# How can you destroy a small device inside another person's head?

In a novel I am writing, everyone carries a small device in their head. The device is fragile, but the human head isn't.

How can this device be destroyed by another person quickly (i.e. within seconds) and in a realistic way, either with bare hands or some common implement (like a screwdriver or stone) that is easily available anywhere? No guns or other weapons (e.g. swords), as these are illegal.

The death of the victim would be a welcome side-effect.

This is a SciFi story, but the less futuristic tech is involved, the better. I would have liked to destroy the victim's head with a quick, powerful, Bruce-Lee-like punch, but from the research I have done this is not possible.

Since everyone carries such a device (think of the transmitter part of a distributed identity implant), it is built to survive what humans commonly do, including sports (boxing) and light accidents (fall from a bike). To get an idea of the fragility of the device, think of the brain itself. While a brain can easily be squashed with bare hands, you don't usually destroy someone's brain with a kick to the head. The device is like that: easily destroyed, if you hold it in your hand, but cushioned in the brain.

• "fragile": Think of a piece from a plastic bag.

Everyone carries that device. It is implanted at birth (or in utero, if you want). It cannot be heavy or hard, or it would damage the brain if the person fell and hit their head. It is light and flexible. It also must withstand all causes of death that do not destroy the head, because it is supposed to identify the dead person. So it doesn't disintegrate in a car crash. Also, merely killing the person doesn't destroy the device.

• "quickly": As my question states, I need to destroy the device within a few seconds.

Or security will interfere.

• "inside the head": That's where it is. It's not in the neck. It is always fixed to the same part of the brain, but brains are not all the same, so it is not always in the same place (unfortunately).

It's inside the head because that's where it is difficult to get out of, tamper with, or destroy, without killing the person. It's a security measure, not a technical necessity.

• The death of the victim would be a welcome side-effect. ?? IF that's the case, a hammer and chisel should do nicely. – nzaman Jan 17 '17 at 13:58
• I imagine destroying these devices/popping heads is as illegal as owning a weapon, so it's entirely possible your head popping criminals own weapons of some sort, firearm or otherwise. – SethWhite Jan 17 '17 at 15:27
• I think that "The death of the victim would be a welcome side-effect." is a major spoiler of an otherwise interesting question. With that, the answer would reduce to just "kill the victim, open the cranium using a knife, axe, hammer, gun, whatever, get the device and smash it.", which means that the question is asking just for "how to kill someone?" - The presence of the device becomes irrelevant. – Victor Stafusa Jan 17 '17 at 15:42
• You haven't really told us anything about the device other than, once removed from the brain, it's easily broken. We know nothing about what it can withstand in situ (telling us what doesn't break it, like boxing, doesn't help us understand what does break it). Should we assume that the only way to destroy this is to remove the brain from the skull and then remove it from the brain? That certainly would narrow the question! – Cort Ammon - Reinstate Monica Jan 17 '17 at 16:40
• When all you have is a sledgehammer, everything looks like a delicate chip embedded in someone's brain. – Xenocacia Jan 18 '17 at 8:42

Sharp object

If you know where the device is located (or it's fairly large) then a decent blow with a sharp object (such as a screwdriver or ice pick) will do the job. Heck, you could even use a stiletto heel if the device is by the temple or eye socket.

Brute force

If the device or its connections to the brain are fragile then even a strong concussive blow might do the trick: Nobody wants bits of unattached metal being rattled around in their cranium, so the device (or at least its connection to the brain) may well be destroyed by a decent bruce-lee punch to the head. Consider the increase in instances of brain damage amongst boxers since boxing gloves (which allow blows to the head due to lowered chance of fractured knuckles)

Magic Magnets

Strong magnets are readily available, and can be torn out spinning disk hard drives or bought. Depending upon the composition and location of the implant waving a suitably strong magnet past the head may cause it to malfunction or fail, though modern medical technology try to use non-ferrous materials (plastics, etc) wherever possible and delicate circuit boards are fairly simple to shield.

Bullets

The damage that a fragmenting or anti-personnel round will do to the human head is catastrophic, to say the least. I wouldn't rate the chances of an implant surviving if a headshot occurred. Of course, this requires access to a gun or similar munitions.

