Somebody is startled by another — and screams. The surprise from being screamed at makes the other person scream (usually even louder than the originator), which leads to the first person continuing to scream, which makes the other scream even more.
If more than two people are involved it can end up with a room filled with people screaming in surprise to no end, with no one really knowing why. The Only Sane Man may have to step in and restore order somehow. Rule of Funny prevails—don't expect this to end simply because one or more characters, say, have to take a breath.
- In the Dressrosa arc of One Piece, it even serves as a plot point: When Sugar has Usopp at her mercy, she attempts to kill him by feeding him the ultra-spicy grape that was intended to knock her out, which she mistook for poison. It's so freaking spicy that it causes him to scream his lungs out while making one hell of a Wild Take. The sight of it caused Sugar to scream her own lungs out and faint, this accomplishing the goal that the grape was intended for in the first place, and the entire situation cause everyone present to scream their own lungs out in surprise.
- Yotsuba&!: Yotsuba initiates a three-way scream that goes on for half a chapter; while showing a live frog she caught to her friend Ena, her other friend Miura shows up in an scarecrow outfit, causing Yotsuba to scream. Ena uses the frog to scare Miura, who screams and backs into Yotsuba, who renews her own screaming, and reflexively starts hitting her with Ena's favorite teddy bear, causing Ena to start screaming...
- From Ask Fluffle Puff, the short "Bubbles" has Derpy blowing soap bubbles, one of them popping in Fluffle Puff's eye. She starts screaming in pain, making Derpy scream in turn. It goes on and on until the episode ends.
- Happens in A Very Potter Sequel when Ron pulls out his rat Scabbers, Harry starts screaming, only for Ron to join in.
- In Welcome to Ponyville, if you let DJ Pon-3 sleep with you, your character wakes up screaming from a nightmare. DJ Pon-3 starts screaming as well.
DJ Pon-3: [AAAAAAAAAAAHHHH!]
You: Huh? Why were you screaming?
DJ Pon-3: I don't know, you were doing it, and it looked fun!
- Happens in What Makes Me Scream, the second entry in They Live in a Castle Shorts, after Green Toad reveals that he screams when slapped in the face and Red Toad reveals that he screams when other people scream.
Red Toad: Oh no, there's a fly in your face! [slaps Green Toad]
Green Toad: AAAAAAAAAAAAAAAAAAAAAAAAAAAHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH-
Red Toad: AAAAAAAAAAAAAAAAAAAAAAAAHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH-
- One Night of Insanity has this happen between Bon-Bon, who has just been placed in the room with the withered animatronics, and Foxy. This ultimately alerts the other animatronics, which at that point Foxy shuts up and joins with said animatronics to get Bon-Bon.
- Dragon Ball Z Abridged:
- In Dragon Ball Kai Abridged Episode 1, Vegeta's yell of "It's over nine thousand!" quickly becomes this between him and Nappa.
- In episode 27, Vegeta, Krillin and Gohan start screaming during their fight with Freeza.
Vegeta: Healer's down!
Krillin: Need a res!
Gohan: Out of mana!
(Vegeta starts screaming and they all follow suit)
- In "Cell vs Ken and Ryu", when Ryu loses it and activates his Superpowered Evil Side, he starts screaming. Cell starts screaming as well, and then Ryu tries to perform the Shun Goku Satsu, only for Cell to turn it around and KO Ryu with it. Afterward Cell shouts "What just happened!?"
- In Wings of Rebellion, when Akechi and the Thieves are going through the Haunted House presentation at the Culture Festival, Akira senses one of the students coming after her and rips her mask, making her scream. That scream leads to everbody screaming.
Akira: I'll unmask you![everyone screams]Ryuji: The hell, Akira? What are you doing?!Akira: Uh, sorry!
- Done in Barbie Fairytopia: Mermadia when Elina scares a Sea Butterfly and Bibble ends up screaming with her. Fairy Dandelion even joins in.
- Cloudy with a Chance of Meatballs: "Hair un-balder!" Now, what it does to Flint's dad... anyway, after that, BOTH of them are shown screaming for what is implied to be a long while until Flint's next invention is displayed.
- The page image is from The Emperor's New Groove:
- Used repeatedly in DreamWorks/Aardman's Flushed Away, between pampered house-rat Roddy and the Greek Chorus of sewer slugs.
Roddy: [breathing deeply] All right, Roddy, old man. You can get yourself out of here, and you will. Never forget, The blood of the courageous James Clan flows through your veins.
[He turns to see dozens of slugs staring at him]
- In The Lion King 1½, when Timon and Pumbaa meet for the first time.
[the movie freeze frames on their hilarious screaming faces]
Pumbaa: You know, first impressions are very important.
Timon: Oh, I thought you were a scream.
- Open Season, This is how Boog the bear meets Elliot the mule deer. Boog hears mumbling and turns to see a mule deer tied to the hood of a truck. He sniffs and exclaims "that's nasty" and picks up a stick and pokes the deer with it...and the deer's eye pops open! Boog screams and Elliot screams back and continue to do so for about 10 seconds.
