Something important is locked. There is a key. However, this key is inside. You need the key to reach the key.
While this trope can be Played for Laughs with trivial situations such as locking your car keys in the car, many works that use it choose to employ it in a far more dramatic manner. The hero is on a quest to find the key, eventually finding some other way to reach what he needed the key for—and then he finds out that his initial quest was futile; the key was inside all along.
In a video game, this can be used to create a Door to Before.
If The Key Is Behind And In The Lock, one possible solution is the Paper Key-Retrieval Trick. Otherwise Hairpin Lockpick, Skeleton Key Card or Shoot Out the Lock may help to resolve the problem.
Subtrope of the Catch-22 Dilemma. Compare Bragging Rights Reward. If the real question is not how to open the door, but how whoever locked the door was able to leave the key there in the first place, it's a Locked Room Mystery.
- In one episode of Cardcaptor Sakura, Tomoyo has been trapped in a classroom as Eriol messed with the floor plan as a test for Sakura. Sakura needs to find her, and Syaoran says he has a magical technique that can locate lost people, provided she has left an object behind. (Not unlike a dog using scent, except it works off auras/energy signatures.) Tomoyo did have an umbrella...but it's with her in the very classroom they're trying to locate. The actual solution, which Sakura eventually figured out, was to convert the Shadow card and use its power to seek Tomoyo's shadow, following it as it went.
- In the third episode of Cowboy Bebop this is played straight. The only way to decrypt the special decryption program is with a cypher key that was itself encrypted, and only the protagonists know where the key is.
- Played for Laughs in Yuri is My Job!. The main character, Hime Shiraki, is a girl who wants everyone to love her. She ends up working at a salon where the employees roleplay as members of an all-girls school, and takes part in the Blume elections, in which one student is chosen as "Lady Blume," to represent the school, and is given the privilege of making a decree. Hime considers asking for everyone to love her, but since the Blume title is decided by popular vote, Hime's friend Kanoko thinks, "Hime-chan, that's already what being Lady Blume means!"
- Played for Laughs in YuYu Hakusho. At the start of the Chapter Black arc, Kuwabara, Botan and Kurama are searching for Hiei, since Yusuke's been kidnapped and those responsible want the four of them to come to the hideout. After the group realizes that their tools won't help find Hiei, Botan laments that Hiei isn't here, or else he could find himself with his Evil Eye.
- An Achille Talon story has an emergency phone protected behind a glass that must only be broken with a hammer that is also behind the glass. This causes a breakdown to the policeman who wanted to use it, while another character attempts to comfort him by saying it probably prevents a lot of hammer thefts.note
- Disney Ducks Comic Universe:
- In the Donald Duck story "Sagmore Springs Hotel," Donald, as a Hotel Manager, accidentally locks the combination to the hotel safe inside the safe. In his attempts to open it, he ends up devastating the entire hotel and destroying his uncle's important cheque.
- Another story had Magica DeSpell tracking down the ingredients for a spell that will enhance her magical abilites to unstoppable levels. After getting run ragged tracking down various rare ingredients, she discovers the last ingredient is... the most prized possession of her worst enemy. Which just happens to be Scrooge McDuck's #1 Dime, and she needs the potion to get the dime in the first place. Poor Magica throws a fit and gives up on making the potion.
- Another story had one of Magica's attacks prompting Scrooge to buy the world's most impregnable safe to keep the Number One Dime, only for the combination to be accidentally destroyed. Since Scrooge wants to be able to see the Dime on occasion, he and Donald go to the ends of the Earth to track down the world's greatest safecracker to open it. He succeeds, gives Scrooge the combination, and leaves. Cue Magica attacking again and the door of the safe to slam shut...with the new combination inside. Cue the three crying and banging on the door. The End.
- The Incredible Hulk: Amadeus Cho is a super-genius character in Marvel Comics who, however, needs high-sugar junk food for his brain to function properly.
- In one issue of The Incredible Hercules he is kept prisoner in a society where the only junk food is locked in a vault (long story), and his intelligence is faltering. He manages to reach the vault and says "After I eat the food inside I'll be smart enough to figure out how to open the vault", and only then realizes the flaw in his plan.
- One strip of The Far Side had a pair of aliens trapped on Earth. As a crowd of curious humans approaches them, one of them says to the other "Well, here they come. You locked the keys inside, you do the talking."
- Legendarily Popular: Team Galactic has just managed to open the Spear Pillar when Ash arrives, and they promptly hide their equipment and evacuate. Ash, not realising they were there, consults with Giratina and decides it's best to just lock up the pillar (since it's meant to be off limits to everyone), assuming that Arceus got confused and left it unlocked after the Michina incident. Team Galactic's leader then learns that the Spear Key was amongst the equipment left inside.