Strong electric current

If this situation happens somewhere inside, your character might be able to rip a power cable from somewhere and hold it against the head of the person. Electrocuting the device would probably lead to similar results as with the EMP device. This would avoid the mess of physical violence.

Bare hands

The device is probably very small, since there isn't much space in the skull. So there is actually only the brute force method left, hit that skull until you are able get to the device and destroy it. You would need a blunt weapon, a pipe or a baseball bat. This is something that is near to impossible, with your bare hands. Trying to penetrate the skull with a screwdriver to hit the device is useless, just think of the force required to drive the tool through the bone of the skull. Moreover you don't know where the device is located, and the brain is very soft, so even if you manage to hit the device it will probably just be pushed around in the brain.

Maybe you can rethink your story a bit, your character obviously knows of the existence of this dangerous device before getting into this situation, why wouldn't he have the time to prepare for this encounter?

EMP

Electronic devices are susceptible to an Electromagnetic Pulse. There are ways of building an EMP generator that even kids could pull of.

Devices caught in the EMP radius are rendered unusable or damaged beyond repair. People on the other hand are relatively save from it.

Just like people with pacemakers need to keep their distances from strong magnetic fields your character could destroy that device with such an EMP.

• This is a nice idea, but anyone wanting to use an EMP would have to prepare for the attack, buy the parts, and build the EMP generator. Therefore your answer does to meet my requirement of "bare hands or some common implement that is easily available anywhere". – user8976 Jan 17 '17 at 11:12
• Updated the answer, there are still very few things you can do in such a situation. – r41n Jan 17 '17 at 11:27
• EMP and passing an electric current through something are two very different things. And if you think that somebody being electrocuted by having cables held against their head "avoids the mess of physical violence" then, er, well, you're wrong. Very wrong. Lethal electrocution is very violent and most such deaths are rather messy. – David Richerby Jan 18 '17 at 16:31
• @DavidRicherby I said that it probably would lead to the same result (device rendered inoperable), not that an EMP and electrocution are the same thing. Also, you would need one hell of an electrocution to make his head explode, which is the mess I was talking about. – r41n Jan 19 '17 at 8:59

## Use a backdoor

Every living human having intracranial identity implant means that either the implant is EXTREMELY popular, or the setting is a dystopian hellhole where there is no free choice. Either way, in both these cases, there is no way the government won't have at least some interest in the implant.

In the case of "it's willingly", that means that the government will most likely want an easy way to control the implant in case of emergency: marking a criminal on the run so they set off alerts when they're passing certain detectors, allowing emergency passage past an identity checkpoint, making someone into someone else for witness protection programs,...

In the case of "dystopian hellhole", The government will most likely have backdoors installed that they can use to opress their subjects. An electroshock to the brain is enough to take most people down,... or it could be a bomb.

Such a backdoor would require external stimuli that can be deployed from a distance. You're not going to convince Jason Bourne to submit to surgery midway through his conspiracy busting. What would work is a special sensation, uniquely tuned to each device. You might have a special color pattern to trigger the "requires extra scrutiny" step, or an olfactory sensation that activates the "shock the brain" option.

• Exploiting whatever communication the device has is a good idea. However, I think there's a bit of a problem with your 'On the run' example. I don't think it's very likely that an implant will carry a users identity so much as it carries their ID (A cryptographically secure token.) The authorities would flag you as a fugitive on their servers, rather than telling the implant to flag itself is a fugitive. This prevents a hacker from setting is_fugitive to false – UIDAlexD Jan 17 '17 at 18:12
• @UIDAlexD Yeah, I realized the same issue while writing the answer. Still, it doesn't really matter. There are some things on the implant that you would prefer to store locally instead of on a server due to connectivity or time restraints. I can't think of an example offhand, but if anyone has any practical examples they can think off, I'll edit them in. – Nzall Jan 17 '17 at 21:09
• Here's an idea. Issue their implant a hard-shutdown command. Since they now have no IFF Transponder the next time they walk near an automated security checkpoint they'll be flagged as a hostile intruder (and possibly gunned down by sentries.) – UIDAlexD Jan 18 '17 at 1:01
• @UIDAlexD You can achieve the same result by marking them on the server as "dangerous! to be shot on sight". – Nzall Jan 18 '17 at 9:12
• @Nzall it could be used like medical bracelets are currently - Paramedics could "ping" it to get important medical details (allergies, pernament health problems etc). This could be quicker than looking up medical details from whatever heath service exists, won't be affected by communication outages or dead-zones and cheap readers could be a common item in first aid kits letting non medical professionals (first aiders etc) access the information in an emergency. – Baldrickk Jan 18 '17 at 9:22

### Nail gun

While not universal, a nail gun is a reasonably common tool and would work for this purpose. Essentially what you want to do is to drive a nail through the person's skull and the device. This might kill the person or just cause brain trauma.

