Someone, usually a child, is wandering in his or her house and walks into two people having sex. (Nobody ever has a room with a lock in fiction.) Most of the time it's the parents. This can be a trigger for A) the parents to give that one discussion we all mention vaguely, B) the resulting Parental Sexuality Squick leaving the unfortunate soul to be shell-shocked for a while, C) being very funny or some combination of the three.
Its psychological term is the Primal Scene, coined by none other than Freud.
Naturally, media always plays this as a traumatic experience, rather than the person just figuring it is natural, quickly realizing it, or just not understanding why mommy and daddy are playing leap-frog naked (and then after looking back on it all, will quickly apply Brain Bleach to forget about it).
And of course, all "child" characters, no matter how old, don't understand sex. Characters identified to the audience as "teenagers" will simply be horrified. This rule applies to almost every example, despite the fact that most children (even 8-9 year olds) will know what they interrupted in Real Life. That said, most offspring are conditioned not to think of their parents in sexual ways, so even if the act itself isn't the big deal, seeing their parents do it can be considered innately disturbing for some.
See Caught with Your Pants Down for the single-player version; for the reverse scenario with parents walking in on their adult child getting frisky, see Parents Walk In at the Worst Time. A subtrope of Interrupted Intimacy.
- This ad for Ragu pasta sauce. It has become one of the more popular ads of 2012.
- A UK ad for Flora butter has two children making breakfast-in-bed for parents on their anniversary and then walking in on the two of them 'wrestling'.
- This Tostitos commercial with the "Mommy and Daddy Wrestling" portrait.
- Seitokai Yakuindomo, for a series running on Vulgar Humour, has a few examples of this.
- Subverted in the resident pure girl Mitsuba, mistook her parents night activity for a wrestling match, which prompted her to seriously train herself in the martial arts despite her dream to become a perfect housewife.
- Aria off-handedly mentioned her mom has been seen "bullying" her dad a lot, while the listeners knew they were having BDSM sex.
- In Berserk, Casca, whose mind was reduced to that of a child due to some unfortunate events, walks in on Luca, her temporary prostitute care-taker, and Jerome, her Love Interest customer.
- In a recent chapter where Casca's healing commences and Schierke and Farnese are in Casca's inner world, they eventually come across the memory of Casca having sex with Guts, and Farnese quickly covers Schierke's eyes so she won't see.
- In Fushigi Yuugi, Suboshi catches his boss Nakago having sex with his dragon and lover, Soi.
- In Happy Yarou Wedding, Yuuhi keeps trying to cover these up as "wrestling" but the five-year-old Shouta doesn't entirely buy it.
"Why do you need to take your pants off every time?"
- In one of the databooks for Love Hina, it reveals Motoko's fear of turtles is derived from walking in on Tsuruko and her husband.
- For those that don't understand, this fear is based off Japanese wordplay: The kanji for "turtle" and "head of the penis" are the same.
- In the manga Ooku, the young Tsunayoshi has a breakdown after discovering her father having sex with her best friend.
- In Revolutionary Girl Utena, Nanami comes across Akio and his sister, Anthy, resulting in reaction B.
- In Yosuga no Sora: During Sora's arc, Kozue and Nao walk in on Haruka and Sora during climax; Kozue's reaction is to run away screaming hysterically. During Nao's arc, Sora walks in on Haruka and Nao going at it; she kicks Nao out of the house.
- And in the Back Story of both arcs, Sora secretly sees Nao forcing herself on Haruka.
- Murciélago has Hinako walking in on Kuroko having sex with one of her lovers. Hinako seems to only be slightly unnerved by it and it's implied that this isn't the first time that this has happened.
- A non-comedic version of this happens in Neon Genesis Evangelion, where during Instrumentality, Misato relives a moment of passion between herself and Kaji - except this vision is being shared by Shinji as well, despite Misato's begging for him not to see her state of weakness.
- Sand Chronicles has a painful Played for Drama instance, when a very young Fuji in a flashback walked in on his mother with another man. It's what kicked off their aloof relationship, and Fuji's bitter about his place in the family while being certain that the man is his father. However the man turns out to be Shiika's instead.
- Invoked in Cool-Kyou Shinsha's Mononoke Sharing when Youko starts having sex to hide the fact that she was actually asking someone about getting a birthday present.
- In Watchmen, a young Walter Kovacs walks in on his prostitute mother servicing a client. Unlike most instances of this trope, this is not Played for Laughs and is shown to be very Harmful to Minors, the behavior of the adults involved plays a part too.
- In Runaways, when Gert finds out her parents are actually super villains, she says "This is worse than the time I walked in on them doing it!"