- Rocketship Voyager. In the middle of a raging battle, B'Elanna Torres finds herself having to get through an air-lock hatch whose locking handle has been wrenched off, with the latches all on the inside. She disconnects the electromagnets used to clamp the docking tunnel onto another spacecraft, and places them around the hatch mounting so their magnetic field pulls open the latches.
- Destiny's Divide:
- The system meant to drain the underground lava pools away from the lightstone cavern in Onu-Koro malfunctions when a build-up occurs and no one is able to clear it, creating a lava river cutting off the cavern and causing a lightstone shortage. The problem is that Nuparu put the panel to control and fix it on the side of the cavern, on the logic that any workers trapped in the cavern in such a scenario would need a way to get out, but neglected to consider what would happen if no one was in the cavern. Another Onu-Matoran named Damek lampshades this once Penny summarizes the situation, telling her and Takua that he'd pointed out that the panel should have been on the other side, or that there should have at least been a redundant panel, but no one listened to him.
- Gali notes that Makuta, with his twisted sense of humor, seems to like setting up scenarios like this with the masks, putting them in places that would be easy to reach... with said mask, like putting her Mask of Levitation on top of a large cliff, seemingly anticipating how the Toa would fail to work together properly.
- In The Simpsons Movie, Prof. Frink has invented a drill that could cut through the dome and free them all. "It's right there, out... side the dome."
- In Ron's Gone Wrong, the main reason for the titular Ron's glitches are that he lacks access to the Bubble network for B-Bots due to damage sustained when he was being taken to the shop. Technically it is possible to program Ron to manually access the network, but since the instructions for doing so are on the network...
- In the first Back to the Future movie, Marty is thrown into a car trunk by Biff's goons. The car belongs to one of the members of the band that was playing at the dance, who chase them off. The band tries to get Marty out, but the keys are in the trunk. This becomes a plot point later when the band manages to free Marty, but the guitarist slices his hand as he does it, forcing Marty to take over at the dance.
- Played for Drama in The Bourne Legacy. When one of the scientists locks the door to a top secret lab and starts shooting his colleagues, an armed security guard responds, only to be told that everyone who knows the access code is already in there with the killer. By the time another guard arrives with a master key, everyone's dead except for a Sole Survivor.
- Early in Dark City, John Murdoch goes to an automatnote to retrieve his lost wallet. One of the cooks places John's wallet into one of the food windows, meaning John has to pay a small fee to open the window and get his wallet back—which John can't do because all his money is on the other side of the window, in his wallet. Desperation over the impossible situation triggers John's latent Tuning power, and he breaks the lock with his mind to get his wallet back.
- In The Hugga Bunch Made-for-TV Movie, the villainess, Queen Admira, stays young by eating young berries, which grow on a tree she keeps locked under a glass dome. When the heroine comes to take some young berries for her grandmother, Admira catches her in the act. In her hurry to leave, the heroine accidentally leaves the key for the dome on the ground by the tree, and as the dome descends, Admira lunges toward the key, but is too late.
- Jupiter Ascending: Jupiter runs headlong into a wall of bureacracy when attempting to claim her title, because she doesn't have any appropriate documentation of her identity — but without it, she isn't able to fill out the paperwork to get that documentation. Eventually her advocate bribes a bureaucrat to sign off on her identity paperwork.
- In Little Monsters the heroes are trapped in a locked room by the villain. After MacGyvering a way for Maurice to be reduced to a pile of clothes and slid under the door, once on the other side he says:
Maurice: Any of you freaks know how to pick a combination lock?
- Although he's simply joking and opens the door a second later.
- In the Joss Whedon version of Much Ado About Nothing (2012), Nathan Fillion, playing the fuzz, has this happen to him.
- This exchange from Spaceballs:
(Guard shoots the lock on the Winebago)
Dot: Open the door!
Barf: I can't, the lock is fused!
Vespa: What about this door?
Barf: Its locked!
Vespa: Where are the keys?
Vespa: Oh great!
- In Up the Chastity Belt, Nick the Pick is called in to unlock Lobelia's chastity belt. However, all of his tools are in his toolbox, which is locked. And he can't find the key. The rest of film shows his increasingly desperate attempts to open the toolbox.
- This moment happens in The Whole Ten Yards.
Lazlo: You locked my son in the trunk?
Oz: No! No, sir. He locked himself in the trunk.
Lazlo: [pause] This I believe.
- World War II. Hitler hears of the Staff of Moses, which can make the seas part. If the Germans can get their hands on it, they can invade England by land. Where is the staff? In the British Museum.
- A fairly standard situation in the Locked Room Mystery is for the police to have to break into the Locked Room, because the key is inside with the deceased.
- In Blĺ Tornet, the Guardian has been sleeping on the High Altar for over a thousand years. There are a lot of prophecies about how a chosen one will one day wake him. In the meantime, one of the worst blasphemy someone can do is to touch the Guardian's holy sleeping body. It turns out that they artifact needed to wake the Guardian is in fact inside the altar: Only a blasphemer can heal the horrible wrong that happened so long ago, and lead the civilization back on the quest the creators had originally intended.
