Killer Klowns from Outer Space is a 1988 Sci-Fi Horror Comedy film created by the Chiodo brothers, a team of creature effects designers and animators. It is the only film they wrote or directed.

A spaceship shaped like a giant circus tent lands on the outskirts of a small town. The occupants are aliens that look like Monster Clowns. They begin abducting the townsfolk, sealing them in cotton candy cocoons, and then draining them of their blood. Only one man, his two delinquent friends, his girlfriend, and her cop ex-boyfriend can stop them.

A very Affectionate Parody of 1950s B Movies (particularly The Blob) with just about every alien invasion and circus trope present.

Made on a $2 million production budget, the movie bombed at the box office most likely due to a lack of marketing and being passed on by major theater chains in favor of big studio films when first released. Over the years the film became a cult classic and made more revenue off merchandising such as action figures, Halloween costumes and T-shirts.

In spite of director Stephen Chiodo's best efforts, no sequel or television series has emerged. Syfy attempted to make a movie for their channel but couldn't purchase the rights, then in 2020 a story spread about 20th Century Fox silently buying the rights to make a theatrical movie but then Disney aborting the project after the acquisition of Fox. This was assumed to be the end of the line, until in March 2022 MGM turned out to be still holding the rights to the film (which they bought as part of the Epic library in the late 90s) and with the announcement of Amazon purchasing their library, there could be a new chance for the Klowns to return, which remains to be seen as its Development Hell state continues.

Killer Klowns has also earned its own scare zone at Universal Studios Orlando's Halloween Horror Nights event in 2018. It later returned to the event in 2019 and 2022 as a haunted house.

During the Gamescom 2022 opening night, it was revealed that an Asymmetric Multiplayer video game of the film was being made: Killer Klowns From Outer Space The Game. Co-developed by Teravision Games and IllFonic (known for Friday the 13th: The Game among others), the game was released on June 4th, 2024, with early access for anyone who pre-ordered it starting one week earlier, on May 28th. Watch the trailer here.

KILLER TROPES FROM OUTER SPACE:

• Achilles' Heel: Destroying a Klown's nose kills them instantly.
• Acid Attack: The Klowns toss a barrage of pies onto a security guard. Said pies melted the guard till he was nothing but bones.
• Advertised Extra: A Klown, whose name is Magori, has his face shown on one of the DVD covers, yet he appears for only a few seconds.
• Aerith and Bob: The Klowns all have interesting names like Jumbo, Shorty, and Storefront... and then there’s ones simply named Joe, Danny, and Frank.
• Affectionate Parody: Of 1950s B-Movies.
• Afraid of Clowns: In a deleted scene, Debbie has a bad experience with clowns as a child when her family took her to the circus. That made Debbie afraid of clowns ever since.
• Agent Scully: Officer Dave begins in this role because the whole thing about the Klowns is too impossible to believe (even assuming the giant hole left behind where their ship landed is a prank) but he remains a Reasonable Authority Figure by investigating when his ex-girlfriend asked him to and he accepts Klowns exist when he sees them in action. Officer Mooney remains a truly unsympathetic example of one all the way to his brutal demise because he does not believes it and furthermore develops the utterly insane alternate theory that the Klowns' attack is somehow a scam performed by the entire town to drive him nuts, even when Jumbo enters the police station in search of more victims.
• Alien Invasion: The Klowns have come to Earth to suck Earthling blood for food and also to kill people for fun.
• Aliens Are Bastards: The Klowns are highly sadistic, beyond Blue-and-Orange Morality.
• Aliens Speaking English: The Klowns mostly speak their own language, but there are a few scenes where they speak English by mimicking others voices. For instance, one Klown, Bibbo, says "Pizza!" to a girl who was cocooned later, by Shorty who was hiding inside the stack of pizza boxes that Bibbo was holding.
• Alliterative Name: Killer Klowns.
• All There in the Script: None of the Klowns are named within the film, not even by the humans giving them nicknames. This is understandable given the alien vibe, but the main Klowns we see do all have names which can be found in supplementary material.
• All Webbed Up: Done using cotton candy instead of webbing. The cotton candy cocoons apparently dissolves the victims enough to be drunk through a silly straw.
• Always Chaotic Evil: The alien invaders are an entire race of Monster Clowns, and are consequently all pure evil. They're essentially space clown vampires, but rather than killing humans only to feed on them, they're all utterly sadistic and genuinely enjoy murdering people in increasingly gruesome ways and laughing psychotically about it.
• Ambiguous Situation:
  • It's possible that the two female Klowns are Earth women captured and converted into Klowns to act as sex slaves, but it is never made clear, and they could just be natural Klowns.
  • It's also not too clear whether the popcorn Klown-snakes that attack Debbie are supposed to be baby Klowns, or people transformed into Klowns (since Slim puts the people he captured with the shadow monster into his popcorn-filled bag, unless he was simply feeding them with humans) or just some kind of bio-weapon.