- Robert Crumb once tried to explain such a scene to his son as him and Aline (his wife) playing horse-riding. He didn't find an explanation though for why Aline had to be naked to do this.
- In Kick-Ass, Dave walks in on his father and his new girlfriend doing it doggy-style on the living room couch.
- At one point in Scott Pilgrim, the titular character walks in on his gay roommate having sex with a guy. He's horrified.
Wallace Wells: Presumably, you saw his junk, and I apologize for that.
- In Friday The13th Pamelas Tale issue two, in June of 1957 Jason Voorhees is enraged by the sight of Barry and Claudette having sex. That probably led him to kill everybody who engages in nonmarital sex.
- Red Ears: One gag has a child witnessing his mother and father having sex, and later asking them what they were doing. Since he's still too young for The Talk, the mother explains that she was sitting on the father to make his belly flatter. The child then says that wouldn't help anyway, since their female neighbor comes over when the mother isn't home to blow it up again.
- In Sex Criminals, Robert the gynaecologist's somewhat conflicted attitudes to sex come from, as a young boy, catching his parents not merely having sex but engaging in some fairly heavy-duty BDSM, with his father bottoming. (Literally).
- Happens in this Naruto fanfic, with the predictable result/s.
- In the (not for faint-hearted!) Pokémon fic Latias' Journey, the cast enjoys a quiet-before-the-storm party on the night before the final battle. Some of them go for more... involved celebrations than others. So anyway, Phanpy walks in on Uncle Brother Pikachu going at it with a Weavile. Traumatized, he runs to Aunt Corsola for help, and walks in on her right in the middle of Crawdaunt's massive orgy. You can probably imagine what happens next.
- In the Order of the Stick fic the Oneiroi Series, Vaarsuvius's parents intentionally have sex where their child can see them, leading to this situation often. On the other end, Tiasal has walked in on her (more modest) parents an unnamed amount of times and has even seen her grandparents going at it, and she's demonstrated a surprising amount of nonchalance about the whole thing.
- Due to a series of spoileriffic circumstances in Luminosity, Elspeth ends up with almost all of her father's memories. After a person asks a question about how much she can remember, she thinks of the wrong memory, and...
I remember my parent's honeymoon!
- Played With in a recent chapter of this fanfic— Kyon's sister walks in on him and his girlfriend having sex. Evidently this happens so often that it no longer fazes her. Also, Mikuru (who in this fic is Kyon and Haruhi's future kid) knows about it, and is a bit shocked, even though she knew it had to happen eventually.
- Toyed with in the My Little Pony: Friendship Is Magic fanfic Progress. Princess Luna's embarrassed enough to flee to a castle labyrinth and blush bright red after walking in on her roommate and roommate's boyfriend, but as she's old enough to figure prominently in the local Creation Myth and more than old enough to be aware of sex (if only in the theoretical sense), she attributes this reaction to her old-fashioned views. Then she has a particularly surreal nightmare about walking in on Celestia with Luna's abacus, suggesting the matter to be much more traumatic than Luna is willing to admit to herself.
- In chapter 4 of the My Life as a Teenage Robot fic My Life as a Teenaged Von Neumann Device, Sheldon freaks out when he walks in on Jenny and Brad after they've just had sex... with unfortunate consequences, as Sheldon ends up running into the street and getting hit by a car, forcing Mrs. Wakeman to upload his brain into the body of the Silver Shell.
- In this Avatar: The Last Airbender fanfic, Kya walks in on disrobed parents Aang and Katara in the process of foreplay. While she immediately understands whats going on, shes still horrified.
"Mom, Bumi won't stop mak," Kya froze mid-rant, her irate complaint dangling mid-sentence as she fully assimilated the sight of her parents in bed and tangled in one another's arms. In that brief, appalling second, it was difficult to determine who was more horrified, Aang and Katara or their traumatized teenage daughter. However, Kya's explosive reaction that followed mere beats later firmly determined that it was the latter.She immediately clapped her hands over her face and bolted down the hallway screaming. "Oh my, blech... my eyes! My EYES! Dad, you said you were going to read a book! What's wrong with you people? I'm blind! The oogies!
- Worst possible variation in Reprise, the prequel to Hivefled; among other horrific things, Gamzee is forced to watch his potential future siblings be made. Would be bad enough if they weren't also getting across the point that he's a "moirail bastard".
- Played with in this NSFW My Little Pony: Friendship is Magic fic. Twilight follows Pony!Flash Sentry after he tells her he's seeing someone else. Hilarity Ensues. She sees him and Shining Armor have sex, and is disgusted because she thinks Shining is cheating on Cadence. But then it is revealed that he wasn't, as Cadance lets him do that, and likes to watch.