- In Shark Tale with Ernie, Bernie and Oscar. They end up doing it twice in a row.
- How does Woody learn about Bo's broken arm in Toy Story 4? He accidentally pulls it off, causing both of them to scream in fear... only for it to turn out that Bo was just screwing with Woody as her scream quickly devolves into laughter.
- In the original trailer for Clue there's a short instance where Mr. Green is screaming. Col. Mustard slaps him and yells, "WHY ARE YOU SCREAMING!!?" "Because I'm frightened!" "OF WHAT!!?" "Screaming!!"
- In Dr. Dolittle, Dr. Dolittle's daughter Maya sneaks her guinea pig Rodney into the big Calnet meeting. He sneaks away into a bathroom and gets up on a toilet and starts sniffing around the rim, only for a woman that Dolittle treated earlier for a shellfish allergy to come in trying to sneak another snack. She sits down on him. Hearing his squeaking, she sees him and he sees her and they do this (with Rodney going "Aaahh yourself!"). She flushes the toilet and leaves, and he shouts "Somebody get the license plate number! I have just been violated!"
- In Dracula: Dead and Loving It, Renfield is sent into Lucy's room to remove the garlic protecting her. He sees the sleeping girl and lifts up her bedspread to peep at her. Lucy awakens and screams, causing Renfield to emit an even higher pitched scream.
- E.T. the Extra-Terrestrial: When Gertie walks into the bedroom and first sees E.T., the continuous screaming starts — especially funny given the sound of ET's scream and his expression.
- The first day on Hacksaw Ridge, the American unit's cover is blown when a "corpse" sits up and screams, causing the soldier facing him to scream as well. This goes on for a couple of seconds until the first soldier is shot from the back, causing his blood to be blasted onto the other soldier seconds before gunfire kills him too.
- Seen in How the Grinch Stole Christmas! (Jim Carrey version). In fairness to Cindy, the Grinch was just plain scary-looking in that scene, lurking up there in the corner like that.
- Prom Night (2008): Donna opens the door and is startled by Claire who was about to open it from the other side. She screams, which causes Claire to scream.
- In Scary Movie 3, George tells Sue that her teacher Miss Brenda is dead, and then that her dog is dead and that everyone around her is dying, resulting in this.
Sue: My dog's dead?
George: I JUST RAN HIM OVER WITH THE CAR WHEN I DROVE IN! EVERYONE YOU LOVE AROUND YOU IS DYING!
- Happens in Sonic the Hedgehog (2020) when Sonic first meets Tom.
Sonic: Uh... meow?
Tom: [proceeds to tranq Sonic]
- Teenage Mutant Ninja Turtles (1990) had this happen when April wakes up in the Turtles' den and sees them for the first time. She starts screaming and a few of the turtles follow suit.
- In the Underdog movie, when Shoeshine starts talking to Jack, the dog is just as surprised and freaked out as Jack is.
Jack: Did you hear something?
Shoeshine: Nope! Did you?
Jack: Did you just talk?
Shoeshine: Whoa, whoa, whoa! Wait a minute! You can understand me?
- A projective telepath in The Ear, the Eye and the Arm accidentally causes a psionic version of this when he thinks of a train and it scares a baby, whose fear scares him in turn. It's treated seriously, as part of how he's Blessed with Suck: if he hadn't interrupted the reaction in time, they could have both gone insane.
- My Name Is Earl:
- Happens in a flashback where Earl tried to rob a wealthy family only to get trapped in the sons room. Afraid of the boogeyman, the kid looked under his bed only to find Earl. They both start screaming.
- Happens again in another episode, where Earl and Joy are escaping a bounty hunter and decide to hide out at an old trailer in the woods. They discover a homeless man has taken up residence there, prompting this reaction when they find him under the bed covers.
- Done by Mystery Science Theater 3000, with the interesting twist of cutting to a commercial in the middle of it — they're still doing it when we get back, and Tom continues screaming at intervals after everyone else has stopped.
"We'll be right back! AAAAAHHHHH!"
- Occurs rapid fire in an episode of Scrubs when JD attempts to assert authority when dealing with his interns by screaming at Lonnie the intern at the end of a pep talk, only to be terrified by the responding scream from his intern. His interns losing respect for him even averts the trope later in the episode.
- Happens in Seinfeld season 9 episode "The Blood" when Jerry finds out that he was transfused with Kramer's blood. Kramer, initially enthusiastic, starts screaming back in response to Jerry's panic. Later, it happens again, this time with the additional donation and eventual screaming of Newman.
- Done repeatedly in The Sketch Show, in one sketch with a support group for people with phobias - Lee had a fear of screaming, Jim had a fear of apologies, Karen had a fear of repetition and Ronni a fear of awkward silences, while Tim shows up because of a compulsion to bark at people's phobias. It culminates in this:
Lee: Okay, Jim, would you like to tell the group how this problem started?
Jim: Yes, well it all began when I first tried on my grandmother's stockings.
Jim: Sorry. Aagh!