    • Confirmed by the game to be juvenile Klowns.
• Animate Inanimate Object: Spike manages to create a balloon dog that comes to life, barks, smells, and howls like an actual dog.
• Ancient Astronauts: Mike cites the term directly when he theorizes that a previous visit from the Klowns, hundreds of years ago, gave humanity the idea for clowns.
• Aside Glance:
  • Earlier, after two of the Klowns, Spike and Bibbo get ran over by Mike and Debbie, Spikey gets up and gives a quick glance at the camera before looking at Bibbo, who in turn, gets up.
  • Later, while walking to Big Top Burger, the Klown "Jumbo" stops and looks directly at the camera◊ giving somewhat of a Kubrick Stare before continuing.
• Asshole Victim:
  • Shorty gets upset over a biker who wrecks his tricycle and "knocks his block off".
  • The rabid officer Mooney who roughs up suspects and dismisses the increasing reports of Klown attacks as a mass prank, ultimately gets done in by Jumbo who wanders into his station.
• Attack of the Killer Whatever: Klowns. (From outer space.)
• Auteur License: Written, produced and directed by various Chiodo brothers (directed by Stephen Chiodo and co-written by him and Charles Chiodo).
• Bad People Abuse Animals: The first on-screen casualty of the Klowns' rampage is Farmer Green's pet dog "Pooh Bear". Farmer Green outlives the dog for just a minute or so, though. In the scene where Mike and Dave return to the cotton candy room to find Debbie, you can see a noticeably smaller cocoon behind them, which is supposed to be the dog's.
• Bad Humor Truck: The Terenzi brothers' latest get-rich-quick scheme. Also devised as a way to get fat girls.
• Beware the Silly Ones: True, the Klownz are ridiculous appearance-wise, but all of them are a race of murderous psychopaths.
• Big Bad: Jojo the Klownzilla, who is literally much bigger than all the other Klowns, shows up as their leader in the climax.
• Bigger on the Inside: The Klowns' spaceship combines this with Bizarrchitecture.
• Blunt "No": Mike replies with an amused, smarmy "No" when an increasingly worried Debbie asks him if he's ever seen anything like the interior of the Klown ship before.
• Bloodless Carnage: The Klowns don't seem to bleed. Considering they explode into confetti when their noses are popped, their bodies may contain confetti instead of blood.
• B-Movie: Both a straight example and an Affectionate Parody of the genre.
• Bloody Horror: The victims of the Klowns that are caught in cotton candy cocoons. When opened up, the bodies inside them are a gooey mess. The only exception is one victim who isn’t bloody, but that’s it.
• Boldly Coming: The Terenzi brothers get separated from the other main characters briefly ending next to two lady Klowns. Cut away, and they come back shortly after Covered in Kisses.
  Rich Terenzi: ''Are you Debbie's roommates?''
• Brand X: In the opening the teen played by a young Christopher Titus takes a sip from a can of beer simply labeled "Beer".
• Breast Expansion: The two "female" clowns from the above mentioned scene.
• Brick Joke:
  • The Terenzi brothers fall into a ball pit beside two female Klowns, who leer at them while their...balloons grow. In their next scene, the brothers are Covered in Kisses.
  • A very dark one comes with the characters theorizing about the Klowns' motivations. Rich throws out the silly idea that they're just "cruising through the galaxy, and stopped here for a bite to eat." Soon after, Dave and Mike see that, yeah, that is actually why they're here, as one Klown is seen drinking from a cocooned person he deemed ripe enough for consumption.
• Cassandra Truth: No one believes Mike and Debbie at first, but Dave does begrudgingly take Mike with him to investigate the area. Sgt. Mooney remains convinced that the whole thing is a hoax even after being confronted by a killer klown.
• Chair Reveal: Played with, as we clearly see it's Jumbo, but he nonetheless slowly turns around on the chair to reveal himself when Dave enters the police station.
• Chick Magnet: The Terenzi brothers are this to the female Klowns.
• Chocolate of Romance: In the scene of the Klowns killing people door-to-door, "Fatso" presents himself to a middle aged woman's house to give her a heart-shaped box of chocolates, and pulls out his cotton candy ray gun while the charmed lady has her back turned to ask her husband if he set this up.
• Choke Holds: Once Mooney puts Jumbo behind bars, he finds himself on the receiving end of one, delivered by Jumbo's party blower which unfurls into a hand.
• Cool Starship: It's shaped like a circus tent with a giant luminous spinning cone beneath it.
• Circus of Fear: What the Klowns' mothership is designed as.
• Clown Car: Near the end the evil Klowns relocate to a closed amusement park, arriving in a tiny clown car. The security guard bemusedly watches five Klowns emerge from the vehicle, most of whom are individually larger than the car. This was also how the Terenzi brothers and Dave were able to survive.