- There's a recurring gag in Thief of Time about "opening the box with the crowbar you will find inside". The solution is get some help; in the literal example early on, Igor is inside the box with the crowbar and hands it to Jeremy through the slats.
- In Jingo the Bursar has locked himself in the Unseen University safe and taken the key with him. "It's not even as if there's a keyhole on the inside".
- In Going Postal, Vetinari plays mind games with condemned criminals—if they use the spoon they get with their gruel to try and dig a stone block out of the wall as part of an escape attempt (ruining the spoon in the process), they finally pull the block out only to find a little alcove behind with a shiny new spoon in it.
- Guards! Guards! has an interesting example. Vetinari is locked in the dungeon by Wonse after the dragon becomes King, and when Vimes manages to break in and find him, he realizes that the dungeon has a complicated locking mechanism on the inside so that Vetinari is, at that moment, the safest person in the city. He also, of course, has a key to the dungeon, and promptly uses it once the dragon is defeated.
- Dragon's Egg: When the science and technology of the neutron-star dwelling Cheela develops far beyond that of humans, they send humans an encyclopedia... with entries encrypted with keys based on the new knowledge. For instance, the encryption key for the knowledge behind Faster-Than-Light Travel is engraved on an object in another star system. Thus, humans have to advance by their own efforts, but will be able to verify the answers and perhaps learn additional details when they do.
- Insert Knob A in Hole B: The machine that can correctly put together the components of any device, is disassembled into its components for shipping.
- Towards the beginning of the Lord Darcy novel Too Many Magicians, Master Sorcerer Sir James Zwinge is in apparent distress in his hotel room. But he'd enchanted the lock to his room so that only one copy of the room key could open the lock - his personal copy, which was with him in the room. The people responding to his call for help had to smash a hole in the door with an ax to get inside, by which time he'd bled to death.
- A Song of Ice and Fire: As it turns out, to solve a prophecy about how to get dragons back into the world so you can be very powerful through controlling them again... you kind of needed to remember enough about how to incubate dragon eggs, first, to understand what the hints in the riddle were likely to be blathering on about to spot which circumstances would help to hatch them successfully. Easy. Not. Some, like Aegon V, tried brute-forcing the thing using overwhelming power (lots of Greek Fire) and some best guesses: it failed. Others might have tried to be sneaky chessmasters (looking at you, Bloodraven) trying to move people and circumstances into likely positions — to then get burned by the unexpected consequences of getting the code a little wrong back-blasting them. Alternatively, you could just totally luck out by hitting on the actual combination randomly without meaning to solve the thing... as Daenarys has. She doesn't seem to even know that a full prophecy exists, although she might still know some of the info it had in it. Problem is, once successfully incubated and hatched, you then also need to, you know, find a way to direct and the control your dragons, since how to train them has also been lost to the mists of time. And, there's only one way to learn, now: playing with fire by trial and error. Which a lot of people will be very unlikely to be willing to let you do, so will have hidden or destroyed pieces of information you would have needed to get to this point in the hopes of stopping you getting to the dragon-riding stage in the first place... Um. No wonder the Targaryens repeatedly hit problems with trying to force that prophecy open with the equivalent of either a crowbar or lockpick...
- A variation in Star Corps Agent. The protagonist gets his hands on a box his partner was killed for. He can only guess what's inside. Possibly a way to get advantage in the war with the Radnits. But would it help him get off the hostile planet alive to deliver it to Earth? It could be a powerful handheld weapon that he could use to shoot his way through the spaceport cordon. Or it could be designs for a ship part, which are utterly useless to him at the moment. But the box is of a type that can only be locked from inside, which means that if he opens it, he won't be able to use it to barter for a way off the planet. He ends up opening it anyway and finds a genetically-engineered symbiote that turns him into a Super (normally, Supers are born). He swaps the symbiote in the box for his disguise symbiote, then uses telekinesis to lock the box from the inside. The Radnits scan the box and detect a symbiote, so they let him leave.
- Subverted in "The Talking Stone" by Isaac Asimov, where people are searching for an uranium asteroid an illegal miner found, and due to the miners dying in an accident, all they have is a statement by a silicon based alien that the coordinates are "on the asteroid" (the alien died right after saying that). In the end it turns out that the alien wasn't particularly up to date in astronomy, and the coordinates were actually on the ship - hidden among the registration codes of the equipment.
- When humanity starts reverse-engineering alien technology in Troy Rising, their Artificial Gravity prototypes are clunky, prone to lethal malfunctions, and flies to pieces under anything but the lightest use. By the time they discuss this with Tyler Vernon, the scientists have worked out that the only tool capable of making an efficient gravity generator is another efficient gravity generator.