- In the My Little Pony: Friendship Is Magic fanfic Crashback, Twilight Sparkle inadvertently witnesses her own conception, courtesy of a flashback potion.
- The Monsters University fanfic Born to Please has Chet walking in on two of his fraternity brothers having sexual relations.
- Ai Yori Aoshi Koi: Chika inadvertently discovers Kaoru and Aoi's Secret Relationship when she walks in on them during an intimate moment in the bathroom.
- Meg's Family had a scene where Maddie, mistaking a moan from her parents' room for a sign of trouble, grabs her BB gun to help. It then cuts to Brian finding the poor girl clutching her gun, rambling about how the bullets won't work.
- In its predecessor, Meg's Boyfriend, Stewie walks in on Meg and Zack having sex. Predictably, he didn't take it well, and the next chapter notes that he may have been scarred for life.
- In the Naruto fanfic From Pride to Shame, Bolt Uzumaki hides in a closet to prank this father due to his frustration for his parents' divorce and being stuck in his father's shadow. He ends up watching his father have sex with his ANBU captain, Sasuke in his office.
- In the remake of Battle Fantasia Project Minako mentions that her hate for tentacle monsters stems from walking on her mother having sex with one on her own bed and her father doing the same on Minako's, courtesy of Jadeite's last energy-draining scheme.
- It happens in the eighth episode of The Second Try: Aki cant sleep at night so she gets out of her bed, goes to her parents room and opens the door right when theyre making love. Thankfully she was only three at the most, so she had no idea what they were doing. Her appearance panicked her parents anyway.
- In Chapter 3 of Son of the Sannin, Shizune walks into Tsunade's room, right when she and Jiraiya have woken up and are in the middle of getting dressed in a hurry. The next morning, she finds Tsunade's room unusually clean and neat, and then goes downstairs to the living room...
Shizune: OH DEAR KAMI! THAT'S THE ONLY COUCH WE HAVE!
- In How the Light Gets In, Thea walks in on Dean and Laurel, right when he's about to go down on her. They aren't actually her parents, but they are Parental Substitutes, so it counts. When Dean asks why didn't she knock, she asks why didn't he lock the door. Sara arrives a few seconds later, and after lightly teasing Thea about it, starts to talk about the time she walked in on her parents having sex.
- Prince Joffrey Baratheon is made aware of his true parentage when he accidentally walks into Cersei and Jaime in Purple Days. Cersei... doesn't help. At all.
- Ash mentions this having happened with him in Shudo cross Modern Ash: The Professor Who Observes his Charges, specifically during the equivalent of Pokémon S3E39 "Forest Grumps". So it was less walking in on his mother with someone as one might assume, and more Ash was stuck in a forest with mating bipedal bears with anger issues who shoot laser beams at the drop of the hat. He refers to the experience as mentally scaring.
- In the sequel to the above Shudo Cross, unlike Ash, Verity had this happen with her moms without mental scaring. In her own words they were careful to not treat it as traumatizing to avoid negative connotations forming in her mind, akin to the passage from the Sex Positive Home in the quote section of this page.
- Downplayed in the Batman fanfic "Melody for a Mockingbird;" Damian/Robin only walks in on Bruce and Selina, Bruce's fiancée, in a pre-foreplay make out session, but because of Selina's growing status as Damian's mother figure, Parental Sexuality Squick kicks in and the sight is enough to send him screaming out of the Batcave. Alfred later finds the preteen curled up in a Troubled Fetal Position.
Damian: Father and Selina...tongues...it...revolting!
- A very dark version occurs in Orphan, when Esther catches Kate and John having sex over the kitchen counter.
- Averted in Poltergeist, as Carol Ann's request for a late-night glass of water takes place when her parents are only engaged in foreplay, not intercourse.
- In Rain Man, Raymond walks in on Charlie and Suzanna making love, and as he doesn't understand what's going on, mimics their orgasmic moans until Charlie realizes he's in the room and snaps angrily at him.
- In Reality Bites, one of the characters tells that this once happened to her.
- Occurs in The Rebound when Sandy's young son walks in on her and Aram having sex on the living room couch. Hilarity Ensues. Not much mental scarring though.
- Twice in Enter the Void we see a flashback of Oscar as a kid as he walks into his parents in their bedroom having sex.
- In Whip It, Bliss "Babe Ruthless" Cavendar invokes this to induce vomiting in her very, very drunk best friend, Pash.
- Body Heat. The adulterous Matty is about to perform fellatio on her lover when her husband's niece walks in on them.