• Clown Species: A race of alien Monster Clowns that once visited Earth long ago, their appearance becoming assimilated into mankind's collective consciousness as clowns. Unlike their human copiers, the Klowns are anything but harmless, kidnapping humans to drain them of their blood, using tools normally associated with clowns with a lethal twist to kill or capture humans.
• Covered in Kisses: The Terenzi brothers have gigantic lipstick kisses covering their faces in the next scene after they encounter the female klowns.
• Creepy Circus Music: The score by John Massari has the feel of a demented, out-of-control circus tune to match with the tongue-in-cheek evil circus theme of the titular creatures.
• Cruel and Unusual Death: Really, where do we start?
  • Anyone zapped by the Klowns' cotton-candy guns, as shown in the few times that they're torn open, is dissolved alive inside of them.
  • A biker gets his head punched clean off after harassing Shorty by destroying the latter’s tricycle.
  • A security guard is melted into a puddle of glop and bones with acidic cream pies.
• Creator Cameo:
  • Co-writer Charles Chiodo as Jojo the Klownzilla.
  • According to the commentary, Charles has his back to the camera (miming him peeing) during the initial Top Of The World scene. It's hard to see, though.
• Curiosity Is a Crapshoot:
  • Mike and Debbie went inside the Big Top (the Klowns' UFO that looks like a circus tent) out of curiosity, nearly getting them killed in the process.
  • The Klowns also exploit the humans' curiosity to lure them into traps, such as the little girl back in the burger restaurant and then one of the restaurant's employees who was lured into the garbage dumpster by sounds made by the popcorn seeds Jumbo the Klown (literally) sprinkled in there.
• Dead Guy Puppet: Jumbo uses Mooney as a ventriloquist's dummy in order to talk to Dave, apparently shoving his hand into his back if the blood on his hand when he takes it out is anything to go by.
  Jumbo: Don't worry, Dave, all we want to do is kill ya.
• Defeat Equals Explosion: First, destroy a Klown’s nose. Next, they spin around in the same area where they stand. Then they become encased in a green crystal-esque structure. Finally, they go up in a big boom and shower of confetti.
• Depraved Dwarf: Shorty might be the physically smallest of the Klowns, but he’s still no less dangerous than the rest of them.
• Deuteragonist: Mike and Dave share the protagonist role. Mike is the romantic lead. He's also the one who discovers the threat and leads the early efforts to resist it, and later supplies his knowledge and deductions of the Klowns. Dave is the action hero who discovers the Klowns' weakness, leads the invasion into their tent and destroys their leader and ship.
• Disney Death: Dave and the Terenzi brothers are presumably killed when the spaceship blows up, but they're revealed to have taken shelter in the clown car and emerge unscathed. They were originally killed, but test audiences wanted a lighter ending.
• Dramatically Missing the Point: Farmer Green and his dog "Pooh Bear" become the first casualties of the film because for some reason when Green sees a falling star (in reality, the Klowns' starship) come crashing down into the forest near his home, he decides to go fetch it and maybe even create a tourist attraction out of it, believing that it's Halley's Comet.
• Eaten Alive: The Big Top Burger employee who gets lured and pulled inside the fast food's dumpster by the popcorn Klown hatchlings to get painfully devoured.
• Enemy Rising Behind: The largest of the popcorn Klown spawn rises up behind Debbie from the toilet bowl in this fashion.
• Earth-Shattering Poster: A Klown's finger is spinning it like a basketball. Doesn't really happen in the movie, but it can be seen as a metaphor for what the Klowns are doing to humankind.
• Edible Ammunition: Subverted. The Klowns fire popcorn guns and use cream pies for ammo, except the popcorn eventually transforms into mini-Klown monsters and the cream pies are acidic.
• Enfant Terrible: The newborn baby Klowns.
• The End... Or Is It?: At the end of the movie, The Klowns' ship explodes... and everyone has a "Thank goodness that's over" moment... only to be hit by cream pies. Also, there's still the issue of the snake-like Klown spawn thingies back in Debbie's apartment and at the Big Top Burger's dumpster. And possibly elsewhere.
• E.T. Gave Us Wi-Fi: Mike theorizes that clowns were inspired by the Klowns visiting Earth before.
• Every Car Is a Pinto: Downplayed (due to budget restraints not allowing a second and more spectacular stunt) as the car Slim causes to crash at the end of the Car Chase only catches a bit of fire between the frontal wheels. Played straight and up to eleven with the ice cream truck.
• Evil Puppeteer: Spikey attracts a victim by performing with a Punch & Judy-like stand before firing his cotton candy cocoon gun through a puppet.
• Extendo Boxing Glove: On a closer look, Shorty actually uses that to knock the biker's block off.
• Extremely Short Timespan: The film takes places over the course of one night. It's dark and nighttime as the movie begins and ends.
