A basic, classic horror plot that follows a simple formula.
Some characters are stuck in a partly constricted space (such as a building or large vehicle), while menaced by some threat, usually a vicious predator that is hunting them. The cast avoids the predator to the best of their ability while trying to concoct a method of resistance and/or escape. If initially more than a few people, their number dwindles as they are devoured or otherwise disposed of one after another, until such time as the predator is defeated or they manage to engineer an exit. The essence of the trope is the immediacy of the conflict between victims and predator. The victims have no chance to flee or withdraw from the situation to form an ideal plan. With every moment, the risk of an encounter with the predator is mounting. Any plans need to be thought up fast, and every loss reduces the victims' chances permanently.
Circumstances ensure that the characters can't simply leave the situation. If they're in a structure, it will be somehow isolated or surrounded by a hazard. The most common choices are a space station or an underwater habitat, where the environment around the enclosed space is also dangerous without proper protection. A vehicle will usually be something equally enclosed and inescapable, like a plane, submarine, boat, or spaceship. If a land vehicle, it will have to be traveling through an inhospitable area, like a desert. The area has to be of sufficient size to ensure some kind of story can happen, so a single room of a house or a four-door car won't work. Similarly, the space can't be so large that the prey can just keep running away, like a wide-open field.
The isolation creates an environment with a lot of potentials. There are cubbies, alcoves, and storage areas to hide in; corridors to run through; air vents to sneak through; open, communal areas that create the illusion of safety. There is also maintenance equipment that can be used as an Improvised Weapon; devices and instruments that can be reconfigured as traps. Any of these can be used by the protagonists or the creature in their perpetual game of cat-and-mouse.
The use of a vehicle adds further complications. If operational, it imposes a time limit on the story, as it will (hypothetically) eventually carry everyone to safety; thus, the protagonists in principle need only survive long enough for it to arrive. If not operational, getting it running will be the major goal for at least the first act. This, in turn, creates an extra level of threat, as the monster can, if unable to reach the protagonists, still screw them over by wrecking their transportation.
Compare Shark Pool and Fed to the Beast, where the villain intentionally puts the hero in a confined space with a monster. Often coincides with Exploring the Evil Lair. Contrast Alone with the Psycho. "Die Hard" on an X is the inversion of this, where the "monster" is the hero; a common joke among fans of Alien is that, for a xenomorph audience, that film would be Die Hard on a space freighter.
- Played with in the "Homeschooling" arc of Runaways, in which an accident causes Klara to trap her teammates inside their Malibu house. Victor grows increasingly convinced that Klara's powers are a danger to them all, but it later turns out that she's actually protecting the team from a paramilitary group that has shown up to investigate and "contain" the accident (i.e. kill all witnesses and destroy all the evidence.)
- Wonder Woman (1987): During The Contest it's revealed that during the months since Themyscira's apparent destruction by Circe's magic the place has actually been trapped in a small pocket dimension full of demons for ten years with the demons constantly slaughtering and hunting the Amazons as they fought to survive.
- Inevitable, given the series it's based on, but Something Always Remains has Mike spending six hours a night trapped with murderous aninatronics in order to try to figure out what happened to Jeremy Fitzgerald. As mentioned below in the video game section, it's downplayed, as he's there willingly. It's played more horribly straight when Jeremy ends up trapped because he wasn't supposed to be there that night, and everything he does to protect himself screws him over.
- In Alien, a highly ferocious extraterrestrial menaces the crew of a freighter spaceship. It is, though not the Trope Codifier, one of the most famous examples in sci-fi. As such, many subsequent sci-fi works following this trope are homages. Almost all of its many sequels, tie-ins, and crossovers have followed the same format.
- In Crawl, Haley and her father are trapped in their house by an incoming category 5 hurricane, which prevents them from easily getting help. To make matters worse, a group of alligators have moved into the house with the rising floodwaters, and alligators can swim better than humans can.
- In Horror Express people are trapped on the Trans-Siberian Express train with a prehistoric monster which was found frozen in ice but has thawed out.
