History Main / TwoKeyedLock

* One [[http://lparchive.org/LetsPlay/Boatmurdered/chapter1-27.html update]] of a LetsPlay of the DwarfFortress map [=BoatMurdered=] had someone submit a drawing of the employment of the "lava death system." With two keys, natch.
* One bank that [[SplinterCell Sam Fisher]] has to infiltrate in ''Chaos Theory'' has a TwoKeyedLock protecting its main vault. Fisher, however, has a remote-controlled key-turning device. In the actual game, of course, the system was activated by a simple lever.

* One bank that [[SplinterCell Sam Fisher]] has to infiltrate in ''Chaos Theory'' has a TwoKeyedLock protecting its main vault. Fisher, however, has a remote-controlled key-turning device.

* ''{{Okamiden}}'' has a ''[[UpToEleven four]]'' keyed lock in the [[SlippeySlideyIceWorld Ice Room]].

** And also in ''{{Portal}}'', though in this case it was more figuring out how to manipulate the environment with your Aperture Science Handheld Portal Device to get both buttons pressed at once so you could get through a door.

*** The logic was that warheads mounted to missiles in either ground-based stations or in ballistic submarines are secure because of the two-man-rule interlocks, and PALs would risk a loss of readiness without significant security benefit. Actual (non-trivially-coded) PALs were (eventually) applied to small warheads - air-dropped bombs and ship/air-launched cruise missiles. These warheads, unlike those for ballistic missiles, can be stored or transported in a functional or semi-functional state and thus may be lost or stolen. For these weapons, the two-man rule utilizes the PALs themselves - two officers must concur with the legitimacy of a nuclear launch order and release their portions of the PAL codes, or else the warheads cannot be armed.

* ''{{Film/Superman}} III'', to activate a satellite positioning system; although the two keys in question needed to be inserted simultaneously, not turned.

*** [[http://en.wikipedia.org/wiki/Permissive_Action_Link Permissive Action Link]]. Under the [[JohnFKennedy Kennedy administration]], somebody decided to put [=PALs]= on the US nuclear arsenal to prevent unauthorized firing. SAC objected to this practice, fearing the possibility that the launch codes would not be available in time of need. So, very quietly, SAC installed these devices, intended to ensure the safety of the free world, and very quietly, they set the combination on every single one of them to [[{{Spaceballs}} 00000000]]. Very trusting people, SAC.

* ''{{Superman}} 3'', to activate a satellite positioning system; although the two keys in question needed to be inserted simultaneously, not turned.

** A two key (Two combination in the book) system was also used on a safe in the submarine that contained the mission orders and code books.
* Used to shut down [[spoiler: honey production]] in ''BeeMovie''.

* The movie ''CrimsonTide''. Two keys needed to unlock the missile launch controls. The XO refuses the Captain's orders to unlock the controls because they lost communications before the launch order was confirmed as protocol demands. Mutiny ensues.

* The JamesBond film ''{{GoldenEye}}'' had this for the titular weapon as well. [[spoiler:Interestingly, this was replicated in the secret underground base as well.]]

* In the ''MassEffect'' novel, ''Ascension'', Hendel and the one of the Quarians had to this to a bomb that is rigged to explode and destroy a ship with a crew of over 500. With the added problem that they couldn't see each other.

** The Xindi [[EarthShatteringKaboom planet killer]] required access codes from any three of the five members of the Council in order to fire. This would've been a useful feature [[spoiler: when three (and eventually four) of the Xindi races back out of the plan to destroy Earth. Unfortunately, the reptilians had ways around the codes.]]

** Once on ''{{Stargate}}'' a possessed O'Neill tells another guy at gunpoint to insert his key, which struck me as defeating the purpose - you'd think they'd tell the people with keys to die rather than be coerced.

* In the 2000s ''BattlestarGalactica'', the nuclear launch tubes on battlestars are controlled by two-keyed locks.
* In the {{Andromeda}} pilot episodes, Dylan gives four people he barely knows positions on his ships - because, apparently, one person cannot launch the Nova Bombs.

*** [[http://en.wikipedia.org/wiki/Permissive_Action_Link Permissive Action Link]]. Under the Kennedy administration, somebody decided to put PALs on the US nuclear arsenal to prevent unauthorized firing. SAC objected to this practice, fearing the possibility that the launch codes would not be available in time of need. So, very quietly, SAC installed these devices, intended to ensure the safety of the free world, and very quietly, they set the combination on every single one of them to [[{{Spaceballs}} 00000000]]. Very trusting people, SAC.

* One [[http://lparchive.org/LetsPlay/Boatmurdered/chapter1-27.html update]] of a LetsPlay of the DwarfFortress map [=BoatMurdered=] had someone submit a drawing of the eployment of the "lava death system." With two keys, natch.

* Used [[http://www.goblinscomic.com/d/20090103.html here]] in ''{{Goblins}}: Life Through Their Eyes'', with a four-key system. [[spoiler: [[CuttingTheKnot A giant just smashes the door open for them]], because they REALLY don't have time for puzzles.]]

