Bilingual Backfire

"(in Chinese) I do not like being laughed at."

- Huey Freeman in The Boondocks, right before taking out a Chinese kid with a dodgeball.

When two characters talk about someone else who is present in a language the third party supposedly doesn't speak, and the third party turns out to speak that language just fine, it's a Bilingual Backfire.

Related to Bilingual Bonus and (sometimes) Obfuscating Stupidity. Multilingual readers will realize that this is Truth in Television.

Advertising

 * An ad for... something had two women in a café discussing a rather good-looking man at their table in Irish. Turned out he also spoke the language.
 * There was a Swedish Army commercial, shown in Britain on Tarrant on TV, in which two Army recruits sit on a park bench and tap out sexist remarks about a passing girl in Morse code. Guess what -- she taps out a snappy comeback on a nearby lamp post. Yes, there are women in the Army too.
 * There were two women, they were on the park bench and the male Army recruits were the ones who were passing by, the insulting thing they tapped out on the bench in Morse code was that one of the guys was going to take one of the women and the other guy was going to take "the spare", the two women then tapped out something to the effect of "I don't think so" and "Get lost", and they walked away as the sound of gunfire played on the soundtrack. Whoops, turns out the two feminine-looking women (who were wearing soft pastels and pleated skirts) were in the Army too! (It also aired on an edition of Carrot's Commercial Breakdown.)
 * A similar Snapple juice ad featured two students trying to communicate by snapping the vacuum seals on their bottle caps, until the teacher interrupts them with a message of her own.
 * Another Morse Code gag shows up in a beer commercial from the early 90s: a man uses an LED light to signal to a woman in a bar that he finds her very attractive. Unfortunately, between her and him is a crusty old sailor who does not take kindly to being hit on...
 * There is a Dutch commercial wherein a family enters an Italian restaurant, and the waiters talk about them quite rudely. Cue the father turning around towards them and saying "Hey, pastaclown, if you're done talking to your girlfriends, perhaps you could spare some time for us?" in fluent Italian.
 * Subverted in an ad for Meteor that had an Irish guy try to chat up a girl in Spain by getting his sister to feed him pick up lines in (bad) Spanish, "I admire your dentistry" and "Are you homeless". Then it turns out the girl is actually English, doesn't understand Spanish and finds the language sexy.
 * A 2012 ad for Honda is set in a dealership. The customers start speaking subtitled Chinese (probably so the salesman won't know how much they want the car). They switch to English to tell him they'll take it. He tells them in Chinese to follow him and they'll start the paperwork.

Comics
"Hisako: It's shameful that a killer gorilla passes as a teacher here. Logan: Aren't you shaming your ancestors with your constant complaining?"
 * In Astonishing X-Men, Hisako is training with Wolverine and the session goes badly:

"Lula (in German): "I bet that when you aren't serving dishes, you like to wear women's clothing." French waiter: "No, actually I study German at the Sorbonne.""
 * The look of horror on her face when he replies in her native tongue as he walks away is priceless.
 * In Asterix and the Goths the Gothic chief has his interpreter try to get the captured Getafix to use his magic for them. Getafix bluntly refuses, but the interpreter lies to avoid punishment. Getafix bides his time until Asterix and Obelix show up to inform the chief in Gothic of the interpreter's deceit.
 * In X-Men/Alpha Flight #1, Northstar, who's Québecois, tells Rogue to leave him alone in French. She at first replies in English, then adds, in French: "By the way, sugar, we speak French ourselves in the Mississippi Bayou Country. Can't crowd me out that way." They develop something of an Odd Friendship after that.
 * German comic Lula und Yankee:


 * In a Judge Dredd story where McGruder negotiates closer ties with Traktorfaktori, Traktorfaktori's attendant Judges make several comments on Hershey's and Dredd's backsides in Russian. Hershey and Dredd respond angrily, in perfect Russian.
 * In Maus, this happens on a date between Anja and Vladek; Anja is speaking to a mutual friend in English about what she thinks of Vladek, not knowing that he also speaks English. This is a positive example, though, since she likes him.
 * In X-23, Laura's martial arts tutor spends their lessons talking to her like a normal human being when not speaking English, in direct contrast to his superior's wishes. After this goes on for some time, his superior demonstrates he also knows the language the instructor is using and

Fanfics

 * In Black Crayons, Ironhide begins teaching Annabelle some basics about how to speak Cybertronian. This allows her to listen in and participate on a few conversations she wasn't supposed to understand. This includes Skid and Mudflap's plans to pull a prank on Ironhide,.

Films -- Live-Action
"Prateek (in Hindi):If we do everything, what will this fat buffalo do? Bully(also in Hindi): I know Hindi. A bit. Prateek(in English): Oh crap"
 * In a deleted scene of the Indian film Ra.One. The story starts out in London, where you wouldn't expect people to know Hindi. Unfortunately for Prateek, the school bully he was insulting in hindi also knows a bit of it.

"Advisor: (to Princess) Sanguinarius homo indomitus est, et se me dite cum mendacia. [He is a bloody murdering savage. And he's telling lies] Wallace: Ego nunquam pronunciari mendacium! Sed ego sum homo indomitus. [I never lie. But I am a savage] Wallace: (to Princess) Ou en français, si vous préférez? [Or in French if you prefer?]"
 * There's that scene in Braveheart where William Wallace catches Longshanks' advisor insulting him to Princess Isabelle in Latin and French:

"Mancuso: (in English) What's so funny? Ryan: (in English) Ah, the Captain seems to think you're some kind of... cowboy. Ramius: (in Russian) You speak Russian. Ryan: (in Russian) A little. It is wise to study the ways of one's adversary. Don't you think?
 * Rush Hour: Jackie Chan pretends not to understand English. Allegedly inspired by the Real Life first meeting between Chan and Tucker.
 * And in the second movie, Carter tries to tell a Chinese taxi driver to follow Ricky Tan's car, but the driver keeps responding in Chinese. Frustrated, Carter gives him some money and asks, "You understand that?" The driver looks at the money and says, in English, "Now you're speaking my language."
 * Appropriately enough, the taxi driver was probably telling Carter that he needed to show money first.
 * Then why didn't he just say so in English, seeing as how he obviously speaks and understands it?
 * The third movie also exemplifies this trope when Carter first flirts with Genevieve.
 * In The Alzheimer Case: Vincke and Verstuyft, using Dutch, agree that main character Leddo (who they think only understands French) looks like "he's spent two years lying face-down on the rail tracks." Leddo later bids them farewell with a deadpan: "I'm going to spend two more years lying face-down on the rail tracks."
 * In The Hunt for Red October, Ramius comments in Russian to Borodin that Mancuso is a "buckaroo". Ryan laughs.