- The premise of John Carpenter's The Thing is that a polymorphic alien crashed on Earth during the Ice Age, and has been in suspended animation in Antarctica until some Norwegian researchers discovered it. The alien wiped out their compound and fled to the American base disguised as a sled dog. Given enough time, the alien can mimic any organism it consumes, and the American researchers have nowhere to flee that isn't sub-zero cold.
- The researchers on Saturn 3 see a shuttlecraft / supply ship once every six months. When obsessive psychopath Benson joins them and builds a mind-linked super-robot, the robot downloads Benson's psychoses and begins lusting after nubile Alex. Retreat becomes impossible when the robot destroys the only launch capable craft on their moon.
- Fer-de-Lance is a 1974 TV movie about a submarine trapped on the ocean floor with escaped poisonous snakes running loose.
- It's a slightly larger space, but Tremors has a similar plot. The residents of a small desert town are menaced by giant SandWorms, and must try to survive. They can't easily leave because there is only one road out of town and it has been blocked by the worms and attempting to leave on foot would be suicide.
- Tremors 2: Aftershocks: Same deal as the first film, but this time the group of humans have to deal with the smaller, more numerous, bipedal offshoot of the Graboids, which they dub "Shriekers" on account of the sound they make. While it doesn't hunt based on sound (being both blind and deaf), it can detect any heat signature, which also causes them to attack all machinery including car engines, disabling it, and trying to run from them in a wide open space is similarly suicidal.
- Tremors 6: A Cold Day in Hell: The group is stuck at the facility with no cars or high-power weaponry. They're also situated in a geographically isolated valley with mountains on all sides, which gets a Lampshade Hanging from Burt. He further notes that it's only a matter of time before a Graboid starts smashing through the floorboards to get them.
- The Abyss has a twist — the crew of an experimental seafloor habitat encounter aliens, but these turn out to be benign (ish), and one of their own members is the real threat.
- Event Horizon: An experimental hyperdrive goes horribly wrong.
- Snakes on a Plane is basically this trope played up to the most troperiffic possible level.
- Predators features a group of hardened mercenaries and murderers, general scum of the earth, sent offworld to the hunting grounds of a trio of Predators who systematically hunt them down.
- In Bait 3D, a group of people are trapped in a partially submerged convenience store with two great white sharks after a tsunami devastates the coastal town.
- In Deep Blue Sea, a group of scientists are trapped inside an underwater research laboratory with three genetically enhanced sharks. It also happens over the weekend, meaning that most of the facility's personnel is on leave, leaving only a skeleton crew of about 10 people to deal with the sharks.
- In The Ruins (and the book it's based on), a backpacking group is trapped on a Mayan temple, the ruins of which are covered with an intelligent plant with a craving for human blood. Slightly twisted in that the humans and the plant are both trapped by a group of natives who are keeping the plant from spreading any further by burning and salting the earth around the temple; once the ignorant tourists have entered the ring of salt, the natives keep them penned up as well, knowing that the plant can infect them.
- Most of Deep Rising takes place on a stalled cruise ship. Although the protagonists do have a boat of their own, its engines are damaged in a collision early on, so it won't be able to take them to safety unless they can retrieve replacement parts from the tentacle-infested cruise ship's machine shop.
- It! The Terror from Beyond Space has various astronauts trapped with a blood-sucking Nigh-Invulnerable Martian inside of a rocket that is in the middle of its four-month journey back to Earth from Mars. Essentially a prototypical Alien made in The '50s (and not really that odd—it was one of Dan O'Bannon's favorite films).
- Train to Busan has an increasingly-dwindling number of humans trapped with an increasingly-growing horde of zombies on a train en route to a safe zone.
- Also provides the page image.
- Trench 11: An early grenade explosion destroys the entrance and forces the men to find an exit tunnel while the infected roam the halls.
- A Quiet Place: The mother is trapped with one of the monsters in the house a couple of times and is forced to be incredibly quiet lest the creature's powerful hearing picks up on her. The kicker? The first time, she's on the verge of giving birth.
- Most of the films from the Jurassic Park franchise use this trope, although they alternate the Trapped With Carnivorous Dinosaurs action scenes with Aesops about not messing with nature and The World Is Just Awesome shots of non-predator dinosaurs looking dramatic.
