You are a double-agent in the most important war of the 20th century, The Falklands war. For years you have been playing the United Kingdom and Argentinian governments against each other, taking bribes from both sides and it has caught up with you.

One day travelling you are snatched off the street, kidnapped, drugged and placed on a private plane. You wake up in a cell, you know you have been taken by one of the governments to their capital for interrogation and treason charges but you cannot tell which has abducted you. You have perfected both the UK and Argentinian languages and accents and you know you can convince the guards to let you go if you were to speak in their native tongue asking for your government contact. However speaking the wrong language first will certainly turn out very poorly for you indeed.

You look around your cell, it is a large room with high ceilings, a musty smell, and thick dust covering everything. Based on being unable to hear anything and the constant temperature you conclude you are underground. Nothing about the architecture is distinctive. The only things in the cell are a single metal chair bolted to the floor in the center of the room with a spotlight hanging from a cord right above the chair illuminating the seat brightly leaving the rest of the room in shadow. You know it is a matter of time before you are tied into the chair and interrogated by shadowy agents of one of the governments.

You search desperately for a clue as to where you are. You kick the chair and stub your toe; it is solid. You claw at the light, looking for a marking or a way to open it and see the voltage rating but cannot find either. You yank and pull on it to test how secure it is and cannot dislodge it from the ceiling to get at the cord. You try to swing it far enough to smash against a wall but it will not reach. You search the chair for a makers mark but can find none. You know much more action will invite suspicion even if you know the right language so you stand back and think.

The guard watching on CCTV notices, but decides it is normal behaviour for someone waking up in a cell regardless of guilt so is not immediately suspicious. As far as he can tell you then pace around the room randomly for a few hours deep in thought.

You suddenly walk towards the door and knock, with 100% confidence you correctly ask in perfect Spanish for your government handler who promptly releases you.

How did you know what government to ask for?

  • You can assume you are correct in all your assumptions mentioned in the puzzle.
  • You have no items other than the clothes and shoes you were wearing when abducted. no cell phone, no watch, no pocket lint etc.
  • 3
    $\begingroup$ Nice story! Is this specific to UK and Argentina or can they be replaced with any two countries speaking two different languages? $\endgroup$
    – justhalf
    Commented Oct 24, 2014 at 4:37
  • 3
    $\begingroup$ The specific language or culture don't matter, but they cannot be replaced with completely arbitrary countries. $\endgroup$ Commented Oct 24, 2014 at 4:39
  • 11
    $\begingroup$ I love the depth and the clarity in what answers you're not looking for (light's voltage, markings, etc.) $\endgroup$
    – Xrylite
    Commented Oct 24, 2014 at 17:13
  • 3
    $\begingroup$ Having learned Spanish in high school from a teacher from Argentina and then attempting to use it in Mexico, I can assert you will not pass for a native. :-) $\endgroup$ Commented Oct 24, 2014 at 23:13
  • 4
    $\begingroup$ @TylerH Pretty sure it's a joke, mate :) $\endgroup$
    – Riking
    Commented Oct 28, 2014 at 8:42

12 Answers 12


I don't know how scientifically accurate this is, but it might be possible to use the light as a foucault pendulum to determine which hemisphere you are in. Of course, if there is a toilet (which is not mentioned), a flush would do the trick.

  • 17
    $\begingroup$ We have a winner. The last thing I did to the light was swing it to see if it hit the wall. Shuffling around was to mark the dust on the floor with the plane of the light. I welcome any ideas on improving the presentation, was my first attempt at writing a puzzle. $\endgroup$ Commented Oct 24, 2014 at 6:04
  • 92
    $\begingroup$ Great answer for the most part, but the toilet hypothetical would not work. Coriolis is negligible at such scale, the toilet's flush direction will be dictated by toilet design. $\endgroup$
    – The111
    Commented Oct 24, 2014 at 8:33
  • 44
    $\begingroup$ The Foucault effect causes the plane the light swings in to rotate by a quarter of a degree per minute. Sorry but there's no way that the light would swing for long enough at sufficient amplitude to detect that. $\endgroup$ Commented Oct 24, 2014 at 11:06
  • 48
    $\begingroup$ @martin No, no, one hundred times no. The idea that Coriolis forces produce any significant spin on something as tiny as a sink of water is a total myth. The water turns because it has some angular momentum because it wasn't introduced into the sink perfectly centrally. Test it yourself by pouring water into the sink from one side using a jug, letting it settle and then pulling the plug; then do the same from the other side and you'll see it spin the other way. $\endgroup$ Commented Oct 24, 2014 at 11:14
  • 25
    $\begingroup$ Implausible. The ceiling would need to be very high and the light fitting would need to be very heavy. Smithsonian suggests height 52 feet (16m), weight 240 pounds (109kg). With such specialist equipment you're not really in a 'prison cell' with a 'light fitting' any more, you're in a stairwell or an atrium with a metal bob that happens to have a light on it. Sorry. ;) $\endgroup$
    – A E
    Commented Oct 27, 2014 at 14:02

You think for a while and remember that Argentina had adopted the metric system way back in the late 19th century, while the metrication process in Britain had started just a handful of years before the Falklands War.