My first thought was a captive bolt pistol, but you don't want the person to be carrying a weapon.

Another alternative would be a hammer and chisel. A bit clumsier and more likely to miss, but also serviceable. Substituting a screwdriver for the chisel and a stone for the hammer might work but is even clumsier.

Stabbing someone's head with an ice pick could work. Again though, it's much clumsier than the other alternatives. If the person moves during the attack, there's a high chance of missing the device. You might not even penetrate the skull.

A power drill could work, although you have to hold the skull steady while using it. And it takes longer than the other alternatives. By the same logic, a powered screwdriver with a sharp, strong screw. Some drill bits have a screw end to help get started.

For ease of use, the nail gun is by far the best choice among reasonably common tools. Everything else is more in the way of a making do with what's available choice.

I would rig a small microwave gun from the emitter off the MW oven in my house. Any signal the device might send gets overwhelmed by the microwaves and associated noise, the device is destroyed, and about the same time, its wearer dies. I'd stick the emitter inside a metal bowl, with a hole drilled through its bottom, to serve as a kind of parabolic antenna and to shield me from at least some of the MW radiation.

An electromagnetic pulse might be difficult to generate, however, a steady stream of the right radio frequency would be enough to cause the device to burn out (assuming it contains metal). A microwave oven could possibly be repurposed for this: http://www.pocket-lint.com/news/130161-man-turns-kitchen-microwave-into-lethal-weapon-survives

Not only would it be painful (and possibly cause death), but it's also sufficiently low-tech as to be possible with current technology and is also compatible with the size of the device: a small, flexible device wouldn't allow for much shielding. Any shielding that does exist would also have the disadvantage of heating in the person's head which would likely cause destruction of the device regardless.

In addition, 802.11 b/g/n wifi operates in the same frequency range. I'm not sure how much power would be needed to penetrate to the right depth in someone's head, but if a wifi signal could be amplified and directed with a parabolic dish, the same effect could be achieved.

Beyond that, not enough is known about the device. If exact dimensions of the metal contained inside is known, any kind of transmitter that outputs sufficient power and generates a radio frequency with a wavelength that causes that length of metal to resonate would work.

• Welcome to Worldbuilding. This is a great answer! – kingledion Jan 18 '17 at 6:24

Use knife for ice breaking.

In real live similar gadgets was used for transorbital lobotomy and it was the weapon of choice of Katrin Tremel!

So the owner of the head mustn't survive.

• Hammer (The bigger, the better)
• Axe
• (Cross-)Bow (can be bought legally here)
• Climbing Irons
• Tyres, fixed to a car, motorcycle, truck
• Needles (if you know where to aim at)
• Bricks

and last but not least:

• The Woodchipper (because Woodchipper beats everything)
• What's a woodcutter (if not the person)? – user8976 Jan 17 '17 at 20:24
• A chain saw?.... – Mad Physicist Jan 17 '17 at 22:31
• Or a wood-chipper? A wood chipper is in fact a great way to destroy body parts indiscriminately. – Mad Physicist Jan 17 '17 at 22:47
• Darn... Woodchipper.. Should concentrate on one job :/ Thanks for pointing out – Alexander von Wernherr Jan 18 '17 at 6:26

A sharp stick would do. A screwdriver, or a pencil... (do I hear Heath Ledger's Joker laughing in the distance?)

The skull itself might not be fragile, but it has holes in it.

Eyes. Ears. Nose. Base. Apply lengthy, hard object at will.

As others have noted, the more brutish methods of just smashing the skull with something solid are always an option. Mankind has developed many ways to do so over the millenia. A mid-sized rock will do if applied repeatedly.