Ramius: (in English) It is."

"David Bouchard: (surprised) Tu parles français? [You speak French?] Martin Ward: Non, je ne parle pas français. Je me suis fait installer un gadget au cerveau and I see subtitles under people when they speak. [No, I don't speak French. I had a gadget installed in my brain et je vois des sous-titres sous les gens quand ils parlent.]"
 * The Librarian in The Librarian films usually turns out to know the language.
 * In George of the Jungle, one of the guides makes it very clear that the other guides only speak Swahili. Until it eventually comes to light that they're all completely fluent in English.
 * Variation: in The 13th Warrior, the Northmen constantly talk about Ahmed in his presence, because he doesn't know their language. This trope comes into play when he becomes fluent merely from observing them, just in time to give a witty response after they've insulted his mother.
 * In Belgian movie De zaak Alzheimer ("The Memory of a Killer") two characters, using Dutch, agree that main character Ledda (who they think only understands French) looks like "he's spent two years lying face-down on the rail tracks." Ledda later bids them farewell with a deadpan: "I'm going to spend two more years lying face-down on the rail tracks."
 * In My Fellow Americans, the two main characters run into some Mexicans. One strikes up a conversation, insulting the other man, but after the Mexicans leave the scene the other comes back with: "By the way, yo hablo español muy bien. Dickhead."
 * In Inglourious Basterds, the Basterds' and Frau von Hammersmark's plan of infiltrating the theatre involved them speaking Italian as the Germans do not know the accents (and they wouldn't have to repeat the bar incident), but one of the people they meet is Hans Landa, who knows Italian and is pretty much able to confirm his suspicions about them by their atrocious accents.
 * Earlier in the film, Landa was cautious about this trope but finds that he didn't need to be concerned because the family under the floor didn't react to any of the English he and Pierre La Padite spoke.
 * Done by Cynthia Rothrock's character in the Hong Kong movie Righting Wrongs, when she is insulted by hoodlums and told it's a compliment; one of the hoodlums tries to think of an insult and she gives a suggestion, revealing she speaks Chinese, then beats them up.
 * Hungarian movie Valami Amerika ("A kind of America") revolves around a Hungarian director of TV commercials and video clips, who's trying to convince an American producer of his skills at directing in order to get funding for the movie he's written. Of course, the producer is actually of Hungarian birth, which is revealed at the very start of the movie to the audience, but only much later to the characters.
 * Used as a plot point in the Spanish-language film Ladron que Roba a Ladron ("Thief who Steals from a Thief"). One of the titular thieves pretends not to speak English to an American security guard, who snaps at him "You're in America, speak English." The thief then hears them talking about the security layout of the building, and as he leaves, shoots over his shoulder "Excuse me, senor? You're in America. Speak Spanish."
 * Taking Lives has one as well, though this troper does not recall the specifics. Two of the characters consistently talk in another language, often insulting Angelina's character in some manner. If one pays attention, they can see her reacting early on. Eventually she responds in the same language, leading to a reaction that you may or may not consider "classic" for this particular trope.
 * In Bon Cop, Bad Cop, Bouchard casually abuses Ward in French... until during a meeting with their respective supervisors, Ward reveals that he speaks excellent French and even lived in Paris for a while.

"... and I haven't had sex in forever... Forever is a very long time."
 * My Life In Ruins has this in the embarrassing direction, as the heroine stands complaining about her life in English while standing in line with a group of Greeks, including her bus driver:


 * She then asks in general how many there understood English, only to have half the crowd raise their hands.
 * In the original version of The Taking of Pelham 123 Walter Matthau is showing a group of Japanese businessmen (representing the Tokyo Metro) around the New York subway command centre. Throughout, he addresses them in various insulting ways, such as: "Come this way, monkeys!" At the end of the tour, they thank him - in fluent English.
 * In one of The Pink Panther movies, Inspector Clouseau goes to Germany (or some German-speaking country) and tries to rent a room. He asks the clerk, "Do you have a rim?" "A what?" "A rim" The desk clerk doesn't understand. Clouseau pulls out a French/German (English/German??) dictionary and asks for a 'zimmer'. "Oh," the desk clerk responds in English, "a roooom" [It's funnier to watch then to read]
 * Invoked and parodied the 90's comedy-parody Fatal Instinct: Lana and her lover meet in a park to plan a murder. Since there's an old black guy sitting on the next bench, they carry out their conversation in Yiddish. When the old man offers some advice, Lana gawps at him and asks "You speak Yiddish?!" He replies "No, but I can read the subtitles."
 * Averted in the movie Four Weddings and a Funeral, when Carrie and Charles encounter his deaf brother while out shopping. The two men proceed to converse in sign language, during which Charles complains about Carrie's impending wedding (he's in love with her) and denounces her fiance, while his brother "comments" on her "beautiful breasts", all the while telling Carrie that they're offering compliments and congratulations. One watches the scene expecting that any minute now, it will be revealed that Carrie knows sign language herself and has understood everything--but it never happens.
 * It would have been really surprising if she had, the sign language used in the US isn't related at all to the one used in the UK.
 * The Peacemaker. George Clooney's character introduces Dr Kelly to his Russian contact, who says to Clooney in his own language, "A beautiful woman with a PHD. You're way out of your league." She butts in to reply in Russian, "You have no idea."
 * Also nicely done earlier in the movie, where Clooney hands Kidman a list of names of Russian military personnel -in Russian. On her remark that the list is useless, Clooney says that the list is in Russian, only to be told by Kidman that the list is missing ranks and other details, in fluent Russian.
 * In The Love Bug, Tennessee speaks to Mr. Wu in Chinese (or an approximation of it), and Jim asks Tennessee to ask Mr. Wu if he would let him drive Herbie in the El Dorado race, with the condition that Mr. Wu will keep the winnings. This prompts Mr. Wu to say, in English, "Now you speak my language!".
 * In What's Cooking, a film about four families on one street corner at thanksgiving, the Hispanic family are introduced to the Vietnamese boyfriend of the daughter. While fetching down a high up dish in the kitchen, all the female relatives compliment his 'looks', and are very embarrassed when he turns out to speak perfect Spanish.
 * 2003's Under the Tuscan Sun features a scene where a handyman is doing work on a villa in Italy while the three women who are staying there discuss his good looks in English. When he's done with the work, he smiles and thanks them in English, and tells them that he's an American.