- 3000 Miles to Graceland: Jesse goes into the bedroom as his mom is noisily having sex with Michael, going on to his business without concern, indicating it isn't the first time he's seen this.
- Alluded to in Dennis the Menace, where the protagonist tells Mr. Wilson that his parents "wrestle" on weekends. Clearly, he's never figured it out.
- In Stepmom, the already tense relationship between Jackie (the ex-wife) and Isabella (the titular character) gets even worse after Isabella sheepishly admits that daughter Anna walked in on her and Luke (the father) having a Shower of Love.
- In The Da Vinci Code, a version of this is the reason why the female protagonist had a falling-out with her grandfather. As a young girl, she walked in on him performing a sexual ritual. Langdon explains that her grandfather was part of a group that followed ancient pagan rites and believed that sex was the way to achieve enlightenment.
- In Memory, Miles has a moment of surprise when he realizes his Aunt Alys (widowed since shortly before Miles's birth) has started sleeping with his former boss, ex-Spymaster Simon Illyan. When Alys's son Ivan finds out, he has reaction B, and the reader gets a nice dose of reaction C from the interplay. Unlike most instances of this trope, Miles and Ivan are adults. Ivan's reaction has more to do with: a) the fact that this is his mother we're talking about, and b) the fact that both Simon and Alys have public reputations for being extremely prim and proper (well, for Simon it's more "respectable" than "prim"), and what they're doing together is... not.
- Robin in The Tomorrow Series mentions this was how she last saw her parents.
- Briefly discussed in Head Count by Ingrid Noll: when Maya is in counseling after accidentally killing her brother, she makes up a dream about being a little bird that flies around and looks into people's windows. Her psychiatrist assumes that she must have walked in on her parents as a child.
- Norman Mailer's The Castle in the Forest has none less than a young Adolf Hitler being traumatized after walking in on his parents having sex in the 69 position.
- Parodied in the Girl Genius novel Agatha H. and the Airship City: Young Agatha was traumatized by walking in on her "construct" foster parents recharging themselves.
- Seemingly an isolated incident in J.R. Lowell's 1972 thriller Daughter of Darkness. Willie Connolly knows what sex is, that's not the problem; it's the idea of her beloved parents going at it like animals. Yicch!
- In A Song of Ice and Fire, one of the key events that sets the plot in motion in the first book, A Game of Thrones, is 7-year old Bran Stark climbing a castle tower and accidentally witnessing, through a window, the Queen having sex with her brother.
- Legacy of the Dragokin: Daniar and Kalak express their love for each other right in front of Benji.
- This is one of the catalysts to the big deception in Atonement. Briony encounters her older sister Cecilia having sex with her lover Robbie in the library. The two awkwardly leave the site upon discovery. Briony has already had her suspicions about Robbie due to several previous events that tell her Robbie is sexually abusing her sister, when in fact all the instances were consensual. Their discovery here is thus the final nail to the coffin that causes Briony to pin Robbie for revenge.
- In To Sir, with Love, teacher Thackeray notices that something has happened to upset one of his students. When he speaks with the girl's mother, she sheepishly admits that the girl walked in on her and her boyfriend. (The girl adored her deceased father and is unhappy that her mother is embarking on a new relationship.)
- One rather central to the plot occurs in We Can't Rewind. While the parents actually did think to lock the door to their cabin, they forgot about the bathroom access running between their children's cabin and their own.
- Breaking Bad: Walter Jr. comes home during (or possibly after) his parents had sex, asking where they are. When he realizes that they are both in the bedroom, claiming that they are "busy," he gets the message and walks away from their room in disgust.
- A 1973 episode of The New Dick Van Dyke Show had this. When CBS refused to air it, writer-director Carl Reiner quit the series in protest.
- The formerly name of "Oh Kitty" was for the scene in That '70s Show in which this happens to Eric. Donna reveals that it also happened to her when she was a kid - which she can recall vividly even a decade or so later.
Kitty: Oh! Oh Red!
Red: Oh Kitty!
Kitty: OH! MY! GOD!
- Used more than once too, as later in the series, Eric casually walks into the kitchen, where his parents are playing an "adult" version of Marco Polo (don't ask).
- Inverted in an episode when everyone walks in on Eric and Donna going at it on the kitchen table. Red and Kitty later are seen scrubbing the table with a mixture of bleach and lighter fluid, then deciding that they need a new table.
Hyde: Alright! Donnas butt!
Red: Dammit! I eat dinner on that table!