We are such violent creatures... ;-)

• You only have a few seconds and you don't know the position of the device. Precision tools like screwdriver are probably not optimal. – Mad Physicist Jan 17 '17 at 22:47
• @MadPhysicist: The question is unclear in this regard. I just gave an angle other answers hadn't given yet. And a screwdriver through the eye is immediately fatal. You have a few seconds to wiggle it around, allowing for any variance in device position... – DevSolar Jan 18 '17 at 5:26

Knitting needle, upwards through the base of the skull at the foramen magnum. The knitting needle would be a better pick versus a knife or screwdriver since it could be bent as needed to reach wherever in the brain your device is located and still be stiff enough to punch through the soft tissue.

• You only have a few seconds and you don't know the position of the device. This is probably not optimal. – Mad Physicist Jan 17 '17 at 22:44

I don't think that your question is very good because since you don't care if the victim dies in the process, the easiest way to do it would be just to kill the victim quickly enough in order to severely damage the brain or perhaps completely destroy it. Even after your last edit.

Anyway, there are several easy ways to accomplish that:

• Blow a grenade in the victim's mouth.

• Shoot the victim's head with an anti-tank or anti-aircraft gun.

Ok, you told that you don't want to use something that you couldn't legally obtain to do that. So here are some other options:

• Drop the victim in a lava or liquid iron pool.

• Get a very big hammer and smash the victim's head against the floor, spraying a lot of brainy and bloody gore.

• Smash the head under the tires of a truck.

However if you want ways to remove the device without killing the victim nor severely damaging his/her brain quickly enough in order to not fire an alarm or something like that (that would be a good challenge), then we need to know more details about the device. Some ways to do it could be:

• EMP to deactivacte the device, which would be surgically removed later very carefully by a neurocirurgion.

• Hacking the device.

• Depending on the composition of the device, there could be some substance that could be injected in the bloodstream that chemically reacts with the device immediatelly and damages it unrecoverably without the victim dieing or suffering major bad side-effects in the process. If necessary, the remains of the device can be removed later by neurocirurgy.

• If the substance of the previous point could be absorved through the intestines and enter the bloodstream, it could be added to food or water to be ingested or being delivered as pills.

To address Mad Physicist's comment, we can fix the injection way with this:

• Make the injection not be unexpected. I.e. suppose that the patient regularly needs to take an injection of some drug due to some health problem (possibly a not real one that you just made up), then in some specific date, after regularly taking the injection normally as expected for some weeks, when nobody is seeing anything unusual, you either add the substance to the drug or just replace the drug with the substance. This also has the advantage that the substance don't need to act immediatelly, as long as it is able to shut down the device without it being able to detect that it is being chemically attacked.

• Also, if you are reallowed to kill the victim in the process, you could replace the drug to be injected with something nasty that will react both to the device and the victim's tissues.

• You only have a few seconds in which to operate, so injecting into the bloodstream would probably not work. Also, guns are not allowed, and grenades presumably aren't either. – Mad Physicist Jan 18 '17 at 2:56
• +1 for the first paragraph; the rest is just examples. :) – Wildcard Jan 18 '17 at 7:55

Since you don't mind if the bearer dies, an head shot with a shell of suitable size can do the trick.

If the size is correct the shell will have enough energy to pierce once through the bones but not twice, meaning it will bounce back and forth into the brain with easily imaginable effects.

• Ha ha, okay, in the US guns are certainly "easily available anywhere". If the urge hits you, you just go to Walmart and kill whoever you fancy. I forgot to exclude guns, because I live where guns cannot be that easily bought and no-one carries a gun in everyday life. I'll edit my question. Sorry for that. – user8976 Jan 17 '17 at 11:21
• We (the USA) really need to find a vehicle other than Hollywood and TV news for our global self-promotion. Yes, weaponry is easy to acquire compared to most of the world, but it isn't as chaotic and violent as our media make it seem! Remember: Chuck Norris just catches all the bullets for us! :-) – SRM - Reinstate Monica Jan 17 '17 at 14:11
• I didn't say "violent". I was in the US a couple of times and didn't get shot ;-) – user8976 Jan 17 '17 at 20:21
• @what. You are a true anomaly. Or perhaps you visited one of the knockoff countries that poses as the US? – Mad Physicist Jan 17 '17 at 22:33

We already have a need to destroy small structures inside the head without causing other damage. One thing that comes to mind is the gamma knife. Since the device here is made of material differing from human tissue, it should be even easier than targetingba tumor without bothering neighboring tissue.