Literature
"Fudge: Wait, you can speak English?! I've been trying to mime things all day! Bulgarian Minister: Vell, it vas very funny..."
 * In Lords of the Bow, Chen Yi provides transport to Khasar, Temuge, and Ho Sa. Chen Yi puts up a pretense of only speaking Chinese, but when they get to his house and the travellers begin discussing how to deal with him, he decides to reveal that he also speaks decent Mongolian.
 * Me Talk Pretty One Day by David Sedaris has a story about this. Sedaris is an American expat living in France, and while he's on the Paris subway an American tourist starts talking about him to his (the tourist's) girlfriend, saying that he smells bad and telling her that he is a pickpocket. At one point he tells his girlfriend that the man Sedaris was with was his partner for theft; the man is Sedaris's boyfriend. Sedaris never confronts them - he just spreads the worldwide.
 * In Mary Stewart's Merlin Trilogy, the title character is captured by some bandits who are discussing in their language what to do with him, thinking he doesn't understand, until he tells them in their own language who he is and what will happen to them if they don't release him.
 * It's actually better than that. They'd been trying to start a fire and having no luck, because it'd been raining all day and the wood was soaked. When Merlin finally let them know he spoke their language, all he said was, "Stand away from the fire." Then he showed them who he was and what he could do to them by igniting a massive fire with a glance.
 * The Bulgarian Minister of Magic in Harry Potter does this just to humiliate Fudge.
 * Apparently Fudge's sign language was funny.

"I cannot remember the epigram exactly, but the sense of it was: "Antonia is old-fashioned: she does not buy a pet marmoset at great expense from an Eastern trader. And why? Because she breeds them herself." Athenodorus thought for a moment and replied severely in the same metre: "Antonia, so far from buying a pet marmoset from Eastern traders, does not even cosset and feed with sugar-plums the poor child of her noble husband." Augustus looked somewhat abashed. I should explain that neither he nor Athenodorus, to whom I had always been represented as a half-wit, guessed that I could understand what they were saying. So Athenodorus drew me towards him and said playfully in Latin: "And what does young Tiberius Claudius think about the matter?" I was sheltered from Augustus by Athenodorus's big body and somehow forgot my stammer. I said straight out, in Greek: "My mother Antonia does not pamper me, but she has let me learn Greek from someone who learned it directly from Apollo.""
 * In Jingo, Unseen University awarded visiting Klatchian Prince Kufurah a "Doctorum Adamus Cum Flabello Dulci", Doctor of Sweet Fanny Adams. It's made clear that the visitors are quite as learned in Latatian as the Ankhian scholars.
 * The Klatchians are smarter. When the Prince meets with Lord Rust he first introduces a local proverb in Klatchian, which actually is just "Can you understand me?" When Rust's translator can't figure it out, he starts with the insults, again pretending they are proverbs. "As we say in Klatch, I can't believe this man"."
 * Likewise, in Unseen Academicals, a dwarf shopkeeper pretends not to speak Morporkian and amuses himself by insulting his customers in Dwarfish. At least, until Nutt calls him out on this behavior in letter-perfect Dwarfish.
 * And, in "The Fifth Elephant", Vimes notices an Uberwaldean guard who claims not to speak Morporkian watching him and realizes that he must understand Morporkian after all. Just to double-check, he tells his interpreter to tell the soldier that he has a fly on his nose, and sees his hand start to move toward his nose before he catches himself.
 * Danaerys of A Song of Ice and Fire pretends to not understand the language when she is in the Slaver Coast cities and is therefore underestimated by the native speakers.
 * In his autobiographical novel, My Happy Days in Hell, György Faludy tells a story about two retired Latin teachers, who publicly talked to each other in Latin, criticizing the totalitarian dictatorship of 1950s Hungary. However, a professor of Classical Philology heard them, and informed the authorities.
 * In Eric Ambler's novel The Light of Day, the Anti-Hero gets captured by the Turkish State Sec and his interview is being conducted in French, a language both he and the officer speak. At one point, he starts ranting in English, and the officer reveals he's fluent in that language as well.
 * Bill Bryson and his traveling companion Stephen Katz found themselves on the wrong end of this trope as teenagers, as recorded in Neither Here Nor There, when a Turkish restaurateur Katz had just insulted rather graphically "turned out to have spent thirteen years working in a Turkish restaurant on the Tottenham Court Road, and escorted us from the premises with the aid of a meat cleaver."
 * Played with in the Shadow pulp novel "The Golden Pagoda". At one point, the Chinese crimelord Li Hoang personally executes the guard who not only failed to keep Harry Vincent prisoner, but begged for mercy.
 * Averted in The Death of the Vazir Mukhtar, when the polyglot protagonist turns out to not know Tatar, allowing the two tatars to mock him behind his back in the Tbilisi bathhouse.
 * In the Circle of Magic quartet by Tamora Pierce, when the four main characters first meet at Discipling Cottage, Briar rudely asks why Daja, a Trader, is wearing red for mourning. After Daja explains, and substitutes the rude word for a non-Trader (kaq) with something else, looks over at Sandry, who also speaks the Trader language, and says in that language, "And he is a kaq." Briar immediately says in Trader-talk, (paraphrasing here) "I haven't been living under a rock all my life. And I'm not stupid."
 * In Rudyard Kipling's Kim, many Indians amuse themselves by acting subservient to the British while hurling terrible insults at them in Hindi. At one point a street-sweeper does this to Kim, who is dressed as in European dress, which turns out a mistake. In a later chapter, when Kim speaks disparagingly in Hindi about a couple of Europeans in their presence to the lama, the lama gently chides him that it is unworthy to take advantage of other people's ignorance in that way.
 * A sci-fi example occurs towards the end of Barry Longyear's Enemy Mine when the human hero is traveling to the Drac homeworld and fluently and profanely responds to a fellow-traveler Drac's insults; the Drac's companions have to physically restrain him.
 * In the opening section of The Vor Game Miles Vorkosigan never lets on to a bunch of Greek speaking soldiers who have been insulting him that he understands every word they're saying.
 * In the first Magic Kingdom of Landover novel, Magic Kingdom for Sale-- SOLD!, Ben is negotiating with the leader of a tribe of dangerous and brutal crag trolls, using his court wizard Questor Thews as a translator. When negotiations go badly, he's forced to threaten to summon the king's champion, the Paladin, to defend his party. When Questor voices doubt about this, Ben angrily insists that a bluff is their only chance to escape at this stage- and Questor notices that although the troll leader doesn't speak Landoverian, he apparently understands it. And then things get bad.
 * In The Company Novels, at one point Mendoza and her fellow go to Venice, where they make whoopee in a canal boat. The gondolier comments loudly on the action to his fellow gondoliers, assuming the pair don't speak his language. After they're done, Mendoza tells him in his own language exactly what he can do with his pole. And doesn't tip.
 * In Malevil, temperamental old woman, La Menou, is not pleased that another old woman, La Falvine, survived World War III and will be living with them. She proceeds to rant at Emmanuel for bringing La Falvine home; accusing her of being too old to work, gluttony because she's fat, and an incestuous relationship with her Evil Poacher son, all in their regional patois so that the "foreign" woman won't understand. La Falvine bursts into tears, argues back in patois, revealing she's a local and a distant cousin.
 * In The Ugly American, American diplomats hire natives of the fictional war-torn Southeast Asian country to work as servants in their embassy. A visiting Chinese diplomat discovers and explains that at least some of the servants are spies pretending not to understand English.
 * In A Desert Called Peace, when Carrera is drowning his sorrows over the wife and children killed in a terrorist attack, he demonstrates to a woman insulting him in Spanish that he, too, speaks the language, in spite of a conversation with the woman's friend being in English.
 * In one of the Perry Mason novels, Perry is being arrested. He advises Della, in legal terminology, to track down a particular witness. When she does, she finds a note saying "Just because a police officer has a cauliflower ear, doesn't mean he didn't take debate in high school."
 * Julius Caesar and Mhorbaine both do it to each other in Emperor: The Field of Swords. Mhorbaine initially speaks only in Gaulish, preferring not to let Caesar know he understands what the Romans are saying in Latin. For his part, Mhorbaine is unaware that Caesar's Spanish scribe, Adan, happens to know Gaulish, which means Caesar is able to find out the Gauls are talking about when they think they're in private.
 * Played with in Shogun. Blackthorne and Mariko speak to each other in Latin when they don't want to be understood by Japanese or Portuguese speakers. Unfortunately, some enemy samurai are Catholic, and they also speak Latin. Blackthorne figures out who was eavesdropping by reciting a prayer and waiting for an "Amen".
 * In Ngaio Marsh's novel Death of a Peer, during a murder investigation, the upper-class Lamprey family decide to converse amongst themselves in French while deciding on the not-exactly-true story they're going to tell the police, blithely assuming that the humble constable left to watch over them won't be able to understand a word. Unfortunately for them, the constable in question lived in France until he was 15 years old, and keeps perfect notes of everything they say.
 * This happens at King Fulrach's formal dinner in the first book of Belgariad. Silk and Garion insult the Earl of Seline in the Drasnian sign language, in which the Earl turns out to be fluent. Silk was aware of this, however, and the Earl understood that Silk was just having a laugh at Garion's expense.
 * In Juliet Marillier's Daughter of the Forest, the main character is Irish but understands English perfectly well. She fluently speaks both languages, except that for most of the book she's not allowed to speak. Three English men pick her up and take her to England from Ireland. She is quite seasick on the way there, and two of the men, though helpful, make comments about it, thinking she doesn't understand. The third one, who knows she does understand, debates how long ot let them go on before letting them know that she does, in fact, understand what they're saying.
 * In I, Claudius (the novel), the young Claudius overhears Augustus and Athenodorus talking about him in Greek. The following ensues:


 * Thanks to Aide, Belisarius can become fluent in languages very quickly just by listening to them. This becomes a critical factor during his mission to India when the Malwa and their allies don't realize until too late that he can speak Hindi, Kushan, and several other languages like a native, and he makes the effort to not let them know this until it's too late.
 * There's a CSI: NY tie in novel where Lindsay and Stella are processing a scene at a bakery, and the owner uses a derrogatory Italian term for a female cop. What he doesn't realize is that Stella speaks some Italian, and though she's rusty, she knows exactly what he's saying.

Live-Action TV

 * A kind of example from ER: A eldery Chinese woman shows up with a serious illness that is quickly identified as symptoms from a brain tumor. It turns out that her son and daughter-in-law already know this, but are keeping it from his mother since they thought it would kill her. The doctor disagrees, but their argument quickly becomes a moot-point since they argued in front of the mother and "Cancer" tends to mean the same thing in all languages.
 * Ros na Rún once had an Indian character who spoke primarily in English, while two of the women had a rather insulting conversation about him in Irish. Turns out he spoke Irish pretty well.
 * In Scrubs, when Marco was first introduced, he pretended to only speak Spanish to annoy Turk. Turk eventually goaded him into revealing he spoke English.
 * In a later episode, Turk decided to surprise Carla by telling her he'd learned Spanish, but then decided to keep it a secret for a bit so he could listen in on her secret conversations and appear to be a more attentive husband. This didn't go entirely as planned.
 * A sketch from John Leguizamo's short-live sketch show House of Buggin' used this. It took place at a Mexican restaurant wherein a mariachi band was going around to the tables and singing. Subtitles indicated that the lyrics they were singing (in Spanish) were mocking the patrons, such as "Little do you know where that meat came from -- enjoy your burro burrito!" And the patrons would clap, and they'd move on to the next table. Until they got to one where the very muscular patrons sang back at them, in Spanish: "We speak fluent Spanish and understand everything you just said!"
 * Studio 60 On the Sunset Strip: The businessman from Macau did this.
 * In Lost, the Korean woman Sun Kwon pretended not to understand, when in actual fact she had had English lessons. A very serious use of this trope.
 * Her husband has this too in later series, but in an innovative way. The time on the Island made him understand English without knowing to speak it too well. After his realization, he eavesdropped on many conversations and reacted in regards with those that concerned him. IIRC, he confesses to his wife a season or two later.
 * At first the "Alternate Universe" version of Jin didn't seem to speak English at all, but ended up learning it really fast.
 * In Phoenix Nights, Corrupt Corporate Executive Keith Lard rhetorically asks one of the club owners if he knows the Mexican for "Help! Let us out! We're burning!" He then walks away... and the club owner translates it behind his back.
 * In an episode of The Tudors, Anne Boleyn is washing Queen Katharine's feet when Katharine curses her in French, calling her a whore for returning King Henry's affections, to which Anne replies in English that she is no whore.
 * This is a perfect Case of Did Not Do the Research since Anne Boleyn was raised in the French court, and thus obviously fluent in the language. However, she didn't speak Katharine of Aragon's native language, Spanish. Which makes the Queen's choice to curse in French all the more confusing.
 * A perfect case of Did Not Do the Research for at least Katharine in the example. French, at the time, was considered the courtly language, much like Latin was the language of the Catholic Church -- it didn't matter so much what your native language was, you were probably speaking in French amongst royals. It's quite reasonable that Katharine would have defaulted towards cursing in French. That said, even without knowing where Anne Boleyn grew up, she should have assumed Anne knew at least some French, being in a royal court.
 * The show specifically did mention Anne's background in the French court back in the earlier episodes of Season 1 and in Season 2, so this might either have been a mistake on Katharine's part written intentionally by the writers, or Katharine was intentionally insulting her.
 * The title character of House speaks a variety of languages, and uses this to bust a Chinese teenager who is using her role as translator for her mother to get herself birth control pills. House doesn't let on at first that he speaks Mandarin.
 * Turns out, he really can't though. He can count to ten, ask to use the restroom, and tell people their daughters are pregnant. Hilarity Ensues as House walks out the door.
 * Or can he? An early season 8 episode has him conversing multiple lines in mandarin with a buisnessman. Far more than the above would imply him capable of.
 * In one episode of How I Met Your Mother, Ted bumps into a woman he used to date, but dumped because she talked too much, and her new boyfriend, who turns out to be deaf. While she attempts to interpret between Ted and the boyfriend, Ted is communicating with him through sign language behind her back.
 * One episode of Seinfeld revolved around Elaine getting George's father to come to her Korean nail salon to translate the insults they were saying about her. It turned out one of the women who worked there was his old girlfriend from when he was a religious icon salesman in Korea.
 * George and Jerry attempt to invert this trope. When talking about asking Jerry's deaf girlfriend to use her lip-reading talents to find out why George's girlfriend dumped him, the two keep trying to hide their mouths so that she can't figure out what they're talking about--but she does anyway.
 * Happens occasionally on Stargate SG-1, understandable considering Jackson knows something like 30 languages. Colonel Fanboy Mitchell manages to catch Jackson on this in one episode, when Jackson and a Chinese diplomat are conversing about the team in the latter's native tongue.
 * Inverted when they go back in time and are captured by the US military of 1969. The officer in charge asks (in Russian) if they are Soviet spies. Daniel naturally responds "Nyet", and then a moment later realized it was a mistake.