- In the Black Books episode "The Big Lockout" Manny bought a security system. It was very simple, you press 05 to arm it and then when you go out it will lock automatically. And then when you come back in, you punch in the code and the lock will open. Bernard quickly points out the slight problem with this that if the door's locked, he can't get in to punch in the code to open the door. As it turned out, Manny didn't know the code anyway.
- In an episode of Caroline in the City, Del and Charlie get trapped in Del's car due to a snow plow and Charlie accidentally locking the keys in the trunk instead of an ice scraper.
- An episode of Cheers had Woody trying to install a VCR when someone handed him the instructional video that came with it. Woody of all people incredulously asks, "We hook it up. . .and then we watch the video on how to hook it up?!"
- Parodied in a 2011 episode of The Colbert Report. While discussing cloud storage, Stephen proclaims he stores all his information in the cloud, including info needed to answer the security questions when forgetting his password to the cloud.
- Corner Gas:
- Hank had a lockbox with a combination lock. One of the things inside the lockbox was a notepad where he wrote down important stuff he needed to remember... such as the combination to the lock.
- Hank once locked his keys in his truck. He had a great deal of difficulty trying to unlock it with a coat hanger, until Davis passed by and notified him that his passenger-side window was open.
- One episode of Fraggle Rock had Doc and Sprocket acquiring a locked trunk and spending the entire episode trying to get it open. When they finally do, all that's inside is the key.
- That happens in an episode of Get Smart too, regarding the wall safe in the Chief's office.
Chief: Have you got the new combination, Max?
Max: New combination?
Chief: Yes, according to standard security procedures we changed the combination yesterday. Do you have it?
Max: Well, I didn't memorize it, but I had the usual three copies made.
Chief: Where are they?
Max: I burned them.
Chief: Oh, yes. Of course. Do you have the Master Copy?
Max: No I don't, Chief. But I put it in a place where no one will get it.
Chief: Where, Max?
Max looks at the wall safe.
- On two separate occasions on I Love Lucy, Lucy gets locked in a meat freezer and a steamer trunk. Both times, she has the key to the lock.
- In one episode of the children's magazine show Jigsaw, the cast were given a telephone with which to summon the OO Men for their Once an Episode appearance. The telephone was in a sealed, glass-fronted cabinet, so there was also a hammer to break the glass. The hammer was inside the cabinet. Subverted when this was pointed out to the OO Men, and they explained that it was perfectly simple — the cabinet wasn't sealed after all. You opened it, got out the hammer, closed it again, and used the hammer to smash the glass.
- Happens to MacGyver (1985) on occasion. The second episode of first season had actually Mac Gyver in a room which was locked from outside with key still in door. MacGyver, being MacGyver, puts a map through the space under the door, then puts his knife to the lock to push key out of it so it falls on map, with which he then pulls it in.
- Vincenzo: In episode 13, as Vincenzo and Young-woon hurriedly cover their tracks after exiting the vault full of gold, Vincenzo chucks Young-woon's coat into the vault. Afterwards Young-woon has to deliver the bad news that the biometric data they need to access the vault was in a pocket of the coat.
- Young Sheldon: In "Little Green Men and a Fella's Marriage Proposal", Georgie and Mandy lock the keys in the car while CeeCee is inside.
- Unwinnable games of Freecell, where the cards you need are locked underneath cards you can't move anywhere.
- Unwinnable layouts in Mahjong Solitaire result when needed tiles are trapped between tiles that can't be accessed without them.
- Yet another of the many ways the GM can make your life miserable in Paranoia. You're given a useful piece of tech, but if you use it wrong, it will blow up and kill you. Where's the instruction manual? That item is above your clearance level, citizen.
- This is basically what makes some deals of Solitaire unwinnable. If the cards onto which you'd need to move a face-up card all happen to be face down behind it, then they might as well be keys on the wrong side of a locked door.
- In 13 Sentinels: Aegis Rim this trope is frequent due to the emphasis on POV switching: each POV character has two or three plot locks, some of which require to have played through another character's story in order to unlock... and the former's next plot lock could be tied to another event in the latter's story. The most egregious example is Takatoshi Hijiyama's final plot lock, which requires to have viewed an event in Renya Gouto's story... which requires you to have all other characters, including Takatoshi himself, at 80% story progress at least. Luckily for you, when Takatoshi locks, he's already at 80%.
- In Adventure, on the hardest difficulty, the items were distributed in a kind-of-random manner, which occasionally resulted in the gold key being locked in the gold castle. Despite entering the gold castle being a necessary step in completing the game (the last step, in fact), this did not make the game unwinnable, as sooner or later the bat would fly in and take the key out.
- Ancient Domains of Mystery: There's an intentionally useless item called the scroll of cure blindness. You can't read scrolls when you're blind. (It has some other, more creative uses, however.)