• Fat Bastard: Most of the Klowns have a pear-shaped physique, but Fatso and Chubby in particular are morbidly obese with very fat, swollen faces. They're so fat in fact that they can barely walk and are forced to hop on one foot at a time to even get around.
• Faux Affably Evil: The Klowns act like this, making shadow puppets seemingly to entertain people only to have them come alive and eat the audience, giving an elderly woman a valentine's box before making her a victim, and so on.
• Females Are More Innocent: The two female Klowns don't actually hurt anyone.
• Fire-Forged Friends: Mike and Dave are practically at each other’s throats at the start, but come to work in tandem and respect each other by the end of the film, to the point that they hug after Dave’s Disney Death.
• Flower Mouth: A snaggle-toothed critter forces the trio to quit descending the bigtop-ship's sliding pole before reaching the bottom, because the end of the pole vanishes into its triple-jawed maw.
• Foreshadowing: The name "Jojo" comes up at least twice in the movie. It turns out that’s the name of the largest and meanest of the Klowns- though you wouldn’t know because no one says it.
• Four-Fingered Hands: The Klowns have them, which makes Slim's shadow puppets all the more ludicrous.
• God Guise: The Terenzi brothers try to fake out the Klowns with their clown-headed ice cream truck, proclaiming it's "the great and powerful Jojo". It gives pause to the regular Klowns, but rouses a giant one to contest "Jojo's" claim.
• Gonk: The Klowns themselves are utterly hideous.
• Hammerspace: Frequently invoked on the part of the Klowns, producing items from nowhere between shots, and in one case, Shorty pops out of a pizza box.
• Humanoid Aliens: The Klowns look like hideous and distorted human clowns. Their juveniles are more bizarre, being mostly heads and necks.
• Humans Are Morons: With the exception of Mike, Debbie, Dave and the Terenzi brothers, humans are easy, gullible prey to the Klowns' traps.
• Idiot Ball:
  • As indicated above, pretty much everyone that isn't at the final showdown is one. The people of Crescent Cove enjoy clowns WAY too much, because they never question any of the Klowns' antics until they show their true colors and use lethal force. For the unnamed characters, special mention goes to the mother who only stops her little girl from being crushed to a pulp by Jumbo because said little girl HASN'T BEEN EXCUSED FROM THE TABLE YET.
  • And, of course, the crowning jewel of the Idiot Ball in this film is Officer Kurt Mooney, who, when the Klowns start openly and overtly attacking people, believes the entire town is in on a nonexistent practical joke, despite how little actual sense that makes.
• I'm Melting!: Near the end the Klowns dispose of a security guard by showering him with throwing pies... which promptly melt him down to a pile of bones.
• Impossible Shadow Puppets: Slim makes hand shadows of a variety of complicated subjects that seem to bear no relation to the movements we see of its stubby fingers. At one point it makes a shadow puppet of Washington crossing the Delaware. Then it makes the shadow of a Terrifying Tyrannosaur that swallows its audience.
• Improbable Infant Survival: Jumbo beckons a child to come to him... whilst secretly holding a mallet behind his back, clearly planning on murdering her. If her mom hadn't managed to stop her just in the nick of time — and entirely for the wrong reason at that — the little girl would have died gruesomely.
  • Though there's still the possibility that either Jumbo waited for her and killed her afterwards or she may have been cocooned later with the rest of the townsfolk, unless her family lives outside and left after dinner before the invasion.
• I Never Told You My Name: The Klowns somehow know the names of their human victims without even being told so.
• Informed Ability: The Terenzi Brothers are supposed to be master pranksters of some sort (especially because Mooney's assumption that the Klowns are a prank depends on believing that the Terenzis are the masterminds and that they managed to convince the whole town to be in on it). We only see them doing one prank in the film's prologue and it's not a good one.
• Irony: From Mooney. "You're not gonna make a dummy out of me!"
• It's All About Me: Mooney decides to stop listening to any calls for help, including one from his direct superior (Dave), because he thinks somehow that the whole town got together under the leadership of the Terenzi Brothers to try to swindle him into quitting being a cop, instead of the more obvious possible reason that there are a lot of crazy people dressed as clowns causing mayhem (considering he makes clear he doesn't believe Mike when he talks about the Klowns being aliens).
• Kaiju: Jojo, the 18 foot tall Klown leader appropriately nicknamed "Klownzilla".
• Keystone Army: The spaceship blows up when Jojo the Klownzilla is killed. This may also be due to his explosion being larger and more powerful due to his size.
• Knight of Cerebus: Jumbo is definitely the most sadistic of the Klowns. He provides 2 of the most threatening scenes in the movie. He tries luring a child outside a restaurant so he can beat her to death with a mallet and when he kills Mooney, he proceeds to use his corpse as ventriloquists dummy so he can speak to Dave.