The only things in the cell are a single metal chair bolted to the floor in the center of the room with a spotlight hanging from a cord

You walk over to the chair and kneel down to get a closer look at the bolts fastening it to the ground. The bolts have the distinctive heads of metric screws.

But since the metrication process in Britain has been going on for a few years, you can't be certain that a metric screw indicates that you are in Argentina.

You look around your cell, it is a large room with high ceilings, a musty smell, and thick dust covering everything.

From the significant dust buildup in the room, you know that this room has to be pretty old. You gauge that if you were in Britain, it is highly unlikely that the room was constructed with metric screws.

  • 32
    $\begingroup$ I would say that this answer is so far the only answer that will survive a reality check. $\endgroup$
    – Ole Tange
    Commented Oct 27, 2014 at 8:24
  • 2
    $\begingroup$ Cement bolts would have hex heads in both systems, but still an excellent idea. You might be able to differentiate metric and SAE hex bolts if very familier. Seeing the threads would make it obvious but alas the bolts could not be removed. $\endgroup$ Commented Oct 27, 2014 at 17:22
  • $\begingroup$ There should be a number of places you could look to find bolts and fasteners. A large lamp would almost certainly need screws, as would the hinges on the door, and perhaps the table if it used screws instead of nails. $\endgroup$ Commented Oct 30, 2014 at 7:17
  • 1
    $\begingroup$ @JohnMeacham: It would probably be Imperial, not SAE, but the strength/grade markings on the heads should be different. $\endgroup$
    – jscs
    Commented Feb 25, 2015 at 8:41

Wave your hand through the thick layer of dust until you start sneezing. Eventually someone will say "Bless you" or the equivalent in whichever language, and you're good to go.

  • 10
    $\begingroup$ I'd probably go with pretending to be ill, but +1, just for practical thinking. $\endgroup$
    – Carl Smith
    Commented Oct 24, 2014 at 14:44
  • 7
    $\begingroup$ I saw the "thick dust" and thought "Aha! a clue!" $\endgroup$ Commented Oct 24, 2014 at 15:08
  • 1
    $\begingroup$ You were right it was a clue. Didn't think of playing sick, good idea. $\endgroup$ Commented Oct 24, 2014 at 18:59

Of course you know it's not the UK government because you have been left alone in your cell long enough to miss tea time, and it would be completely barbaric to not observe that sacred ritual. So, Argentina government it is!

  • 3
    $\begingroup$ No watch or sense of time, it could be 2am locally for all he knows. but that's a way i didn't think of. :) $\endgroup$ Commented Oct 24, 2014 at 4:31
  • $\begingroup$ Ah, luckily. I thought of the same solution, but it was too 'short' in comparison to the question :P $\endgroup$
    – Mathias711
    Commented Oct 24, 2014 at 4:47
  • 34
    $\begingroup$ It's 2:22am, I'm British and I'm drinking a brew, I see no flaw with this answer, $\endgroup$
    – Jon Story
    Commented Oct 25, 2014 at 1:22

Having learned from an ancient master the art of chronobarbology, you stroke your beard stubble and determine that precisely eight hours have passed since your abduction in Bogota, Colombia.

Factoring in the time needed to transport you to and from the airport, and the maximum realistic speed of a 1980's private jet, you realize you cannot possibly be in London and must therefore be in Buenos Aires, land of the Martín Fierro.

Or... you could just pass gas when the first interrogator steps into the room and observe whether his response is "Blimey!" or "¡Uy!".

  • 24
    $\begingroup$ Awkward moment when Googling chronobarbology gives only one result in the whole world wide web pointing to this answer. google.com.pk/search?q=chronobarbology $\endgroup$
    – M-Wajeeh
    Commented Feb 25, 2015 at 13:06
  • 1
    $\begingroup$ @M-WaJeEh made me laugh so much, good job. $\endgroup$
    – Aric
    Commented Aug 23, 2016 at 9:57
  • $\begingroup$ What is chronobarbology? its driving me nuts! $\endgroup$ Commented Dec 7, 2016 at 4:10
  • 2
    $\begingroup$ @Gokigooooks chrono = time, barb = beard, so it's the study of beard growth timing. $\endgroup$
    – Andrew
    Commented Jul 9, 2018 at 23:53

On walking around the room thinking for hours, he started feeling weird, like increased heartbeat, heavy breathing, feeling like less oxygen around the area, than normal. So he understood that he is currently in a high altitude area, preferably above 20000ft above sea line to feel such weird effects.

He knew the highest altitude in UK is some what about 4400ft above sea line and so Eliminated the possibility that he is in UK. Then the chances are he is either in Argentina or in some high altitude place outside UK or Argentina.

But he knew Argentina has places with altitude above 22000ft. Also he was sure that it's either UK or Argentina government took him. So he understood he is in some high altitude location in Argentina.

