So, you're running a top-secret facility, and the first thing you did was install nearly impenetrable blast doors. Once they're closed, nothing can go through.
There is only one flaw: they take time to close. Way too much time. Sometimes it seems that the "message" to close the doors takes its time to get to all of them as well; Door #1 will start to close, then sometime after that Door #2 will start to close, then Door #3 etc.
There is some real life precedence that lends this trope some credibility. The water-tight doors on the RMS Titanic closed very slowly, with only the last foot or so dropping quickly, in order that personnel could escape the sections closed off alive. Some rather large and heavy doors also use high-torque hydraulics or electric motors to raise and lower, which are notoriously slow, having traded off speed for strength.
If they close downward, expect an Indy Hat Roll. Otherwise, people will jump or squeeze through whatever gap is still left when they reach the door, which is conveniently just wide enough.
If this is done with vehicles and the escapee is being pursued, expect the pursuers to be unable to stop in time and crash into the blast doors.
- Every example mentioned in Indy Hat Roll.
- Averted in episode 5 of Kiddy Grade. When Lumiere closes all of the doors in an enemy spaceship, they snap shut before the bad guys even realize what's happening.
- Averted in Neon Genesis Evangelion, where the internal security doors of the Geofront, once activated, snick shut instantly, sealing corridors extremely quickly.
- The door to ENCOM in Tron. Lampshade Hanging with an Ad Lib from the actor playing Flynn: "Now THAT is a big door!"
- Some security doors in the Star Wars films act this way, while others close almost instantly. Generally, whatever is required by the plot. One door on the Death Star in A New Hope was closing from all directions at once, so Han Solo had to jump through the hole in the middle.
- The first arc of the animated series Droids featured a landspeeder chase scene that used this trope, plus several others (like the Imperial Stormtrooper Marksmanship Academy) repeatedly and in quick succession. R2-D2 suggests it's a trap, and it turns out it is: Behind the last set of slow doors is a dead end and a bunch of guys with blasters.
- Spaceballs parodies the above Star Wars example, the characters jump through a door closing from the top and bottom, and are caught by the troops on the other side. However once the captain comes in behind them and asks them to turn around it is revealed it was the stunt doubles that were caught
- Terminator 3, allowing Ahnold to jump under the door and hold it long enough for John and Katherine to crawl under it.
- In WarGames, we see NORAD personnel walking in and out while a ridiculously thick metal door is closing. This is Truth in Television: The blast doors of the Cheyenne Mountain Complex are 25-ton monsters of concrete and steel, and take about 15 seconds to close. They're on record as the world's largest hinged doors.
- Played straight and averted in The One, as Gabriel escapes the Police Compound, he ducks under one of these. However, his Police Pursuers also make it through (though one of the trucks wangs its lightbar on it).
- Near the end of Entrapment: After the characters accidentally trip the security system, a wall of gates closes rapidly around them, but for some reason the door blocking the actual exit moves incredibly slowly, long enough for them to escape.
- The alien mother ship in Independence Day had a single triangular access opening that slowly closed after the heroes fired their nuke into the center of the ship. Naturally their spaceship managed to squeeze through while the pursuers all smashed into the closed door.
- In this case it's definitely justified as being slow as said doors are HUGE!
- The theater owner's bomb shelter in Matinee.
- Andromeda: The doors on the titular ship close at a reasonable pace, but the bigger, more important ones (such as onto the command center), have a design that allows one to jump through the closing door.
- Averted on Babylon 5. The blast shield closes quickly enough to protect C&C from an attack that had already been launched. Of course there's no good reason for C&C to have a window at all.
- Buffy the Vampire Slayer did the "message" version completely straight when Spike was escaping from the Initiative.
- Used on Lost: the blast doors in the Swan lower rather quickly; however, they don't all close simultaneously, which allows Locke to wedge his toolbox under the last door before it closes.
- Played with twice in the pilot episode of SeaQuest DSV. In the first case, an undersea wildcat miner is attempting to escape corporate security after he infringed on their mining fields one too many times; he pulls off an Indy Hat Roll with his mini-sub by asking his buddy at home base to start closing the docking bay doors before he's through. The trope is played straight in the second case (and re-used as stock footage several times thereafter), as a crewman is seen jumping through the main "clamshell" hatch to the titular submarine's bridge as general quarters is sounded.
- Played straight, but also Truth in Television, in Stargate SG-1. Remember those ginormous blast doors at Cheyenne Mountain? Also, the Stargate itself has been stated by Word of God to stay open as long as plot dictates, which has resulted in more than a few Slow Stargates moments over the series' run.
- Star Trek: The Next Generation: in Relics, the Enterprise-D manages to fly through closing space-doors, with the aid of a nice roll maneuver.
- Subverted for a bit of Enforced Method Acting in the Firefly pilot; Nathan Fillion and Adam Baldwin were expecting the doors to Serenity to close more slowly than they did, resulting in minor panic as Mal and Jayne jumped through the gap.