  Mooney-Jumbo: "Don't worry, Dave. All we wanna do is kill ya".
• Laughably Evil: This is naturally the space Klowns' shtick. They kill people by using normally comedic circus-like magic tricks, but with lethal results—showering people in acid pies, cocooning them in cotton candy, consuming them with shadow puppets, making ventriloquist dummies out their corpses, etc. Evil Laugh optional, but advised.
• Large and in Charge: Klownzilla. Also Jumbo, who is the largest of the regular Klowns and is the most sinister.
• Living Shadow: Slim entertains a crowd with Impossible Shadow Puppets before creating a T-Rex one and devouring them with it, shrinking them down to miniature size so that he can feed them to juvenile Klowns in their popcorn phase.
• Living Toys: Early in the film, Spike creates a balloon-animal dog that actually barks and follows a scent-trail much like police dogs.
• Load-Bearing Boss: Jojo the Klownzilla, who blows up the entire Klown ship upon dying.
• Long Neck: Possibly applicable to the Klown-spawn that arise from the popcorn on Debbie's discarded sweater, although we never seen what the necks are attached to so they could be snake-like instead.
• Love Triangle: Between Debbie, her current boyfriend Mike and her ex-boyfriend Dave. Word Of God says Dave probably wins.
• Made of Explodium: Klownzilla throwing the ice cream truck aside causes it to blow up spectacularly.
• Make-Out Point: "Top of the World," where all the local teens go to make out in their cars beneath the stars. It's near where the Klowns land. Christopher Titus makes his film debut as one of the unfortunate teens.
• Mars Needs Women: Implied. The Klowns trap human women inside balloons possibly to convert them into female Klowns.
• Mistaken for Prank Call: Officer Mooney dismisses all of the Klown attack reports (and Dave requesting backup over the radio) as a town-wide prank by the Terenzi Brothers aimed at him.
  Officer Mooney: [after listening to a man reporting a Klown attack] They took your wife away in a balloon? Well you don't need the police, pal, you need a psychiatrist! [hangs up]
• Moment Killer: With their abrasive, jingling ice cream truck entrance, the The Terenzi Brothers manage to ruin the vibe to all the parked couples trying to make out at the "Top of the World", who understandably respond by mocking them into leaving and throwing stuff at them.
• Monster Clown: The Klowns are hideous, yet no one seems to notice, treating them as ordinary clowns if they notice them at all.
• Mugging the Monster:
  • Mooney tries a little Police Brutality on Jumbo, thinking it's a prankster in a costume. It ends badly, and he gets turned into a Dead Guy Puppet.
  • A gang of bikers decide to pick on Shorty by wrecking his bike. He decapitates the offending biker.
• Ninja Pirate Zombie Robot: The Klowns are in fact, Monster Clown Vampires From Space.
• Oh, Crap!: Happens quite a lot among the characters. Some examples include:
  • When Debbie and Mike stumble upon the cotton candy cocoon storage room. Debbie is already nervous from the Big Top experience while Mike is unconcerned. Then Mike tears a piece from the cocoon off and reveals a corpse and now the two are horrified and wonder who would even do this. Doubly so since one of the Klowns, Rudy, comes in with a new cocoon and the two have to hide, only for Mike to drop his lantern, alerting the Klown to their presence.
  • The biker gang who fled in fear when they saw Shorty knocking the block off one of their members.
  • When Dave shoots Jumbo in the nose, the Klown gets a terrified look on his face and roars in both fear and agony right before he spins and explodes.
  • Mike, Dave, and Debbie get terror-strickened when seeing the Klowns surround them with clubs all with murderous intent. Then Mike, Dave, Debbie, and the Terenzi brothers as well as the Klowns themselves get filled with fear and look as if they soiled themselves when Klownzilla makes his entrance.
• Off with His Head!: A biker gets his block literally knocked off by Shorty, which is the punchline to the biker's incredulous question.
  Biker: What are you gonna do, knock my block off? [Shorty proceeds to do just that]
• Only the Leads Get a Happy Ending: All of the five main characters survive, Dave and the Terenzi brothers even get a Disney Death when they're shown to have survived the explosion of the Klown spaceship after all. At the same time, their entire hometown (or a very good portion at least) has been wiped out by the Klown invasion, which is ignored with a pre-credits pie gag. While in the ship, Dave does suggest trying to free the people trapped in the other balloons, but then the Klowns show up and they have no time to save anyone but themselves
• One-Book Author: The Chiodo brothers primarily design creature and makeup effects, as well as doing puppetry, and this is the only film they wrote or directed. Their other work includes designing the "troll" effects for Ernest Scared Stupid, the 'Crites' in the Critters film series, the animation for the "6000 SUX" commercial in RoboCop (1987), the titles for the Thriller music video, and the "ghost" animatronics for Universal Studios' Ghostbusters Spooktacular. They've also provided puppets, animatronics, models and Stop Motion in other shows and films, such as Charlie Horse Music Pizza, Ninja Turtles: The Next Mutation, Adventures in Wonderland, Gremlins (1984), I Go Pogo, Goosebumps (1995), The Simpsons, Power Rangers Turbo (and its movie), Power Rangers in Space, Team America: World Police, Screamers, Masked Rider, The Stupids, It Came from the Desert (1992), The Mr. Potato Head Show, Sabrina the Teenage Witch, Roseanne, The Thundermans, Bibleman, Elf, and Pee-wee's Big Adventure.