After all these deductions, with full confidence, he knocked the door and talked with the guards in Spanish.

  • 19
    $\begingroup$ Another excellent response I didn't think of, unfortunately not the answer as Buenos Ares and London are about the same altitude and I specified you were brought to the capital. However I feel this should be the answer to another puzzle we should come up with as i like it... could also be something like his shampoo bottles expanded or contracted. $\endgroup$ Commented Oct 24, 2014 at 5:25
  • 1
    $\begingroup$ Although it raises the question of 'how does he know he's been taken the the capital?' - or even the nation in question? $\endgroup$
    – Jon Story
    Commented Oct 25, 2014 at 1:27
  • 1
    $\begingroup$ That's why I stipulated that all of your assumptions stated in the puzzle are true. After all, you are a spy for both agencies, presumably you picked up some info on how they operate. $\endgroup$ Commented Oct 25, 2014 at 2:39
  • 1
    $\begingroup$ @JohnMeacham yeah, more a loophole in the original question than in the answer $\endgroup$
    – Jon Story
    Commented Oct 26, 2014 at 19:02

Unscrew the light bulb from the lamp, if it's bayonet style, you're guaranteed to be in the UK and not Argentina (with light bulbs inside of cars being the only exception), if it's screw-style/Edison style, then you're most likely in Argentina (although, that's not a 100% guarantee because some Edison style light bulbs can be found in the UK despite the fact that bayonet style light bulbs predominate in the UK).

You don't even need to turn off the light to find this out. A small twist should give you enough information without cutting off the electricity to the bulb. Just make sure not to burn yourself while doing this, use some of your clothes to insulate your hand.

  • $\begingroup$ Are you guessing here, or do you know for a fact that lightbulbs and bolts screw in counter-clockwise in Argentina? $\endgroup$
    – IQAndreas
    Commented Oct 27, 2014 at 13:28
  • $\begingroup$ After doing a little more research, I've amended my post. My post was originally wrong. $\endgroup$ Commented Oct 28, 2014 at 0:10
  • 3
    $\begingroup$ Nice comeback! (or whatever you would call editing in a brilliant solution to replace a flawed one) $\endgroup$
    – IQAndreas
    Commented Oct 28, 2014 at 19:42

Another lighting related one. Peel back a bit of the outer insulation on the light flex. If the wires inside are coloured black and red, you're in Britain, which had its own set of standards and didn't switch to IEC60446 (blue/brown) until the early 21st century, long after the Falklands conflict.

Be careful, mind you, or it's all going to be a bit academic.

  • 5
    $\begingroup$ Yeah, that would have been my first attempt too were I in this scenerio, which is why I went into detail about the attempts to find out the voltage or get at the cord not working. $\endgroup$ Commented Oct 27, 2014 at 17:31

Because you are so far underground, you have the unique position to feel any earth tremors in the area. Having visited the Andes multiple times, the chance of feeling an earthquake are good, but I believe that going further underground allows one to sense any earth tremors that would be imperceptible on the Earth's surface.

So, as you went "asleep" for a couple hours, you were actually concentrating to feel any such movements.

When you did, you were instantly sure that you were in Argentina and not in Britain.

  • $\begingroup$ I misread pace for sleep, but I still believe that one can still feel a slight tremor while walking. $\endgroup$ Commented Oct 27, 2014 at 23:07
  • 1
    $\begingroup$ I don't think so. San Francisco (the place where I live) has had: (M1.5 or greater): 2 earthquakes today, 6 earthquakes in the past 7 days, 49 earthquakes in the past month, and 516 earthquakes in the past year (and only a small fraction of those earthquakes can be felt by human beings, even underground). On the other hand Buenos Aires has had: (M1.5 or greater) 0 earthquakes today, 0 earthquakes in the past 7 days, 5 earthquakes in the past month, and 33 earthquakes in the past year. Source: earthquaketrack.com $\endgroup$ Commented Oct 27, 2014 at 23:29
  • 1
    $\begingroup$ The question states you're underground. Not how far underground. Therefore this answer is not applicable. $\endgroup$
    – Mast
    Commented Oct 28, 2014 at 14:56

When you knock on the door, listen to the guard's response and use his language.


Maybe you could use Spanish and English cognates (words that are pronounced nearly the same in both languages).

For example. what if you started a conversation with the guard by saying "legal error!" as if to say you got the wrong person. The only hard part would be a neutral accent.

Another example would be asking the question did I do something wrong? by saying "criminal??" while pointing at your self. And again the accent would be hard but maybe the guard wouldn't catch it.

there are a lot of cognates so you probable could come up with something.


So many great answers. But what about the CCTV? If it is in the room, you may be able to look at the manufacturer or the model. If not and you can still see it, you may be able to find something based on it's looks.

  • 6
    $\begingroup$ What if it was made in China? $\endgroup$
    – iminiki
    Commented Mar 13, 2019 at 6:40

Not the answer you're looking for? Browse other questions tagged or ask your own question.