* On ''TheSimpsons'' two keys were required to be turned simultaneously to drop the "perfect 300 game" balloon at the bowling alley.

* ''WarGames'', to blow up half the planet ("TURN YOUR KEY, SIR!").

* ''{{Ratchet and Clank}} Future: A Crack in Time'' includes a variation of this. Clank must use his newly-acquired [[spoiler: ability to shift time]] to record multiple copies of himself completing various tasks (such as pressing buttons or activating platforms), usually with the end goal of opening a door at the end of a room. The actions of the copies must be perfectly timed in order for the player controlling the "real" Clank to solve the puzzle; with up to four copies working at once to complete the task, the difficulty can ramp up pretty quickly.

* ''{{Skies of Arcadia}}'' has an odd one. A whole dungeon focused around locks that require two people to stand on panels in different parts of the dungeon, the thing is neither side knew that they were helping each other get past and they just both happened to be searching for the same treasure at the same time.

* The Fire Temple's inner sanctum in ''[=~Avatar: The Last Airbender~=]'' could only be opened by five simultaneous fireblasts. A single sufficiently skilled Firebender ''could'' do all five at once, but in most cases it took five people.

* The LordDarcy story ''A Case of Identity'' had a two key system for a vault containing the Marquis' official regalia. The door had eight keyholes and two keys. Each man with a key knew which keyhole to use his key in, but not which keyhole the other key went into. Improper timing, or turning a key in the wrong hole, would set off the alarm.

** A two key (Two combination) system was also used on a safe in the submarine that contained the mission orders and code books.

** In the novel, it is stated that five officers are needed to carry out a launch.

* Used as an annoying minigame in ''FinalFantasyVII'', where to open a security door two party members must push two widely separated buttons at the same time. Doing so involved involved pushing the X button and hoping to hell you got the timing right.

* Any game that focuses on cooperative play will have something like this.

[[folder:Anime and Manga]]

[[folder:ComicBooks]]

* The nuclear missile locks in ''{{The Hunt For Red October}}'' apparently had one of these. Although we never see the locks themselves, we see Captain Ramius taking possession of both keys -- which, as the doctor points out, sort of defeats the point.

* The JamesBond film ''{{Goldeneye}}'' had this for the titular weapon as well. [[spoiler:Interestingly, this was replicated in the secret underground base as well.]]
** [[spoiler: Well, you don't want Boris setting it off early.]]
* The ''USS Enterprise'' [[SelfDestructMechanism self-destruct sequence]] needed spoken confirmation from three senior officers to trigger in ''StarTrek III''.
** That destruct sequence is taken verbatim from the infamously {{Anvilicious}} TOS episode, "Let That Be Your Last Battlefield." [[ThePasswordIsAlwaysSwordfish Twenty years later, they still hadn't changed the codes.]]
** In TNG, it's often the Captain and Executive Officer, so the "two senior officers" may be in lieu of the XO in the event that they are unavailable. The Enterprise-E was slated to self-destruct on confirmation from Worf and Crusher since Riker was unavailable at the time.

* An escape hatch in ''ThursdayNext: First Among Sequels'' has two handles which need to be turned simultaneously.[[spoiler: In a touching Redemption Equals Death, Evil Thursday chooses to help Thursday escape, knowing that she herself has no way out.]]
* In the ''GearsOfWar'' Novel, ''Jacinto's Remnant'', Chairman Prescott, Colonel Hoffman and somebody else had to insert three keys and turn simultaneously to activate the Hammer of Dawn technology that destroyed most of the planet. Prescott had it next to his car keys.

[[folder:Live Action TV]]

* Rare example not involving nukes: in an episode of {{Alias}} set in a Romanian mental hospital, the door to get out is double-keyed, one lock on the wall to either side of a wide maintenance door, too wide for one person to turn both keys with their hands. [[spoiler:Sydney deals with this by acrobatically turning the other one with her foot.]]

* Happens all the time in ''GearsOfWar 2''.

* ''SkiesOfArcadia'' has an odd one. A whole dungeon focused around locks that require two people to stand on panels in different parts of the dungeon, the thing is neither side knew that they were helping each other get past and they just both happened to be searching for the same treasure at the same time.

[[folder:Webcomics]]

* The Fire Temple's inner sanctum in ''AvatarTheLastAirbender'' could only be opened by five simultaneous fireblasts. A single sufficiently skilled Firebender ''could'' do all five at once, but in most cases it took five people.

<<|MilitaryAndWarfareTropes|>>

* In episode 13 of ''NeonGenesisEvangelion'', an Angel infiltrates NERV's computer system, and Aoba and Hyuga have to do this in order to cut the power to the MAGI supercomputer. It doesn't work.

* The lab where the extremis samples were kept in ''IronMan: Extremis''. This was a key plot point.

* Apparently, the final PowerLimiter placed upon [[PersonOfMassDestruction Hayate Yagami]] in ''MagicalGirlLyricalNanoha [=StrikerS=]'' had to be removed simultaneously by [[TheBrigadier Admiral Chrono Harlaown]] and [[GoodShepherd Knight Carim]], making it a TwoKeyedLock even though they didn't have to be physical present near Hayate at the time.