• Only Sane Woman: Debbie demonstrates to be the most down-to-Earth character among the humans, as she's unwilling to go explore a strange circus tent in the woods (the Klown ship) and quickly deduces that it's some extraterrestrial handiwork, while Mike suffers from some Genre Blindness and makes bad rationalizations until he sees dead people.
• Our Vampires Are Different: They're alien beings who visually resemble grotesque, somewhat reptilian clowns, and they use ray-guns that envelop victims in cocoons of cotton candy that dissolve them, implying that what the Klowns drink is less "blood" and more "liquefied flesh".
• Peek-a-Boo Corpse:
  • Mike tearing off some cotton candy from a cocoon revealing the face of a partially liquefied victim to Debbie's horror and to his own shock.
  • Done with the arm of the arrested punk sliding out of his cocoon and onto Dave startling him when he inspects the prison cell ravaged by Jumbo.
• People Puppets: Mooney after being killed by Jumbo.
• Pie in the Face: Five of the Klowns throw acidic pies at a security guard, which reduces him to a pile of bones and whipped cream, ending with Shorty sticking a giant cherry on top. Interesting to note that the pies used were not the traditional pie tin with whipped cream, but actual fruit pies that hit the guy with quite a bit of visible force. Also, they had to put hand straps on the tins so they weren't flying with the pies and covering the actor.
• Pint-Sized Powerhouse: Shorty knocks the male biker's head clean off with a single punch in retaliation for demolishing the Klown’s tricycle. Justified because the Klowns are actually extraterrestrial monsters, so of course they would have the high chance of being inhumanly strong.
• Play-Along Prisoner: Jumbo allows himself to be taken prisoner, apparently just to toy with Mooney. Once Mooney starts getting aggressive, he returns in spades.
• Police Are Useless: Zigzagged.
  • Mooney is a completely useless cop who spends his time harassing local college students for drinking in the park. When the klowns arrive, he's absolutely convinced that they're a hoax perpetrated by the entire town and refuses to look into the mounting reports, despite the fact that no matter how ridiculous, this should be at least a cause for concern.
  • Dave is understandably dubious about Mike and Debbie's claims, but agrees to investigate. Once he gets a load of what's going on, he becomes an action hero. In the end, he saves the day and takes down the Big Bad Klownzilla.
  • The security at the theme park where the Klowns parked their circus tent (spaceship, really) has no clue what he's going up against, when he sees them pulling out pies he doesn't know what they'll do next.
  • Crescent Cove's police force seems understaffed to say the least. At night, only Mooney and Hanson are on active duty (a single line does mention the Chief is on vacation). The rest of the state police do show up at the end, but they are too late to actually help anyone, arriving just in time to see the spaceship explode and the survivors escape.
• Police Brutality: Mooney first arrests two college boys for public intoxication, then starts beating them up, forcing Dave to intervene.
• Precision F-Strike: "It's gonna take a lot more than a lame prank like this to get Curtis Mooney to throw in his badge, so fuck you! Over!"
• Rabid Cop: Officer Mooney has to be almost physically restrained from beating up a couple of punks ^note  as in, leather jackets and probably listen to The Ramones as opposed to dangerous hooligans, not that Mooney would acknowledge any difference brought in for public drunkenness. He later takes a flashlight to the head of one of the Klowns, which turns out to be not such a hot idea.
• Rape, Pillage, and Burn: The male Klowns do the last two, the female Klowns do the first one.
• Ray Gun: The Klowns’ main weapon of choice is a ray gun that wraps people in a cotton candy cocoon which turns them into a drinkable gelatinous goo, sort of like a spider's CapriSun pouch, if you will.
• Red Shirt: Farmer Green. He even wears a red flannel!
• Riddle for the Ages: Where the Klowns come from and why everything they do is clown-themed. Mike suggests that they visited Earth centuries before and provided the basis for the human concept of clowns, but it's left unanswered.
• Rule of Funny: Invoked and Subverted: when escaping from the Klown ship the first time, Debbie questions why the Klown (Rudy) fired popcorn at them, to which Mike responds: "Because they're clowns, that's why!", though later we find out that the popcorn grows into voracious Klown-spawn that attack Debbie, thus Rudy wanted to feed the babies and ensure the doom of the human intruders.