- Beyond Good and Evil has looter caves with Doors that instantly lower half-way once the spark reaches them, but slowly close past that point.
- Possible Lampshade Hanging in Call of Duty 4, where one computer controlled set of doors in one (timed!) mission open ridiculously slowly (start at 6:15):
Griggs: "Oh, you've gotta be shittin' me."
Capt. Price: "Gaz, can't you make it open any faster?"
Gaz: "Negative, but you can try pullin' if it will make you feel better."
Capt. Price: "Cheeky bastard."
- In Chrono Trigger, your team has to escape a robot factory that you've just shut down. You just squeak by the first set of Slow Doors, but Robo has to hold the second one open with his body.
- In Mega Man Zero one mission requires you to sneak into a factory. if you're detected, the Slow Door starts closing. if you're not through it before it closes, Game Over.
- The games in the Prince of Persia series are full of Slow Doors. The Sands of Time series somewhat subverts this - some of the doors close quite quickly, but can be passed using the dagger's time slowing ability.
- Averted in Dirge of Cerberus: Final Fantasy VII in a minor scene where the WRO locks down against intruders; a redundant and somewhat impractical set of doorways down a corridor slam shut in quick succession.
- In the game Dark Forces, on the level titled Gromas Mines, the player must successfully place a detonator on the reactor and escape through not one, but five slow-moving doors. The trick though is that while the doors stay open as long as the player is beyond their threshold, once he or she crosses it the doors close in a matter of seconds. If the player is caught in between one of the sections however, the doors can be reopened by a switch on the wall.
- The final level of Syphon Filter has this. You have to make it through a missile silo before the missile blasts off. There's a slowly closing blast door, and the controller has an Unnecessary Combat Roll button. Do the math.
- The Half Life chapter "We've Got Hostiles" has fire doors that take forever to close. Luckily you set them off manually, meaning you can shut them behind you and cut off the hostiles creatures dogging you. It's only one way, though, and you can't open it again if you're on the wrong side, maintaining Half-Life's proud tradition of Railroading. Even when you get to the Door to Before, the blast door you went through is securely shut.
- Used with crazy timing in Elf Quest: The Searcher and the Sword, when two elves are trying to escape from crazed trolls. What's crazy about it is that it's implied that the elves had plenty of time to escape, except that the rescue party's entrance alerts their enemies, who then check on the prisoners, see that they're gone, and trigger the trap, leaving the escapees to vault through the door at the last second. Drama! Did I mention that this is all done with giant slabs of stone a la Egyptian tomb? Read up on the thrilling escape here.
- Shows up in Molten Blade (in a government research facility, even. Talk about being underfunded). They aren't really even heavy doors.
- Parodied twice in Futurama: In the Central Bureaucracy everyone manages to make it through the door, except Bender, who just walks right through the metal. The second one is when fleeing the spaceship Titanic, when Zoidberg stops the door with only a few inches of space, forcing Hermes to limbo underneath.
- Subverted in Wallace and Gromit: The Wrong Trousers. When Wallace under the control of Feathers Mcgrew attempting to steal a diamond trips a laser beam, the chamber's vertically-dropping entrance door starts to close slowly (about 10 seconds after the alarms first go off), but instead of attempting an Indy Hat Roll, he instead immediately turns around and heads for the window - granted, he was walking on the ceiling!
- Generally blast doors weighing many tonnes are not prone to very sprightly movement. For example the doors at Cheyenne Mountain take about 20 seconds to open and close.
- Automated garage doors. Unfortunately, IR detectors take out the drama of trying an Indy Hat Roll. Fortunately, they also prevent your arm from being crushed if you are too slow pulling in your fedora.
- The extremely giant doors on the roof of the new Dallas Cowboys football stadium take SEVENTEEN MINUTES to open and close.
- The Maeslant barrier are a set of doors that can close off the New Waterway (the entry to the Port of Rotterdam) in the Netherlands to prevent flooding in the case of a storm surge. They take over half an hour to close. Not all that surprising considering the barrier is almost as long as the Eiffel Tower, and weigh about 4 times as much.
- Bank vault doors are sometimes fitted with a delay mechanism that forces anyone opening them to wait for a preset amount between activation and releasing the locks. The doors themselves open rather quickly though.
- Entirely subverted in underground nuclear testing, where specialized sensors would normally be annihilated by the blast wave of the weapon. How do you get data on how properly an atomic weapon goes off, without going with it? Massive blast doors are installed at the end of the shaft, just in front of the sensors, while the weapon itself is positioned hundreds (or thousands) of feet away. The doors themselves don't bother with simple mechanical power, and are closed shut by an explosive reaction slamming them together in the milliseconds between the initial energy front arriving at the sensors, and the thermal surge and fireball immediately following. Of course, to get it to work you need to have the doors start closing before you set off the atomic weapon, so the timing is everything - and from the nuke's perspective, at least, those are some pretty slow doors...