 * In an episode of NCIS, Gibbs, Ziva, and McGee are in a hotel room while a foreign prince from Saudi Arabia and his brother argue in Arabic in the background. Ziva tells Gibbs that they "do not know that I speak Arabic", and then translates for him until the prince's last words, to which she says "That is too disgusting to translate."
 * Interesting variation in Babylon 5: Marcus tells Ivanova some of his deep feelings for her in Minbari, knowing she doesn't speak it -- and not knowing that she has an eidetic memory, which lets her remember everything he said until she learns Minbari a year later and finds out the meaning.
 * Another Babylon 5 example: Delenn and a Minbari Captain are captured by human individuals violently loyal to Earth (despite/ignorant/because of President Clark's recent fascist direction). They quietly start assessing the situation and planning an escape strategy in Minbari, only for one of the captors to interrupt them. (He didn't actually say anything in Minbari, but he made it clear that he understood exactly what was being said.)
 * Could they have not switched one of the other two Minbari dialects? Chances are, the guy wouldn't know it.
 * It's has been insinuated on occasion the while different, the basics and roots of the dialects are all still the same.
 * In one episode of Frasier, the title character has been trying to win the affections of his matchmaker from her boyfriend. When he crashes their dinner-date, he tells the maitre d' in French that the boyfriend won't be staying; the boyfriend responds, also in French, that he will be.
 * A variant in the pilot episode of Fringe. We're introduced to Peter Bishop speaking to a pair of investors in Iraq about rebuilding an oil pipeline. He tells them that he speaks fluent Arabic, among his other qualifications. One leans to the other and whispers in Farsi that they should hire him for a substantial amount. Peter replies, "I also speak Farsi. And that amount would be fine."
 * A variant in the White Collar episode "All In": Peter very awkwardly approaches a group of Chinese women to ask for information. They chatter freely amongst themselves in Chinese, but won't say anything in English to Peter. Turns out he actually doesn't speak Chinese--but he tape-recorded the conversation, and can have it translated.
 * In an episode of Bones, Booth and Brennan meet the children of a wealthy businessman, who insists that his kids learn Chinese, given the rise of China as an economic power. They turn to each other and start insulting Booth in Chinese. Bones, having travelled everywhere, is able to understand and translates the insult.
 * A variation happens in Castle, when the eponymous author infiltrates an underground gambling den in order to assist Beckett in a murder investigation. Himself a pretty good poker player, he pretends to be a newbie, a rich writer looking for inspiration for his next novel. The Russians he's playing with talk among themselves in Russian, saying how they're gonna take him for all he's got. While Castle isn't bilingual, Beckett, who is listening via a wire on Castle, has spent several months in Kyiv, Ukraine, as an exchange student and is able to understand them. However, Castle, even without knowing what they said, cleans them out.
 * In the All in The Family episode "The Elevator Story", Archie is stuck in an elevator with several people, including a Puerto Rican man. He tries to use the elevator phone, while the man tries to get his attention. Archie says "Can somebody translate what I'm saying to this spic here?" The man responds: "Is not necessary, mister, this spic is speak English!" Archie, however, is completely unfazed.
 * In an episode of Whos the Boss, Samantha's boyfriend helps her cheat on a French exam. While they're in the kitchen later with Mona, Samantha thanks her boyfriend in French for helping her cheat, unaware that Mona knows French also.
 * In an episode of JAG, Sarah Mackenzie is on a submarine as part of a fact-finding mission to determine whether women should be allowed to serve on submarines. A sailor looks at Mac and says, in Russian, "Do you think they'd look like her?" Another sailor says, also in Russian, "No, more like sperm whales," and they both laugh. Mac, who is fluent in Russian, says, "Let me know if you see any sperm whales. I thought they were rare in these seas."
 * In another, where she and Harm travel to Russia, two hotel clerks make some crude remarks about him 'being able to afford' a woman like Mac (they are in civies). Mac steps forward and rattles off a quick, untraslated, reply, then tells Harm not to bother trying to look up what she said in his phrasebook.
 * In an episode of Sea Patrol, the crew were attending a event at a French embassy and when Spider asked for a beer the French waiter pretended not to know English and said, "I'm proud of my bum when I see your face". Bomber came to his rescue and told the guy "Don't mess with me, w*****!", and got his beer and one for herself. She then told Spider that she could just speak high-school French.
 * In one episode of Skins, the group went to Russia. Anwar rescued a Russian woman from her abusive household and when she was in his room, he proceeded to talk about the sexual acts he'd like to perform with her. Turns out she spoke English and understood every word he said.
 * Happens again in the S3 premiere when Cook discovers that the girl he and JJ are hitting on is deaf and a lip reader. Cook covers his mouth while describing everything he'd do to the girl to JJ, only to have the girl's translator sign everything she hears back to her. It does not end well for Cook.
 * And echoed in the S4 finale when Thomas is pretending to teach Katie French. Cut to Pandora sat outside the bedroom with her new A-level results - including an A in French - and then we get the subtitles showing us what he's really saying...
 * In the pilot of City Homicide Matt pulls this on an Italian hotel manager reminding him that he's in the middle of a murder investigation. He later reveals that his mother was Italian.
 * An episode of Star Trek: Deep Space Nine has Klingon soldier stopped by Odo, who happens to have been speaking with Garak at the time. The Klingon says something (roughly translated as 'does your mother let you walk around in that uniform?'). Garak responds with "I don't think Constable Odo HAS a mother."