• Sadist: All of the Klowns take joy in killing people and terrorizing the protagonists.
• Scary Jack-in-the-Box: The popcorn Klown spawn are meant to invoke this, with their long bodies looking like organic springs.
• Screw This, I'm Outta Here!:
  • The moment Mike discovers the true nature of the cotton candy cocoons, he decides to listen to Debbie and get the hell out of the Klown ship ASAP.
  • The motorcycle gang running away in a panic when their friend gets killed by Shorty for breaking his bike.
  • The Klowns running out of Klownzilla's chamber when they see him coming down.
• Scully Syndrome: A truly unsympathetic example. Mooney's alternate theory about the Klowns' attack is that it is a prank done by the entire town and somehow orchestrated by the Terenzi Brothers to drive Mooney nuts and make him decide to quit being a cop. The theory has the obvious issues of 1) the Terenzis having to make everybody in town (including fellow Officer Dave, who for all Mooney seems to loathe him is quite obviously too law-abiding to do this) agree to prank-call Mooney, 2) everybody in town keeping quiet about this until they execute the plan, 3) everybody in town loathing Mooney that much, 4) that the more realistic calls for help about crazies in clown make-up assaulting people are also part of the prank calls and 5) Dave is willing to risk his own badge alongside Mooney's when he calls Mooney and asks him to call for backup next town over, considering the cops over there won't take being prank-called lightly (and if somehow Dave convinced the cops from the surrounding towns to be part of the prank they also fit the previous points).
• To Serve Man: The reason the Klowns came to earth (besides to have fun killing some people) was to harvest people for consumption, with this reveal being shown when Chubby uses a straw to drink from a cotton candy cocoon.
• Sexy Jester: The Terenzi brothers seem to think the two female Klowns are this, but most viewers wouldn't agree.
• Shout-Out:
  • To The Blob (1958) as the first half of the film follows similar beats: opening with the teen protagonists making out at night in their vehicle before being distracted by a falling star-looking object which turns out to be an alien threat, a curious old man leaving his cabin to inspect the landing site of said alien threat and becoming the first victim, while the teens aren't believed when they tell the police. Officer Mooney even appears to be based off of Sgt. Jim Bert from The Blob.
  • To Forbidden Planet, with the power core room Debbie and Mike walk into during their exploration of the Klown ship being inspired by the Great Krell Machine.
  • To Dumbo when four of the Klowns appear beneath Debbie's window holding a small trampoline and wearing fire helmets.
  • To The Wizard of Oz when Rich poses as the "Great and Powerful" Jojo like how Oz proclaims himself when he appears as a giant head.
  • To Alien, with the film's tagline "In space no one can eat ice cream!" being a punny parody of Alien's "In space no one can hear you scream".
• Shower Scene: Debbie takes a shower and apparently spends a good half-hour in there while the popcorn Klown larva gestate. Given the PG-13 rating, it's not played for fanservice.
• Skewed Priorities: When Jojo the Klownzilla comes to destroy the ice cream truck, Dave orders the Terenzi brothers to get out of there but they can't because the ice cream truck they're using is rented.
• Sliding Scale of Comedy and Horror: Largely balanced. The film is played surprisingly straight for such a silly premise which the filmmakers wisely didn't take too seriously. The Klowns are very often Laughably Evil, but the movie keeps some genuine scares for even non-coulrophobes.
• Spoofs "R" Us: Invoked when Mike jokes that the interior of the Klown ship "Looks like it was decorated by Clowns R Us".
• Squirting Flower Gag: When Jumbo visits officer Mooney in his office, he offers Mooney a bouquet of flowers that end up spraying water in his face. Surprisingly, although the Klowns are usually fond of putting deadly spins on these classic pranks, it really is just water and all it does is piss Mooney off (at this point Jumbo was still toying with Mooney rather than planning to kill him).
• Standard Snippet: The main riff of the title theme by the Dickies is based on "Entry of the Gladiators" by Julius Fucik, and it gets used more fully toward the end of the song.
• Starfish Aliens: Though the adults are humanoid, the Klowns seem to start life as popcorn, then grow into snakes with clown heads.
• Stripped to the Bone: Acidic custard pies, as this was the case with the security guard.
• Sure, Let's Go with That: The Terenzi brothers are resistant to help Mike and Dave, but display sudden interest when they mention that Debbie's in danger, and the Terenzis ask if Debbie has roommates. Mike lies and goes along with it, saying yes, she has two roommates, with big boobs, and affirms that they like ice cream when the Terenzis ask.
• Technicolor Death: The only way to kill a Klown is by popping their noses, which makes them spin around in a green light show before exploding into confetti. All in all, killing a Klown is just as dangerous as blowing up dynamite within a blast radius you risk being in, but just letting the Klown live is an even worse choice.