- Charlie and the Great Glass Elevator has a major portion devoted to Charlie et al. visiting a Space Hilton that has been taken over by vermicious knids. In this case, because they came in the titular elevator they are able to just leave again, though it's a narrow escape.
- Life of Pi: Kid trapped in a lifeboat with a tiger.
- In Ciaphas Cain: The Emperor's Finest, Cain ends up trapped aboard a space hulk after getting separated from his Space Marine companions by a tyranid attack (note: the tyranids are based in part on the xenomorphs from Alien), and spends the rest of the book having to evade both them and a party of orks that are also aboard. Then he has the bright idea to trick them into fighting each other, making the Space Marines' job a heck of a lot easier after he gets back to them.
- The Goosebumps book How to Kill a Monster is about Gretchen and Clark, siblings sent to stay with their grandparents at their huge house by the swamp while their parents travel on business. They notice that their grandparents are hiding something upstairs and cooking more food than any human could ever eat, and while playing a game, and eventually learn that there is a swamp monster lurking in the house. The grandparents have left to try finding help (Gretchen pointing out to Clark that nobody will believe them when they say a monster's in their house) and decided to leave the kids locked inside the house, saying it's safer inside than in the swamp, rather than take the kids with them, forcing Gretchen and Clark to fight back. The Twist Ending of the book makes it worse—the kids do successfully escape the beast and flee into the swamp...only to learn, too late, that the monster had many siblings. And now they're out in the middle of the bog with all of them.
- Doctor Who uses this often, frequently with reference to Alien. Because the principal narrative device in the series is the TARDIS, which is literally as big inside as the writers want it to be, an easy episode to write is "some monster invades the TARDIS and everyone has to flee it until the Doctor figures out how to defeat it." New series examples include:
- "The Impossible Planet" and it's second part "The Satan Pit" are set on a planet somehow hanging just next to a black hole, turns out the planet is a prison for a being who looks and claims to be the inspiration for Satan, then it possesses the stations army of meek, servile Ood, trapping them all in an attempt to break free.
- "42": One of a space freighter's crew is possessed by a sentient star and becomes bent on spreading its influence to the rest. A subplot concerns trying to reach and repair the main engine to get away from said star before the ship falls into it.
- Two Parter "Silence in the Library" & "Forest of the Dead" is a particularly fiendish aversion to the usual method of the characters trying to hide in shadows to avoid the monster, being that the Big Bad of the episodes is is the shadows, weeell, to be more technical, The Creatures, the Vashta Nerada, are so tiny but numerous they look like shadows, but can pull a feeding frenzy extremely quickly, as demonstrated by the Doctor throwing a chicken leg into a shadow, and it is Stripped to the Bone the second it hits the shadow, they also later prove to be extremely intelligent later when the Vashta Nerada learn to pull a Puppeteer Parasite on people they have killed.
- "Midnight": In an interesting twist, the vehicle is only the size of a small room, with rescue on the way, but the monster hunts the characters through labyrinths that are psychological rather than physical: it takes them over by repeating their words, in a process that is never entirely explained.
- "The Waters of Mars" Finds the Doctor trapped on humanity's first Mars colonisation base, which he knows is Doomed by Canon due to his time travel adventures, he doesn't know why, however, it turns out a glacier on Mars which the base uses for water is a prison for a parasite which can overtake anyone with a single drop of water, and the Doctor must decide whether to save the remaining crew or let them die to preserve history.
- "The Curse of the Black Spot": The crew of a becalmed pirate ship is hunted by a siren who targets anyone with an injury or health deficiency.
- "The Doctor's Wife" has a moment of this, when House takes over the TARDIS and sends Amy and Rory scurrying around the corridors. Mostly he plays with their heads in an Interface Screw type of way, but he also sends his pet Ood, Nephew, after them to finish them off.
- "The God Complex": A spaceship/prison traps people in what seems like an infinitely recursive hotel while a minotaur chases them down.
- "Cold War": A Martian Ice Warrior is discovered and thawed by a Soviet nuclear submarine during the '80s. It spends a lot of time hiding in air vents and Neck Lifting people, and the rest of the time trying to fire the sub's missiles in a deliberate gambit to start a nuclear war.