- Banjo-Kazooie: In Gruntilda's Lair, the Jiggy pertaining to Bubblegloop Swamp's Witch Switch is in a barred cavity within a large statue of Gruntilda herself. Hitting that Witch Switch does not open the bars, it instead blows open the cone part of the statue's hat, revealing a hole. You must then drop down into the hole from the floor above in order to reach the Jiggy. Upon collecting the Jiggy, the bars will open, allowing you to escape.
- Banjo-Tooie: When you first enter Grunty Industries, the front door to the factory will be locked, preventing you from making any significant progress in the level. However, if you search around a bit, you'll find the switch that opens up the factory's train station. While the station is inside of the locked building, you can leave the level, backtrack to another train station, then ride the train into the station inside Grunty Industries. As you explore the factory, you'll eventually be able to open the front door from the inside.
- BioShock: the head dentist has been killed and thrown through his office window, and the only way to get in is to use the Telekinesis Plasmid to get his key off the wall behind the window.
- An early sidequest in Borderlands: The Pre-Sequel! requires you to overload an electronic safe that the owner has lost the password to, in order to force it open. Turns out she put the password in the safe.
- Castlevania: Symphony of the Night: The Mist transformation is found behind bars that gives out the message "Mist could pass", requiring you to loop around Colosseum so that you can get to the transformation from the other side.
- Dragontorc: The key to open two locked doors in the Sanctuary of Halgor is in Halgor's tomb, behind one of the doors, so the player needs to find alternative means to get to it.
- Dwarf Fortress: Embarking without an anvil walks the line between Self-Imposed Challenge and Unintentionally Unwinnable. You need an anvil to forge anything out of metal, and anvils can't be made out of anything else. But you can buy one from a merchant caravan that will show up in a few in-game months.
- It is common in The Elder Scrolls III: Morrowind to find keys to the various doors of a dungeon or secure building in the farthest reaches of that locations. Downplayed in there is still value in finding the key, as it can unlock other optional areas within as well as sometimes chests or other containers, saving you the trouble of picking the locks or using spells to open them. A prime Justified example (with one notable quest-related exception) are the Great House vaults in Vivec. In most cases, the only keys are carried by the Ordinators standing guard within the vaults, meaning you will have had to pick the locks to get inside and the key is now useless to you. Justified for them, however, so they can come and go.
- Escape Simulator: A variation occurs within the first Omega Corporation room; a post-it note on a briefcase states that the combination to it is on a bracelet... that is currently inside the case. The solution to obtaining the code is by putting the case in the metal detector.
- In La-Mulana 2, the Corridor of Blood functions as a back door into areas that are initially locked off. In at least one instance (Eternal Prison), this is required to retrieve an necessary item to unlock the area's front door.
- The Legend of Zelda:
- In A Link to the Past, there's one locked treasure chest whose only key, you are told, is inside the chest, and you can never open it. Fortunately you can drag it with you until you find a master lockpicker.
- In A Link to the Past: Randomizer, the randomizer logic explicitly averts this; but the more recent versions make an exception for the specific cases where a Small Key is the only thing behind an ordinary lock. Also, in the two dungeons note where the Big Key isn't required to reach the boss (or any other chest), the Big Key can be locked inside the Big Chest, since it doesn't prevent completion of the game.
- Link's Awakening:
- An Unintentionally Unwinnable example in Angler Tunnel: the door one particular Interchangeable Antimatter Key is meant to be used on has another behind it, but by making a tricky jump it can be used on a different door that doesn't have a replacement behind it.
- Played with in the Key Cavern, also averting Permanently Missable Content. A hub room in one part of the dungeon has four locked doors. Three of them are dead ends that also contain a key (which can be used on one of the remaining locked doors), while the fourth allows the player to proceed (but does not give the player a key, so the other doors accessible from the hub remain locked). Near the end of the dungeon, an extra key can be obtained to access any locked rooms the player hadn't entered.
- The Minish Cap: Talon lost the key to Lon Lon Ranch, and the spare key is inside the house. The solution is to shrink down to Minish size, enter the house through a small hole, pick up the key inside and bring it to him.
- Skyward Sword:
- Defeating the Stalmaster in Skyview Temple will award you with the Beetle. However, the door to the room will not open upon defeating the Stalmaster, as it can only be opened via the switch outside. To escape, you must send the Beetle through a raised hole in the wall and hit the switch with it.
- At one point in the Ancient Cistern, a key is held by a Mook on the other side of some bars. The solution is to use the whip to grab the key.
- Breath of the Wild:
- The shrine containing the bomb rune is surrounded by walls, and the gate is blocked by a giant rock that can only be destroyed by... bombs. It serves as a reminder to players of previous Zelda games that in this one, just climbing over the wall is a viable option.