- In an episode of Sex and the City, Brady sees Harry and Charlotte having sex. Charlotte freaks out and calls Miranda, panicking and convinced that she has damaged the boy for life. Miranda is amused and explains to Charlotte that being a toddler, he doesn't even know where his nose is, let alone what sex is.
- J.D. explains his emotional problems in Scrubs:
My emotional journey began at 5 years old when I walked in on my parents having sex in a position my father would later playfully describe as "the jackhammer."
- An episode of Seinfeld had George, as well as his cousin, Jerry, and their friend Frankie walk in on George's parents having sex in Jerry's van. The Stinger showed George's father giving him The Talk before getting up and announcing that they were going to do it again while George puts his head on the table while groaning "Make it stop..."
- On Desperate Housewives, Gaby and Carlos are having blind sex (he is blind; she's wearing a blindfold). Gaby hears a sound, rips off the blindfold and, lo and behold, there is Juanita drinking from a juice box. They don't know how long Juanita has been there, either.
- Dawson from Dawson's Creek was constantly walking in on his parents having sex, at least in the first season. He also once saw the "preview" to some reconciliation sex between them, but managed to sneak out unnoticed before "the main attraction."
- Monica from Friends first found a video tape of her parents having sex (complete with "Oh Jack" and "Oh Judy"). Then a few episodes later she was hiding from her parents in the bathroom when both walk in, and, well, this quote pretty much sums it up:
Ross: Mon? Mon, are you okay?
Monica: Remember that video I found of Mom and Dad?
Monica: Well I just caught the live show.
- In a later episode, when she recounts this, Chandler mentions that he once walked in on his parents and a man having a threesome.
- The Drew Carey Show. His response to a psychiatrist:
- "Why is Daddy hurting Mommy? Wait, he's not hurting Mommy, he's loving Mommy."
- Then there's the time he walked in on his brother and Mimi having sex. He had his kitchen bricked off and his couch sent out to be exorcised.
- In an episode of Oliver Beene, Oliver walked in on his parents doing the deed, but they placated him by claiming to have been playing some sort of game. The narration notes:
Years later, I realized I had walked in on my parents having sex, and was appropriately disgusted. Back then, I was just glad they'd managed to make up so we could be a family again.
- In The Fresh Prince of Bel-Air, Will walks in to his mother's room, and finds her in bed with his fiancee's father. For extra shock points, this was on the day before the wedding. Amusingly, after first meeting one another, they nearly came to blows.
- In Six Feet Under, Nate's daughter Maya sees him and Brenda having sex and starts jumping up and down.
- In the first episode of Titus, a misunderstood message causes Erin to walk in on her parents.
Titus: Your dad isn't dead.
Erin: Yeah, I know. Otherwise, what I walked in on my mother doing to him would've been so sick!
- An episode of Ready or Not revolved around sexuality, beginning with Amanda walking into her parents shagging it out.
- Torchwood has the adult version when Gwen walks in on Jack and Ianto. In a hothouse. Hilarity Ensues.
- Pictured above: On Modern Family, Phil and Claire's kids walk in on them having sex which traumatizes both Claire and the kids, while Phil tries to deal with it humorously. Afterwards, the kids cope pretty straightforwardly with what they saw, but are horrified all over again on realizing that their parents will insist on talking about it. The kids buy a lock for the bedroom door so it never happens again... but The Stinger reveals that the rather loud noise of the lock quickly becomes a horrible Pavlovian trigger.
- The King of Queens Doug and Carrie look after Deacon and Kelly's kids at their apartment while they're out of town. One of the kids walk in on Doug and Carrie having sex and draws a picture of it.
- In Sugar Rush, Kim finds out about her mother's affair with their home decorator when she walks in on them having very loud sex in the living room.
- Referenced in this scene from Eastbound & Down.
- In 30 Rock Nancy Donovan has given at least two different excuses to her children when they walked in on her. She comments to Jack that they walk in a lot, but doesn't specify how much "a lot" is.
- In Mad Men, Sally Draper sees her step-grandmother giving a blowjob to her Honorary Uncle Roger Sterling. Given that she's pretty precocious (despite being only 12 or 13, she's more aware than the average girl her age, and has been masturbating herself for at least a year), she doesn't seem to be particularly scarred—merely astonished and kinda disgusted.
- Much earlier, Sally and her little brother Bobby also walked in on their parents having sex once, which Don and Betty awkwardly explained as "Mommy and Daddy are... sleeping..." When Sally later sees a picture of Paul Kinsey's girlfriend, she asks him "Do you kiss her? Do you lay on top of her?"
- Later, however, Sally walks in on her father having sex with the upstairs neighbor. While not necessarily disturbed by the act itself, she is appropriately outraged and disappointed that he would cheat on Megan like that.
