible after So the Drama. After Bonnie plants the notion in Ron's head that he isn't good enough for Kim and that it's only a matter of time until she "trades up", he spends a day moping but reassures himself that Kim wouldn't do that. Then he overhears Kim telling Monique that Bonnie is right and that it's time to "trade up". If he waited a little longer, he would have realized they were talking about cell phones and the rest of the episode would have been really boring.
 * In an episode of American Dad, Roger is trying to trick Steve into thinking he's adopted. Then Steve happens to overhear his father Stan saying to his mom, "As far as I'm concerned, we only have one child!" Steve is horrified, not realizing that Stan is actually disowning Steve's sister Hayley due to her anti-gun beliefs. Roger lampshades it: "I just love when crap lines up like that."