- A shrine has a literal example, where a chest containing the key you need to get into a cell is inside the cell. The solution is to shoot a burning arrow through the cell's bars into the chest, which is made of wood. Once the chest burns up, you can use the Magnesis rune to pick up the key.
- The upper reaches of Death Mountain are so hot that Link will catch fire the instant he enters the hot zone, and rapidly start losing health as a direct consequence. Fireproof Elixirs, which negate this effect, can be bought at Eldin Ranch or off of Goron merchants at lower altitudes, but the very nature of the game means you could very well not approach from that direction, and even then the elixirs don't last forever (though one Fireproof Elixir is enough to get you to Goron City, and three will last you long enough to do some exploration in the process). Fireproof Lizards and Smotherwing Butterflies exist to make more elixirs, and Flameguard armor can be bought in Goron City to protect from the extreme heat... and both are found in the ultrahot parts of Death Mountain. You can circle around to approach from the south, or you can cook enough food to feed all of Hyrule and chomp on it until you get to Goron City. As a bonus, the armor merchant freaks out if you talk to him without active flame resistance.
- Similarly, while still on the Isolated Plateau, you need frost resistance to get to one of the shrines. You can either learn how to craft frost resistance food at this early stage, and also receive a frost resistance armor as a reward, or if you can manage to make it all the way to the highest point in the cold zone (by building lots of camp fires along the way, carrying a torch whenever you've got a free hand, and eating food to heal whatever hearts get lost) the Old Man will reward your tenacity with the same piece of armor.
- In Mega Man: Maverick Hunter X, Vile unlocks different types of weapons as he defeats bosses, and for the most part he has at least one that's equivalent to each of X's weapons. Defeating Armored Armadillo unlocks Energy Ball weapons, including Peace Out Roller (Vile's equivalent to Electric Spark)... which is Armored Armadillo's weakness. While he's also weak to some of Vile's Rocket Punch attacks, none of them can destroy his armor the way Peace Out Roller can.
- In the NES port of Metal Gear, the keycard required to enter Building No. 4 is inside the building itself. This requires Snake to get captured on purpose in order to get inside said building.
- A similar situation occurs in Snake's Revenge when the player reaches the entrance of the first enemy base. Only this time it's one of Snake's comrades who allows himself to get captured, so that Snake can sneak in undetected.
- The Metroid series uses this extensively for things like Power Bomb capacity upgrades, hiding them behind a door or wall that requires a Power Bomb to open.
- In Might and Magic V, the key to the Western Tower is inside the Western Tower. You're supposed to go into the Western Tower through the Skyroad entrance, which isn't locked, to get it.
- The first level of Mystery of Time and Space has the key in the keyhole on the other side of the locked door. To get it, you have to slide a poster underneath the door and then push something small enough through the keyhole to make the key drop onto the poster, which you can then retrieve.
- Paper Mario:
- In Toad Town, there is a locked house that you cannot enter. However, once Sushie joins your party, you can reach a pipe in the Toad Town Tunnels that will lead you into the house. Inside is the key.
- When you first meet Bombette, she is locked up in the dungeon at Koopa Bros. Fortress. As there is no door to the cell, you need to travel to the floor above and trigger a trapdoor that will drop you into the cell. Fortunately, Bombette will join your party at this point, and you can use her ability to blast through the wall. Bombette will then realize that she could broken out sooner if she had actually thought to do so.
- The Super Hammer is located in a small room in Dry Dry Ruins that is sealed off by a stone block, although you'll need the Super Hammer in order to break the block. Fortunately, it is possible to fall down into the room from a higher point, grab the Super Hammer, smash the block and the leave.
- The Ultra Hammer is located behind a metal block inside Mt. Lavalava. Similar to the above example, the Ultra Hammer is needed to break the metal block. Instead, you need to solve a small block-pushing puzzle and take the long way around in order to reach the Ultra Hammer. From there, you can break the metal block as a shortcut out of the room.
- Paper Mario: The Thousand-Year Door:
- In Creepy Steeple, the room that the parrot is in is locked; the only way in is via a secret passage. Upon entering the room, you can find the key that will unlock the door, which is crucial, as you are unable to go back through the secret passage.
- The Ultra Boots are located behind a wall of boxes in Riverside Station. As the wall is too high to surmount, you must find another path that will lead you around to where the boots are. Upon obtaining the boots, you can jump up to a pipe and shimmy across it to bypass the boxes.
- In Persona 5, during the infiltration of Madarame's Palace, the group finds a door that is guarded by a laser barrier, and a sign helpfully points out that the laser beams can be disabled in a control room on the other side of the barrier. Luckily, they have a way to get in: since the door matches one in the real Madarame's house, Morgana picks the lock so that Madarame witnesses it being opened, thereby changing his cognition that the door is unopenable and resulting in it being opened in the Metaverse. At that point, the protagonist and Ryuji take advantage of the window of opportunity to go inside and reach the control center so they can deactivate the beams.