- "Journey to the Centre of the TARDIS": What starts as a search for Clara, who has gotten lost somewhere in the bowels of the damaged TARDIS, becomes a flight from a handful of burnt zombie-creatures.
- "Mummy on the Orient Express": A train, reconstructed for space travel, harbors a mummy-like creature called the Foretold that drains the life from its victims one at a time.
- In the Stargate SG-1 episode "The Tomb", SG-1 and a prototype SG team from the Russian Air Force get trapped in the tomb of the Goa'uld System Lord Marduk, and it turns out there's a critter of some kind in there with them that starts attacking them. It turns out to be a critter that Marduk's priests entombed with his sarcophagus to slowly kill him, but the symbiote jumped hosts to it.
- The Star Trek: Deep Space Nine episode "Empok Nor" has a squad from Deep Space 9 trapped aboard its sister station Empok Nor by a unit of Cardassian black ops soldiers left behind in stasis as a booby trap. There's also a gas in the air that causes Cardassians to become violently xenophobic, which makes Garak take over as the monster after he kills the last soldier.
- Wizards of Waverly Place: In "Night at the Lazerama", Justin and Juliet go hunting for a mummy in the museum and get trapped there when it closes for the day. Since looking into the mummy's gaze will make one his mind slave, Justin suggests they try to avoid him until morning, which is bad news for his vampire girlfriend. In the end, Juliet willingly stares at the mummy to save Justin.
- In Mother 3, there is a segment in which your party is locked inside a chimera research lab. It's not long before the experiments start getting uncaged, including the lab's magnum opus, the Ultimate Chimera. It's not exactly friendly.
- Alien: Isolation is a Survival Horror game in the Alien franchise with the player character trapped aboard a space station with a xenomorph that killed the entire crew.
- Dead by Daylight: The standard format of the game is four Survivors are trapped in a map with a single Killer. The Survivors must avoid the Killer's attempt to shove them onto sacrificial hooks while also repairing generators that will power the Exit Gates and allow them to be opened so they can escape.
- Dead Space
- The original Dead Space has protagonist Isaac Clarke and a few members of his crew trapped on a spaceship filled with necromorphs. They can't just leave because their Mission Control insists on completing their rescue mission for any potential survivors, and many of the ship's systems need to be fixed. Even when systems get fixed and the rescue mission is called off, the necromorphs have becomes such a threat that finding a capable escape plan is difficult.
- Dead Space 2 sees Isaac Clarke needing to find and destroy the Marker, an artifact that's severely messing with his mind. While the necromorphs are back, they're less of an obstacle to escape than needing to find and destroy the Marker. Isaac can't just leave the space station he's on because if he does, the Marker will drive him permanently insane.
- Five Nights at Freddy's and its sequel downplay this; you're stuck in a building full of murderous animatronics, but you're willingly in there for a (minimum wage) paycheck. The sixth night of the sequel, though, does this more literally: you missed a memo and weren't supposed to be at the building that night. You're then encouraged to stay there and hold out until the robots shut off at 6 am, rather than try to escape out of there in the dark.
- Observer takes place in a run-down apartment complex that's been set on lockdown for reasons unknown, and Dan Lazarski is trapped inside along with all its tenants, some of whom have been murdered by a human-wolf hybrid stalking the building.
- Until Dawn traps the eight protagonists with the Psycho on a frozen mountaintop in a snowstorm. The only way down is a cable car that's been moved too far away for them to be able to jump to it, and the key that would activate the cable car missing. Even after the Psycho has been dealt with, Wendigoes begin showing up, further escalating the situation. This time, the victims have no idea how to fight back at first, because their attacker isn't human. Also, while the victims do manage to radio for help and a way to escape in the form of a helicopter, it won't arrive until dawn. Unusually for this type of plot, it's possible to mostly avoid the "dwindling numbers" aspect of the story; though difficult, all eight playable characters can survive.
- One level in the third, swamp-based chapter of Sly Cooper and the Thievius Raccoonus sees Sly investigating an area of the bayou guarded by a massive gate. As he explores, he realizes that the gate wasn't to keep intruders out—it was to keep something in. Immediately after this, a gargantuan snake bursts from the water and starts chasing him.