- In Single Father, six-year-old Evie walks in on her recently widowed father in bed with her dead mom's best friend. While Evie doesn't tell anyone and probably doesn't actually understand what happened, she does say that her dad and Sarah "really like hugs" with a look that says she probably at least knows that they were doing something inappropriate.
- On Once Upon a Time Emma Swan and her son Henry walk in on Snow and Charming in bed. Henry is only eleven and is oblivious, asking why they're sleeping in the afternoon. Emma is scarred for life because while they are about the same age because of a magic curse, they're still her parents. Said parents seem amused by the incident, probably because they weren't actually "busy" when their daughter and grandson walked in, just in bed.
- They had just finished being "busy", and were clearly post-coital, with a Modesty Bedsheet, so it was pretty close.
- And it's their fault for putting their marital bed in the same room as the kitchen and front door.
- In the Misfits episode where Curtis nearly starts a Zombie Apocalypse, Rudy reveals that he is afraid of cheerleaders because, when he walked in on his parents having sex, his mother was dressed as a cheerleader.
- One Psych episode involves Shawn (and his mom) moving back in with his dad to help Henry recover after being shot. At one point, Shawn walks in on his divorced parents having sex. The scene then cuts to him curled up in bed like a traumatized child would after witnessing such a thing. His father also tries to have what sounds suspiciously like "the talk" with Shawn.
- This is how Viva, the main character of Some Girls discovered her father's relationship with her new gym teacher: she walked in to see Anna riding Rob in the living room and immediately shuts the door in disgust. Luckily for Viva, both Anna and Rob were clothed but poor Viva still can't stand Anna.
- In the second-season premiere of The Americans, poor Paige walks in on her parents performing mutual oral sex on each other.
- Discussed in the Veronica Mars episode "The Wrath of Con"; while playing "I Never", Duncan asks if any of them have seen their parents having sex. Lily drinks, and describes how she walked into her parents' room to borrow her mother's sweater and saw her parents. Interestingly enough, Duncan is more freaked out about this than Lily was.
- On The Big Bang Theory, Sheldon pays a surprise visit to his mother. He glances through the front window and sees, as he puts it, "Mommy with a naked man and trying to be a mommy again."
- When he was thirteen, Sheldon walked in on his father cheating with another woman. Neither of them ever brought it up. (It also explains why he always knocks three times: the second and third knocks gives time to put one's pants back on.)
- After spending the night together, Olivia and Fitz are startled the next morning when Cyrus storms into Liv's bedroom and shouts "GET UP!"
- At OPA, Harrison and Abby find their fellow Gladiators Huck and Quinn "incesting all over the office".
- Karen, Fitz and Mellie's teenage daughter, flees a room in the White House residence after walking in to find her mother "on [her] knees with 'Uncle' Andrew" (Fitz's good friend and running mate).
- To add to Mellie's further humiliation, she runs after her angry and traumatized daughter half-dressed, only to encounter a shocked Olivia (whom she often calls "whore"), who was walking past said room at the time and witnessed everything.
- One The Whitest Kids U' Know sketch has this having happened as the premise ("This is why knocking is so important"). The dad's attempts to do The Talk with his daughter are complicated by the fact that she didn't walk in on him having sex with her mother... she walked in on him having sex with a donkey.
- In Life in Pieces, Matt walks in on his parents having sex on their couch. Later they decide to go to a more private location...which is above his bedroom in the garage, and he can hear them through the very thin floor.
- In an episode of Family Matters, after Laura and Steve can't look at each other when Laura walks in on Steve in the shower (this was after Steve moved in with the Winslows), Eddie puts things into perspective for them as he tells them about how he walked in on Harriet and Carl when he was a kid, and while it did horrify him, he did manage to move on.
- On Soul Food, Kenny and Maxine go at in the kitchen. Just as they're climaxing, they look up to see their son watching them, frozen in horror.
- One of the most notorious and controversial examples in British TV history was in The Singing Detective, when the protagonist Philip Marlow, as a boy, catches his mother having adulterous sex in a forest. The experience is implied to leave him with permanent psychological damage.
- In a scene which seems potentially inspired by The Singing Detective, Vanessa Ives' psychological and spiritual problems in Penny Dreadful begin when, as a young girl, she catches her mother having adulterous sex with their next door neighbour, the father of Vanessa's best friend, in the garden.
- A milder version on Different Strokes, when Arnold encounters Philip's current girlfriend in the hallway. Despite his young age, he realizes exactly what's going on, given the early morning hour and the fact that she's only wearing a nightgown.