- From a gameplay perspective, the only way to unlock the ability to read two chapters at once requires a lot of effort. You need to unlock Jinbocho, and purchase and read "Master Swordsman," "Call Me Chief," and "Reckless Casanova" (which are the only books that take three sessions each to read) before you can buy the "Speed Reading" book. Once you read that book, you can read all the others in one night, but since all other books require one or two sessions to read without the book, this ends up being an Awesome, but Impractical perk. Royal averts this by allowing you to obtain the "Speed Reading" book for free from the school library, starting in July.
- In Pokémon Platinum, the only way to obtain Regigigas is to have all three of the other Regis... which can only be obtained by getting a Regigigas through events! The only other way to get them (and the only way to get Regigigas period in Diamond and Pearl) is to transfer them from the Generation III games.
- Invoked & defied in Quest for Glory V. Your room at the inn has a storage chest, and you can put your room key in it. However, you cannot keep the key there: The narrator will go on about how you "realize your mistake", and the game will automatically make you take your key back. This mechanism is still in place after you install the "mystic magnets" that will let you teleport into your room (without the key) whenever you want to.
- Ratchet & Clank: Going Commando has a similar circular version. On one planet there is a wrench upgrade in a glass case with a "use wrench to break glass" note attached. Nearby in another glass case there is a rock with a "use rock to break glass to get wrench to break glass to get rock" note. As Clank tries to figure out the puzzle, Ratchet just smashes the wrench's case with his current wrench and takes it.
- The Interactive Fiction game Savoir-Faire has one locked door where you can see the key through the keyhole. The solution to unlocking this door is more creative than the usual ones, due to the game world's Functional Magic which lets you "link" similar things to each other so that doing something to one of them will similarly affect the other: link the key to your sword (it's ornate enough to allow the link) and then turn your sword in its sheath. Voila, an unlocked door!
- Starship Titanic has two, one that you have to resolve and one that you have to avoid.
- The first is a circular version — in order to obtain a hammer, you need to press a button with a long stick. However, in order to retrieve the long stick, you must break the glass covering it with a hammer. Fortunately, there's a parrot perch that is sufficiently long to press the button and retrieve the hammer.
- The second example makes the game Unintentionally Unwinnable if you trigger it. When you first pick up the parrot, it escapes after a few seconds and gives you a feather, which unblocks the Mother Succ-u-bus in the Bilge Room, letting you retrieve any items that were posted without an address. However, if you move quickly enough before the parrot escapes, you can instead post it before it drops the feather — and if you don't provide an address, then it gets sent to the Bilge Room...
- In Zork: Grand Inquisitor, there is a glass box ("In case of adventure, break glass") containing a spell scroll, a sword and a hammer. It can be easily opened, but the clamp holding the sword will not let go. The obvious solution is to open the box, take the hammer, close the box, break glass. Then the clamp lets go and you can take the sword.
- Darths & Droids In episode 1643, Jim — a player known for plans that he thinks are brilliant — has his character suggest a method of finding the planet Toprawa that ultimately hinges on raiding the Imperial data facility... which is on Toprawa.
- In Goblins, the Key of Darkness is inside the locked Well of Darkness because the adventurer who carried it in was killed by a trap.
- Zoë's first line in Sluggy Freelance is "Help! I need a phone! I locked my keys in the car with the engine running!" This is also referenced later when she temporarily moves to a place with normal people. (Oh, and Clem.)
- Subverted in Tower of God, episode 295: the Ten Bosses of the Name Hunt Station are trying to keep the protagonists from finding a certain key by having one of their number keep it hidden in a room that can only be opened with the same key. It turns out that that part doesn't really matter, though, since the room can't be locked from the inside.
- In The Whiteboard, Doc and Roger are faced with the need to open a safe without destroying the contents, ruling out their usual more "energetic" approaches. They do figure out a nondestructive solution, and once the safe's open, they find - the combination (along with a few other things).
- When The Angry Video Game Nerd needs to open the plastic packaging of a Tiger Electronics wristwatch game, the Bullshit Man randomly shows up to hand him a pair of scissors, then launches into one of his signature rants complaining about plastic packaging that needs scissors to open, noting that scissors themselves often come in such packaging.
- The first gift that the Lets Player raocow received during 2014's 'an advent Christmas thing' from his community on the Talkhaus was labelled 'Good luck!!!', and was sealed to the degree that raocow had to source a knife and a pair of scissors to open it. It contained another knife.
raocow: [between fits of laughter] Go to hell!
- Averted in Stuart Ashen's review of the Packbuster (a multitool for opening the packaging around products). The blister pack has a notch cut into one corner so you can open it without using scissors or the Packbuster. As Stuart puts it: "Extra bonus points for that; that is good. There's nothing like buying some sort of device for packages and not being able to get in the package."