 * An episode of Just The Ten Of Us had the Lubbock family boarding a Spanish exchange student who promptly made advances to all four of the teenaged daughters, who each believed that they were the first to successfully teach him English--only to have it turn out that he already knew and merely used the supposed language barrier as a tool of seduction. The funny thing is, he reveals this when he gets fed up with two other characters bad-mouthing him in English and blurts out an angry retort. His satisfaction at embarrassing the other two is short-lived when they rapidly realize what a cad he's been in leading the girls on.
 * An episode of Baywatch had a rebellious lifeguard mouthing off in French to a senior lifeguard who was disciplining him. She coldly informs him that she understands French (though the audience never finds out specifically what he said) and promptly ups his punishment.
 * An episode of The Golden Girls had Sophia in the hospital and Stan and Dorothy trying to get information. When Stan tries to speak to one of the orderlies, the man tells him in broken English that "the men's room is down the hall" and "the cafeteria is closed". But as soon as Stan hands him a wad of cash, the man instantly tells him in perfect English that "someone will be with you in a moment."
 * Inverted in an episode of Strong Medicine. A young Frenchwoman is brought to the hospital. Andy offers to treat her since she is fluent in French (and other languages). But when Andy questions the woman about her symptoms, she seems confused by her responses. Suddenly, Andy switches back to English and tells the girl to cut the crap--she's been asking her about pain and/or trouble breathing and the girl keeps responding with "oui" (yes) or "non" (no), essentially telling her that she can't breathe at all. As it turns out the girl isn't French, just an actress, and can't understand a word that Andy's been saying.
 * In True Stories of the ER, a young female doctor is sent to a Greek woman and her family. Little did the family know, the doctor spoke Greek fluently. The patient only speaks Greek and begins insulting the doctor and refusing tests. Not wanting to offend them, she waits until the woman is cured until she reveals she speaks Greek too.
 * A variation in Ned's Declassified School Survival Guide. Moze attempted to insult the opposing volleyball team and not get ejected for poor sportsmanship by insulting them in Dutch. However, the it turns out that the referee happens to be Dutch himself and Moze ended up getting ejected from the game.
 * In the Inspector Morse episode Who Killed Harry Field?, a German witness tries to stall Morse by claiming (probably falsely) that his English isn't up to being interrogated. Morse switches to German and carries on questioning him.
 * Cousin Skeeter - Skeeter has just...knocked over a T-Rex skeleton or something. A couple of women say-I believe in Portuguese-"The short one is in trouble" as they laugh amongst themselves. Skeeter replies in Portuguese "Hey! I'm not short! I'm still growing!"
 * During an episode of NCIS: Los Angeles, when a Japanese executive, after belittling Sam and Callen to his entourage and calling a woman in Japan to tell her to "answer the cops questions", Sam informs him in Japanese "You wish I was just a cop." He then takes the phone and converses with the woman in fluent Japanese while the executive stares.
 * On The First 48 a suspect called his home from the Miami Homicide interrogation room and told his father, in Creole, to hide the murder weapon, even describing it so the father knew what it was. The detectives, watching on a monitor in another room, could barely restraining themselves from howling with laughter as a Haitian-born detective translates this for them with a big-ass grin on her face.
 * In Season 5 of Weeds, Shane busts out some unexpectedly perfect Spanish while two Mexican drug addicts are attempting to rape his step-sister. "You guys better get out of here before I rape you in the ass with this knife!" is what he shouts, brandishing a knife out of nowhere. Let's just say the rapists quickly scramble away.
 * On Law and Order, Detectives Briscoe and Green are asking the girlfriend of a murder suspect about his whereabouts. She claims to not know, but when her phone rings, proceeds to talk to the other person in Spanish, obviously assuming that neither detective will understand her. When she hangs up, Detective Green talks to her in Spanish, revealing that he knows the language and HAS understood everything she just said to other person. The audience never finds out exactly what either of them say, but given her Oh Crap reaction and Green's tone of voice, it seems obvious that she was lying and that Green is warning her to cooperate, lest she face jail time herself.
 * An inverted version on Law and Order: Criminal Intent. Several deaf persons are suspects in the murder of a doctor who performed cochlear implants. In one scene, the detectives are at a skating rink, observing the "conversation" between two of the suspects. When Goren asks the police interpreter to tell him what they're "saying", the man refuses, but Goren points out that in a public place, the two have no right to privacy. Unfortunately, the two realize the cops are talking about them--Goren's attempts to hide his mouth so they cannot read his lips tip them off, and promptly tone down their signing gestures, leaving the interpreter unable to decipher what they're "saying". A later scene has another suspect "talking" with his lawyer. This time it's the district attorney who demands that the interpreter reveal the details of the "conversation", trying to use the same "in plain sight" loophole, but this time, the interpreter stands firm in his refusal to translate, as that would violate attorney-client privilege.
 * Another episode had a Hispanic woman warning her little girl in Spanish that "people with big eyes get hurt", obviously fearing for her daughter's safety should she reveal what she knows about a murder. At this point Detective Barek reveals her fluency in Spanish by gently urging the woman to let her daughter tell what she knows.
 * A variant in the Republic of Doyle episode "Mirror, Mirror". Several scenes establish that Jake Doyle doesn't speak French. At the end of the episode, love interest Sgt Leslie Bennett claims that a francophone police officer isn't her type, then switches to French to say . Jake asks her what she said, and adds "You know I don't speak French." Bennett refuses to translate and leaves. After Bennett is gone,.