- Another mild version on Frasier when Frasier asks Martin how his date went, only to have the woman in question walk into the room, thus revealing that she spent the night.
- Sisters. Two of the girls walk in on their mother and her companion Truman basking in the afterglow.
- NCIS Tony walks in on his father and his neighbor in his bed, once again resetting the clock on their attempts at reconciliation. (For added Squick, years later, viewers learn there was a friggin CORPSE under the floorboards under the bed).
- Kana from Kana: Little Sister once catches her brother Taka and his friend Yumi having sex. Aaaaaawkward.
- A dramatic variant in The Last Birdling, when one of the child protagonists, Tayo, walks in on her mother being raped. The player then gets a choice between killing the man or just scaring him off.
- A funny machinima made with The Sims 3 milks this trope for all it's worth.
- In Psychonauts, it is revealed that as a kid, government agent Sasha Nein read his father's thoughts to see what his Missing Mom was like. It doesn't end well.
- A pretty tragic example, seeing as he was just remembering the woman he loved and it causes Sasha to freak out so badly he runs away from home.
- You Don't Know Jack: The Ride includes a question, based on the idea that Steven Seagal movies all have three syllables (Under Siege, Hard to Kill, et. al.) and asks the contestant(s) to identify the likely plot to a Seagal movie named Primal Scene (the correct answer, of course, being the outline of this trope). At the end of the round, players are treated to someone impersonating Seagal's voice and acting style and blandly exclaiming, "Oh no, mom and dad are wrestling!"
- A variant (photographs taken at the time by a third party, seen after the event) occurs in Meet The Spy... Sort of. It's probably quicker to watch than to try and explain.
- Dramatic variant in the backstories of Long Live the Queen The child in question happened to see his father having sex... with his half-brother. And when she found out, his mother murdered his father. Said child grows up rather traumatised.
- Having no ability to control his psychic powers, Psycho Mantis of Metal Gear Solid was forced to view countless people's sexual fantasies, leaving him very badly warped.
- South Park
- In South Park: The Stick of Truth, when the player is shrunk by the Underpants Gnomes, he chases them down to his parents' bedroom just as they're having sex and culminates to a boss battle right under them as they're doing the deed. You get an achievement if you simply stay and watch them for an entire minute.
- In South Park: The Fractured but Whole, this is part of the New Kid's in-universe superhero backstory; the sight of catching the man he trusted fucking the woman he loved caused him to devote his life to fighting crime. Near the end, you actually travel back to this point in time, where you can stop your parents having sex. However, The Stinger shows them going to the bedroom to have some private time, which Professor Chaos uses to convince them to become a bad guy.
- It happens (NSFW) in Sexy Losers (the strip is even titled "Primal Scene"), and being SL, it wasn't your garden-variety sex either...
- This strip◊ from the Magical Girl Lyrical Nanoha Strike Out Fan Web Comic by Entropy Max.
- Happened to Faye from Questionable Content.
- Marten is apparently fine with his professional dominatrix mother describing her sessions with clients. But if she's talking about his dad...
- Note that Dora's remark in the last panel indicates she's had this experience, too.
- Marten is apparently fine with his professional dominatrix mother describing her sessions with clients. But if she's talking about his dad...
- In Niels, Kiddo walks in on this.
- An early Kevin & Kell had Rudy walking in on the two titular characters doing some roleplaying.
- Nip and Tuck: Tuck goes to visit his parents at a rather, inopportune moment: "My eyes are burning...". And it seems that his brother had a similar experience years earlier.
- Seems to have happened off-strip, but little Scarlett from +EV knows about the game that only mommies and daddies can play. See here.
- In It's Walky! Ruth gets the surprise of her life when runs home in an emergency only to find her father the doctor (who always told her to "act with integrity") screwing the mother of the little girl she was babysitting.
- El Goonish Shive implies that Broken Bird Susan's various issues stem from when she was traumatized as a little girl by accidentally walking in on her father and a woman who was not her mother, though the true psychological damage probably occurred when he asked her to lie about it. It certainly didn't help matters that Susan was then raised solely by her mother, who seems to have lost all faith in men as a result of the affair.
- Rachel is shocked when she walks in on her mum and dad in this Ladies In Waiting strip, but only by how bad they are leapfrog.
- In the flash film Nin10Doh! by 'Kirbopher', Ness walks past a porno theater. Being psychic, he is reduced to a quivering wreck on his bed.
Ness: Everything... I could hear... everything... they were thinking!
Poo: Oh, the poor child.
- Made even funnier if you recall Itoi's explanation for Giygas: when he was a child, he walked in on a movie sex scene that ended in murder, mistook it for a rape scene, and when he reached adulthood, he channeled his childhood shock and terror into Giygas.