- Rinkworks Computer Stupidities:
- A computer teacher plans to hold a class on routers and requests a half dozen from a colleague. The routers are shipped in a pair of cargo boxes secured by combination locks. The page with the combinations is inside one of the boxes.
- A user tries to sign up with an Internet Service Provider, only to discover that access to that ISP's website to set up the account requires a username and password from that ISP. In other words, you need to be a member to access the site to become a member.
- Ruby Quest: After smashing open a medicine cabinet and retrieving the tranquilizer inside, Ruby and Tom confront Stitches and tranq him. They notice he was carrying the key to the medicine cabinet. This is also an example of Off the Rails - Weaver (the GM) expected the players to kill Stitches to get the key, but a bit of Cutting the Knot meant they didn't need to.
- Parodied in the Family Guy episode "Petarded", where a flashback shows one incident where Peter locked his keys outside his car, trapping himself inside.
- In one version of the backstory for He-Man and the Masters of the Universe (1983), Prince Adam was questing with Teela for what would later become his magic sword. Wielding this sword was the only way to enter Castle Grayskull. And yes, the sword was inside the castle.
- House of Mouse: One of Mickey's opening monologues has him mentioning that the Seven Dwarfs left their keys in their minivan, and that it took a whole hour to get Dopey out. Footage of the incident shows Dopey mockingly waving the keys from inside.
- In a cartoon episode of Lucky Luke, the usual criminal Dalton Brothers were trying to be honest, and to have a honest work, they open their own bank. At one point Averell Dalton is commanded to open the safe, but he can't remember where the key is, so he opens the safe with dynamite. It turns out that the key is inside, and Averell closed it in there "for safety". Joe Dalton is not amused.
- In one episode of Phineas and Ferb, Dr. Doofenshmirtz finds the door to his truck won't close. He spends sometime struggling with the door, finally gets it shut and locked, and then looks in through the window:
Doofenshmirtz: "Those are my keys, aren't they?"
- In The Raccoons episode "The Intruders!", Cedric and Ralph accidentally get locked inside of Cyril's vault, which is programmed to not open up until Groundhog Day. Cyril points out that there is a key that Cedric can use that can override the system, which is locked in a safe within the vault. Or at least there would have been, if the pigs had actually bothered to put it there...
- Rugrats: In the B-plot of "Be My Valentine, Part 1", Chas rents a car to go with his costume for a Valentine's Day party the parents and their children are going to. However, he accidentally leaves his keys in the car, which is locked, so the adults try unsuccessfully to unlock the car door.
- Played in The Simpsons episode "Marge Vs The Monorail, where a scientist said to Marge the monorail "better to have a damn good conductor". Gilligan Cut to Homer trying to pry open the monorail's cockpit door because he locked his keys in there.
Homer (to Bart): Get a rock.
- In What's with Andy? episode "The Great American Lock-In", Andy reverses the locks in the front doors of his school, then lures in Lik and Leech. Unfortunately, he has dropped the keys outside of the school.
- An episode of The Wild Thornberrys has the family locked outside of the van whose new security system can only be opened with a remote control, and said remote control got locked inside the van.
- This trope is possible for anybody who keeps the passcode to unlock their mobile device in a writing app within the device itself.
- The doors of many apartments and hotel rooms behave like most padlocks: The key isn't necessary to lock them (simply closing them is enough), making it very easy to lock the keys inside. Dorm rooms as well, as many a college student who forgot their key when they go to take a shower can attest to.
- Many cars avert this by making the front doors require the key to be locked from the outside (by disabling the "lock while open" feature). One can still lock self out using the back doors, but you'd almost certainly have to be doing it on purpose. It's also worth noting that this and similar safeguards came about because locking your keys in the car was such a pervasive issue. It may be largely averted now, but that's a relatively recent development. However, it can still be possible to manually lock the door by pushing the lock post down, even if the electric lock will unlock the door. And sometimes it will only prevent locking if the key is in the ignition, but not if it's sitting in the seat.
- In his memoir Carrying The Fire, Apollo 11 astronaut Michael Collins devotes some time to explaining why good cockpit design is important. He describes an example of bad cockpit design: there used to be an Air Force trainer with a placard mounted on the canopy rail that listed all the steps of the ejection procedure. Unfortunately, the first item on the list was jettison the canopy.
- Many trains in Great Britain are provided with little hammers that have a notice saying that in the event of an emergency, the hammer should be used to break the windows of the train. The little hammer is always in a little box with a transparent cover and no way of opening the box or breaking into it. Many travelers have wondered how they are supposed to break the glass to get the hammer that allows them to break glass.note An even more extreme variation in some Mexican cities: the hammer needed to break the glass is actually outside the glass box... covered by a metal case that's screwed to the wall.
- If a bell.net user forgets what their password is or their account is hacked and the password is changed, they are still required to log in to reset it, despite the fact that without the correct password, logging in is now impossible.