Music

 * Wee Papa Girl Rappers' 1988 hit "Wee Rule" mentions the narrator being insulted and sworn at in French by somone who doesn't know she's "passed exams in French".

Myths & Religion

 * Joseph does this to his brothers in The Bible. They don't recognize him, so he speaks Egyptian to them through an interpreter even though he knows what they are saying.

Professional Wrestling

 * Believe it or not, there was actually a feud based around the Bilingual Backfire; there was a brief period of time where WWE champion Maryse would come up to Gail Kim and talk about how great a wrestler she is and how she respects her, etc., and then say something in French. This went on for a few weeks until Kim attacked Maryse, revealed she was fluent in French, and knew the entire time that Maryse was trash-talking her to her face.

Sports

 * Older Than Radio: A Deaf baseball player named Luther "Dummy" Taylor (he played from 1900-1908, so "Dummy" referred to Mr. Taylor's inability to speak) used sign language to pester Hank O'Day, an umpire he had a feud with. O'Day spent his time learning sign language, then after one taunting, told Taylor to go to the clubhouse and pay $25 -- using sign language.
 * Juan Pablo Montoya's first Formula One pole position. ITV commentator Martin Brundle asked him, 'Congratulations, how's it feeling?' Montoya (who is from Columbia) was rude enough to reply in Spanish, then rubbed it in by asking, 'What d’you think of that?!' Brundle's reply? 'Si, es ist muy bien!'
 * I don't get it. The guy answered him in Latin? Because That's not Spanish.

Stand-up Comedy

 * Ventriloquist Jeff Dunham does an odd play on this. At one point his puppets Peanut and Jose Jalepeno on a Steek begin conversing with one another in Spanish. Jeff complains to them that he doesn't speak Spanish. Lampshaded by the puppets when Jose begins singing The Twilight Zone theme and Peanut remarks "Picture if you will..."
 * Henry Cho (a Korean-American comedian from Tennessee) has a routine about how he went to South Korea on vacation and was approached by another American tourist who asks him, "IS THIS THE BUS-Y THAT GOES-Y DOWN-Y TOWN-Y?!" Response: "I reckon so. So, what's yer name...?"

Theater

 * In the first scene of The King and I, the kralahome initially speaks to Anna through an interpreter; however, when she refuses to be treated as a doormat, he starts speaking in perfect English. Apparently he just wanted to mess with her.
 * Happened on the Nuits De Paris sketch of Les Luthiers with French.
 * Larry Shue's play The Foreigner is made of this trope. A tourist pretends to be a foreigner who doesn't speak English so he doesn't have to have small talk conversations with others. Since he doesn't speak English, people have various conversations in front of him which eventually reveals a plot to drive the owner of the lodge out and use the place for KKK meetings.

Video Games
"Magistrix Larynna: (in Thalassian) Dor shar'adore da shando! [I'm Surrounded by Idiots!] Anchorite Karja: The magistrix will be happy to know I'm fluent in Thalassian. Your courtesy is not lost on me."
 * A number of NPCs from rival but allied factions in World of Warcraft have a long, repeating argument in Netherstorm. At one point one of the blood elves mutters something in her own language that one of the draenei says she understood:

"Sabatier: (in French) You arrogant Americans, think you can run the world as you see fit. Sawyer: (also in French) We have a war to win, and I will do what I deem necessary."
 * In World in Conflict, a pre-mission cutscene has Colonel Sawyer (American) and Commandant Sabatier (French) arguing, in English, about letting an American officer command NATO forces. Sabatier voices his annoyance in his native tongue.

""Mr. Armstrong? My apologies, but me habla espanol, and 'por favor' is Spanish.""
 * In the PC adventure game The Last Express, Robert Cath speaks English, French, and German, and can understand when two gossiping ladies switch their conversation to French so that they can talk about him when he's in the room.
 * Jean Armstrong of Phoenix Wright: Ace Attorney: Trials and Tribulations mostly uses Gratuitous French. Partway through one cross-examination, however, he shouts, "Por favor!" The Judge responds:

Web Comics
"Tom: Mom, this is Alex Alex: H-Hi. Mom: Hablas Español? Alex: Wha? Mom: Usa condones. Eres hombre ahora pero todavia puedes quedar embarazada. Tom: MOM! Alex: What did she say? Tom: You do not want to know."
 * Under the Lemon Tree (now Goblin Hollow) had this happen in Navajo.
 * On this page of Gunnerkrigg Court, Gamma mutters to herself in Polish, calling Antimony and Kat stupid. Annie replies in Polish, "That wasn't very nice."
 * Averted in a later scene where we learn that Gamma does not understand English, and depends on her telepathic bond with Zimmy for interpretation...
 * Averted in the logical way in Khaos Komix:


 * This episode of Megatokyo has Piro supposedly translating what Largo is saying to Kimiko, only since what Largo is saying is mostly insane rambling, he is instead making up reasons why they keep Ping around... then Erika, who is also bilingual, shows up.
 * Kevin and Kell: I can speak feline too, you idiots.
 * In Dominic Deegan, Luna discovered that while Hobgoblins can't speak English, they can fully understand it. As you can see.
 * One comic in Exploitation Now had Jordan and Bush hitching a ride on a bus full of Asian girls from an anime con. One of the girls in front of them notices the two and seeing Bush, thinking she a fellow Asian (since Bush is half Asian) starts to mock Jordan in her native tongue thinking Jordan can't understand her. However it turns out Bush can't understand the language but Jordan can and quickly lets the girl know she not amused.
 * Sandra in this (NSFW) Ménage à 3 is unconcerned about discussing her private life with Matt because she assumes that Senna, who is from Brazil, speaks "Brazilianese". She does, plus four other languages.
 * At one point in Order of the Stick, the Order is facing a dragon while Vaarsuvius has been Baleful Polymorphed into a lizard from a previous encounter. Vaarsuvius laments their own present uselessness in the encounter to themself, and the dragon empathizes in Lizard.

Web Original

 * Subverted on Elevator: Harold doesn't know Spanish, but he does know how to say "Hey! I know what you're saying" in twenty languages.
 * In The Guild, when Kwan the Korean programmer insults his opposing team in Korean, and Vork, leader retaliates...in a language that is barely recognizable as Korean...though to be fair the translator's Korean isn't that much better.
 * (The Customer is) Not Always Right got this all over the place, naturally. Including one minor Mind Screw and a case pretending to be trilingual.

Western Animation
"Bart and Lisa: ...Ap-cray."
 * In The Simpsons, Bart and Lisa try to have a private conversation in Pig Latin. Marge mentions that she was using it since before they were born.

"Kasnian Soldier: [You can't understand what I'm saying and I wouldn't tell you anything if you could.] Batman: [I can... and you will.]"
 * Used in the DCAU Justice League cartoon:


 * In Frisky Dingo, ancient Chinese sweatshop worker Old Spice is eventually revealed to speak English after entire episodes of only communicating in Chinese and having Xander Crews (who knew he spoke English) translate for him. This only came to light after Killface insulted Old Spice's "car" (Crews misheard Old Spice, who was actually talking about his wife) and Crews berated him. "What does it matter what I say about his bloody car?" "Well, he speaks English!" "... You speak English?" "Yes!"
 * This is also played with in Stroker and Hoop, where Columbian drug lords force Double Wide to take them to Stroker and Hoop, who are hiding in The Deep South. On the way there, they talk about how they'll kill him before moving onto them in Spanish before Double Wide says he wishes he didn't speak Spanish.
 * Playing on a similar scene from the film Rush Hour, the first episode of Jackie Chan Adventures has newcomer Jade not speaking English at first, but later it turns out she knows perfect English to the surprise of Jackie.
 * During a high stakes kickball game on The Boondocks pitting Huey against a team from China, the Chinese team captain Ming tells Huey that if she lose she might go to prison camp. The captain's teammates talk to each other about the lie and insult his play. Anyone with any knowledge of Huey's interests wouldn't be too surprised to know he understands Chinese. Cue Kicking Ass and Taking Names.
 * Happens once in American Dragon: Jake Long between Jake's father and Gramps.

Real Life
"American guy: Could you stamp my passport, please? It's a hobby of mine. Passport checker to coworker, in German: These damn Americans always want something. Look, they've all got booze and bags and t-shirts. Now they want stamps. American girl: Sir, I'd like mine stamped, too. Passport checker, in German: I bet that girl was here to fuck guys. American girls become sluts in Europe. American girl: Sir, that's not very nice! Passport checker, still in German: I hate it when they know German. Then we can't talk about them!"
 * There's an anecdote about Haim Saban that goes as such: During the 80's, Saban was attempting to buy Kiss Licensing rights, and was meeting with Gene Simmons with Avi Arad at his side. At a certain point in the meeting, Saban turns to Arad and says, in Hebrew, "now we will gut him." Simmons responded by saying "You asshole, I'm one of you" in Hebrew and walking out of the meeting; his birth name is Chaim Witz, and he was born near Haifa in northern Israel.
 * One story on the website "Overheard Everywhere" has an airport worker in Cologne refer to a pair of female Americans as sluts to one of his fellows -- in German, of course.


 * A woman reported a burglary to the police. Partway in she got a phone call from her father and explained to him, in French, about how she and her boyfriend had set up the fake burglary plot. The investigating officer spoke seven languages, including French. What makes her actions even dumber is that this happened in Canada where even in an English-speaking province one should expect many people, especially police officers, to have some understanding of French. It is after all one of the country's official languages.
 * This anecdote from FML is a perfect example.
 * In Me Talk Pretty One Day, David Sedaris (who is American, but lives in France) writes a hilarious essay about standing on a subway in Paris listening to two American tourists complain about his smell and call him a pickpocket, in English, assuming that he wouldn't understand.
 * These customers were (The Customer is) Not Always Right.
 * A similar entry with customers who insulted an employee in Mandarin without knowing that she spoke the language.
 * Stalin used a translator when talking with Churchill and Roosevelt. Stalin never let on to them that he knew English.
 * When George Takei was a teenager, he earned some extra cash as a seasonal worker among mostly Mexican-Americans. The overseers were Japanese-Americans and one day he overheard them talking in Japanese about how they were going to cheat the workers out of some of their rightful pay. Cue young George telling them in the same language that if they did, he'd report them. They caved.
 * In the end of the 19th century, a French banker visited a Russian factory he owned. There, he saw one man working with a wheelbarrow loaded with material for a blast furnace. He said (in French) "This monkey is working well". However, the worker was actually a nobleman who ran from his house, and knew French perfectly. So, he turned the wheelbarrow at him, and drove him halfway across the yard. When the banker had to climb an ore heap, the man stopped and said (in French!) "sorry, the flooring here is too rough to control the wheelbarrow". The flooring was replaced...