- "I WARNED YOU CHILD!!!"
- Invoked in the American Dad! episode "I Am the Walrus"; Steve is trying to usurp Stan's role as the Alpha Male of the house, so Stan tricks Steve into walking in on him and Francine being intimate, since only the Alpha has the right to mate. After Not What It Looks Like, he tells Steve that the fact that he mates and Steve doesn't proves he's still top dog. Then he chases Steve out of the room while yelping like a Walrus.
- Family Guy has quite a few examples.
Lois: Now, you shouldn't be frightened, Stewie. What you saw was actually a very beautiful thing.
- In "The Son Also Draws":
Stewie: Evidently, madam, you and I differ greatly in our conception of beauty.
- There also the episode focusing on Lois's brother, Patrick, who as a child saw his mom having sex with Jackie Gleason. As a result, he went crazy, was shipped off to a mental hospital (at a young age no less), and developed a pathological hatred for obese people. So much so he goes on a murder spree when Lois temporarily releases him (of course, Peter's idiocy is also to blame).
Jackie Gleason: Pow! Right in the kisser!
- A variant is the one where Peter & Lois decide to have sex in his office.
Peter: Opie's right there.
Lois: I want him to look, Peter. (Opie runs away in terror)
- One episode has Peter and Lois going at it, while showing Chris and Meg cowering in their own beds, just wanting it to be over. They've been through it enough to know what's going on. Stewie is already asleep, and is dreaming that Peter and Lois are lumberjacks taking turns at chopping down a tree. When Peter finishes up, he asks if he did good, and Lois half-heartedly says he does. We then see her pull out a chainsaw to finish chopping down the tree while a slow vibrating sound is heard.
- King of the Hill had Hank walking in on his elderly mother and her new boyfriend having sex on his dinner table. He goes temporarily blind as a result.
- The Simpsons had a Flash Back to Bart's first words. He's walking down the hall and sees Homer and Marge fooling around, to which he says "¡AY CARAMBA!"note For obvious reasons, Marge thought it better not to bring it up.
- In another episode, Bart walks in on his parents again, worried about having seen a UFO - he doesn't figure out what they were doing, but both Homer and Marge scream "Don't turn on the light!" in panic as they cover themselves with the pillows.
- Also happens in "The Haw-Hawed Couple," when Bart and Lisa walked in on Homer and Marge 'Snuggling', despite the boombox playing the fake argument tape Homer and Marge made, leaving Bart traumatized.
- Until he gets some perspective from Milhouse: "Trust me, Bart, it's better to walk in on both your parents instead of just one of them."
- There were quite a few times when Cartman of South Park is exposed to his mother's oft-mentioned promiscuity, though usually through seemingly blank video tapes.
- The most memorable example came from The Movie, when the boys are on the internet and stumble on a German porno.
Kyle: Dude, it's a lady getting pooed on!
Stan: Whoa, is it Cartman's mom?
Cartman: Oh, very funny!
Kyle: Hey, it IS Cartman's mom!
- Played with in "Insecurity"; the plot kicks off when Ike walks in on his parents role-playing and incorrectly believes that his mother is having an affair with the UPS man. Word of this spreads so that soon the other men in town are convinced he's after all their wives.
- In the episode "Wieners Out", Kyle and Ike walk in on their parents engaging in golden showers. Poor kids are going to need a lot of therapy after that...
- The most memorable example came from The Movie, when the boys are on the internet and stumble on a German porno.
- In Bob's Burgers, Gene and Louise interrupt their parents' "sexy bath", but don't seem to be disturbed or upset, and are more concerned as to how they're gonna pee.
- The Oblongs:
- Biff and Chip walk in on their parents having sex and scream in horror. Then, much later in the episode their mother mentions that she hopes the boys aren't too traumatized. Cut to Biff and Chip, still in the shower literally scrubbing their eyes with soap screaming that they can still see them.
- On the flipside is Milo, whose room is right next to his parents', who can't sleep at all without the sound of his parents' lovemaking to act as white noise. When Bob gets his genitals stepped on in an accident, the following two weeks of healing result in Milo not getting any sleep at all.
- In F is for Family, after Billy witnesses his parents having a heated argument, he also hears them starting to have sex, and even sees their posteriors, WHILE HIDING UNDER THE BED, AND FEELING THEIR LOVE-MAKING ON TOP OF HIM! Later at dinner, when they start acting playful, he promptly barfs on cue.
- In Metalocalypse, Skwisgaar walks in on his mother having a threeway. Twice. The first time he was at most on the young side of teenager.