- Done three times at the end of the video for OK Go's version of The Muppet Show theme. First Damian Kulash wakes screaming from discovering it's All Just a Dream. When he discovers he's in bed with the Electric Mayhem, he sceams again, which sets the Electric Mayhem off. Then the same gag is done in reverse, with Dr Teeth waking up to find he's in bed with OK-Go, with the same result. Then Tim Nordwind wakes up to find he's in bed with a bunch of real and Muppet dogs, including Rowlf, and they all just start screaming.
- Happens in Dawn of a New Age: Oldport Blues. Jenna starts to scream upon realising she's naked, causing Vivian to scream as she throws some clothes over, which Jenna responds to with another scream of thanks. Then Crispin wakes up, sees Jenna, starts screaming, causing Vivian to scream again, which startles Crispin and makes him scream some more...
- In Pokémon Sapphire, Whismur's Pokédex entry claims that it can inflict this trope on itself:
"Whismur is very timid. If it starts to cry loudly, it becomes startled by its own crying and cries even harder. When it finally stops crying, the Pokémon goes to sleep, all tired out."
- The opening for Rayman Origins. It starts with Ray realizing he's holding a skull, he screams, and not a second later everyone else does, even said skull.
- Slightly Damned has such a moment between Rhea and Death. Rhea spots Death and starts pointing and screaming. Death responds in turn, partially due to being startled, and partially because no one is supposed to be able to see him.
- In Twilight's First Day part 9, Twilight accidentally stows away on a Royal Guard airship and startles a cadet. When Thunderhead barges onto the scene demanding to know what the racket is about, both Twilight and the cadet scream variously at him, at each other and at how much trouble they're both in.
- One particular sketch of AMV Hell III shows re-dubs a scream from Bleach into a reactive continuous scream, with all the other characters looking on in shock and confusion.
- In Hey Ash, Whatcha Playin'?:
- On Final Fight, Anthony walks in on Ashly and begins to scream, then Ash follows and then their friends walked in and started to scream as well. One of them screamed so hard that his nose started to bleed (which was real and not scripted...).
- Another one has Anthony waking up finding and X on his back and screams once he sees Ash is carrying a knife. Ash also screams while explaining that she's imitating Shadow of the Colossus.
- In episode five of None Piece Usopp falls off a cliff, starts bleeding out of his forehead and screams. Zoro starts screaming and bleeding out of his forehead. Luffy starts screaming and bleeding purple paint out of his forehead.
- The beginning The Nostalgia Critic's review of The Nutcracker in 3D has a rare example where it's done in joy when Critic discovers Rachel Tietz showing up. Malcolm and Tamara join in, and so do a reluctant Walter, Heather, and Aiyanna. When Critic tells the other three who Rachel is, they try again with more enthusiasm, but...
- Tamara: The moment is passed.
- Family Guy: "Into Harmony's Way" has an interesting variation of the two-person scream: Peter and Quagmire get freaked out by a bee and both start screaming, which results in them finding out their voices make great harmony, setting the stage for the episode.
- Gravity Falls: In "The Golf War", Dipper and Mabel open a panel on the windmill at the Royal Discount Putt Hut to encounter the Lilliputtians, tiny people with golf balls for heads. They scream back and forth in shock at each other for a bit, then once both sides have gotten it out of their system one of the Lilliputtians ask "Are we good? We're good?"
- During the bar fight in Korgoth of Barbaria, Korgoth unleashes a brutal series injuries on the Giant Mook who challenges him one on one. All of the other mooks/victims, (virtually all of whom have also already been injured horribly by Korgoth) react by screaming in horror at each bit of brutality. Watch until the end and see for yourself.
- Doctor Rockso from Metalocalypse has one such moment, played entirely for laughs:
Rockso: (whispers) I do cocaine.
- Shows up in the second act of the Mr. Bogus episode "Beach Blanket Bogus", where a woman screams when she sees Bogus in her slushie cup, which also prompts Bogus to scream right back.
- In Phineas and Ferb this happens between Candace and Buford (who's dressed as Little Suzy Johnson) in "One Good Scare Oughta Do It!" as prior to the scene the actual Susie had been torturing Candace.
- Also happens between Candace and a squirrel in the episode "Comet Kermillian", after Little Suzy brings said squirrel out from behind her back, started by Candace due to the Squirrels in My Pants incident.
- In the Regular Show episode "Brain Eraser", when Mordecai walks in on Pops after the latter takes a shower, Mordecai shrieks in shock at the site, prompting Pops to yell right back. This goes on for a while until the two run off. The moment kick starts the plot of the whole episode.
- In the SpongeBob SquarePants episode "Goons on the Moon", Squidward and Rodger Bumpass have this reaction after the former ends up in the studio working on the show while trying to deliver a Krabby Patty to SpongeBob on the moon.
- Teen Titans Go!: In "Parasite", Starfire celebrates one of her holidays, Feast Day, by serving everyone mouthworms. When Robin tries taking a bite of his, the mouthworm starts screaming in shock which prompts Robin to scream right back, ending with him disappearing via smoke bomb.
- In an episode of Total Drama Island, Cody wakes up to Noah sleep-kissing his ear. This results in about three seconds of them screaming at each other.