• Terror at Make-Out Point: The first place the Killer Klowns go to so they can harvest humans for their blood is the teenage make-out spot. When the heroes later inspect the place, they find only cars full of cotton candy and a pair of glasses.
• Threesome Subtext: Even given they're surviving a horrific ordeal together, Mike, Dave, and Debbie do seem very affectionate. Especially between Mike and Dave considering they just met and Mike is dating Dave's ex Debbie whom Dave isn't over yet. Not just the hug at the end; throughout the second half of the film take note of their interactions and body language.
• Threw My Bike on the Roof: A group of bikers bully Shorty who arrives on a mini-tricycle by destroying it and laughing to each other. Unfortunately for them, he is actually a vampiric extra-terrestrial monster, so he decapitates the biker who crushed it in question. The rest of the gang wisely took off after that.
• Title Drop: Mooney overhears Mike and Debbie's story and sarcastically comments, "Killer clowns from outer space? Ho-ly shit!"
• Title Theme Tune: "Killer Klowns From Outer Space" by The Dickies.
• To Serve Man: The Klowns capture people and trap them inside cotton candy cocoons (killing the victim in the process) so that they decompose into a sweet red liquid for the Klowns to drink.
• Too Dumb to Live: The uncocooned citizen during the Klown parade scene who could've survived had he just waited until they were gone. Admittedly the Klowns themselves to an extent; they have figured out advanced space travel, but can't be bothered to protect their nose, which is their only Achilles' Heel.
• Troll: The Klowns have a habit of messing with their victims rather than just zapping them. Some memorable highlights include the Klowns delivering pizza and chocolates to peoples' houses, Jumbo spraying Mooney with a water-spraying flower and then letting himself be arrested, and Slim performing a puppet show.
• Two Girls to a Team: Only two female, Klowns, named Rosebud and Daisy, are seen.
• The Unintelligible: Zig-zagged with the Klowns. While they have a bizarre alien babble when speaking to each other, when interacting with humans, they approximate English to a point of intelligibility. Bibbo says "Pizza!" and "Mmm hmmm". (For example, Shorty can be understood to be saying "put up your dukes" before boxing the biker.) And when Jumbo puppets Mooney and makes him talk, it seems to be his own sentiment, somehow gaining a voice through Mooney. Slim also imitates Mike's voice to perfection to lure out Debbie.
• Unusually Uninteresting Sight: The first time Rudy encounters people in town, it pretends to be an animatronic to avoid notice. After that scene, the Klowns drop all pretense of hiding, which is just as well, since no one in the entire film reacts to their grotesque appearance. When they're noticed at all, they're treated as looking like normal clowns, though their destructive actions certainly get attention.
• Vehicle Vanish: Inverted. Slim suddenly appears at the bus stop next to his soon-to-be victims after a bus passes in front of the camera.
• Villain: Exit, Stage Left: Since according to Word of God many Klowns are actually still alive after the destruction of the Big Top Ship, it makes the Klowns hurrying out of Klownzilla's chamber as he descends this.
• Visual Pun: The Klowns' "Big Top" tent/spaceship, when it takes off at the end of the movie, is revealed to actually be shaped like a big spinning top.
• Voice Changeling: Slim the Klown imitates Mike's voice when he arrives at Debbie's doorstep.
• Wall Crawl: Shown when Dave returns to the police station, and sees Jumbo's colorful footprints on every wall of the cell block.
• Weaponized Offspring: The Popcorn the Killer Klowns bring with them are the babies of the species, which are launched as projectiles from shotgun like artillery. This is likely meant to spread their young closer towards human environments where they would quick grow and aid the klowns in their hunting trip.
• What Are You in For?: Asked of to Jumbo by a fellow prisoner after Jumbo allows himself to be locked in the town jail.
• What Happened to the Mouse?: The two female clowns disappear after their one scene. Though they most likely die when the Klown ship blows up.
• Would Hurt a Child: The Klowns would, but the movie's creators wouldn't. One girl who was at a burger restaurant gets lured out by Jumbo who planned on smashing her head in with a mallet. Her mother stops her in time, making Jumbo angrily shriek.
• Xtreme Kool Letterz: The spelling of "Killer Klowns" in the title.
• You Are Too Late: Mike takes Dave back to see the circus tent which is gone. Oddly enough, the huge hole it left behind does not count as any evidence of anything strange to Dave, who promptly handcuffs Mike for filing a false report.
• You Get What You Pay For: A positive example of this trope. The Terenzi brothers refuse to abandon the truck to escape the clown's spaceship since it was rented. This gives Klownzilla enough time to throw the truck, causing it to explode into a fiery grave. It turns out they survived by hiding in the apparently very well reinforced freezer and jumping into the clown car escape pod in the nick of time. It's never shown how much they paid to rent it, but if the duo were afraid of having to pay the damages, the reinforced freezer implies they did not get ripped off.