Looking at other ways that brain surgery is performed without cutting it open, going through the blood vescles looks like a good approach.

So can these be approached without “illegal implements”? In both cases they are techniques used to treat real conditions which will still exist in yiur world. So we need to forge medical records or use serendipity to take care of the device “on the sly” while performing another needed procedure.

For home made tools, it seems possible to beam microwaves or high energy pulses from several directions simultaniously to converge on the target. I can imagine a back-room contraption that burns out the device that way, built from scratch using common electronic components.

• Yes but: The death of the victim would be a welcome side-effect. And: Where's the fun in that? – Alexander von Wernherr Jan 17 '17 at 14:17

### Just shove them

Really, I mean it. Of course, you have to make sure you pick a good location to shove them at. Good locations include the top of massive buildings, hot air balloons, the ISS, the edge of Mount Doom, etc.

If you are feeling adventurous, I would suggest arranging your accident here. It would seriously disrupt the entire battle if someone screaming suddenly fell right past those two. On the plus side, if your victim unlucky friend somehow survives the fall, underground beasts and horrors will finish the job.

Of course, if you're boring, you can always let your pet hyena, uh, mutant kitten accidentally munch on their skull for a bit.

Why don't you consider Lithotripsy?

It's a procedure designed for breaking up kidney stones without surgery, though I'm sure you'd be able to draw from this?

Any Google search will give you all the info, here's a link to a kidney lithrotripsy info page. https://www.kidney.org/atoz/content/lithotripsy

Goog luck with the book! (Fr Ted Crilley stylie!)

• The question states that it has to be a common implement and quick (measured in seconds). If I have to spend several minutes googling how to perform a Lithotripsy then I have already failed. – Anketam Jan 17 '17 at 21:48
• @Anketam. I would assume that you would not only do your Googling but also practice it well before the actual attack. The real issue is that you don't know where the device is in the skull... – Mad Physicist Jan 17 '17 at 22:45
• It's far from being quick. Since you need to fine focus a beam of ultrasonic waves, you need to do some calibration scans to do the tuning. Plus you need a set of ultrasound generators. "Hey, Jack, stand still while I calibrate this tool to smash that thing in your head" – L.Dutch - Reinstate Monica Jan 18 '17 at 5:35

Drill a (for example 1/2" or 12mm) hole with a cordless drill and insert a hose connected to powerful peristaltic pump. The visuals could be compelling.

It might not work in reality without some kind of mushing around because of the internal structures.

• You only have a few seconds and you don't know the position of the device. This is probably not optimal. – Mad Physicist Jan 17 '17 at 22:44
• Okay go the other way and, make a hole and pressurize the skull with a small gas cylinder (with one device). Like the movie Scanners. – Spehro Pefhany Jan 17 '17 at 23:33
• That's a very good idea. – Mad Physicist Jan 18 '17 at 2:48

Depending on the properties of your device, you have two basic types of options: direct energy transfer, and indirect.

Since you disallow the more sensible tools such as guns, any common piece of everyday equipment would do. For example, if your character is around chain saws or wood-chippers a lot, the path is pretty clear. Compactors like car crushers are also a good tool. The only possible downside is that they are relatively slow, so subject might have to be disabled first. Probably the most common device that could easily cause the required damage would be a car. A wheel could crush a skull and everything in it quite fast, especially after the subject is disabled by a couple of broken femurs.

Since you specifically state that the device is located in different places in different brains, using a precision tool like an ice-pick directly would not be a good idea because it would not be guaranteed to work within the few seconds that are allotted. However, a precision hole-making tool could be used to create an entry point, as @spehro-pefhany suggested in one of his comments. Then you could insert a canister of some kind of acid or corrosive gas that would fry the device.

If you prefer indirect energy transfer, you could use electric shock (which could be administered with common household items) or EMP (which would take a bit more setup). You could also use heat (flamethrower, oven, furnace, even pot of boiling water in a restaurant kitchen). Cold would probably be more difficult because even immersing the head in liquid nitrogen would not necessarily (A) cool the inside of the skull fast enough, and (B) disable the device. Many electronics continue to work just fine at super-cooled temperatures.

A pencil? Stabbing in the head with that adds quite some shock value, and isn't completely unrealistic.

As others say, any sharp (and some blunt) object will do. It's really a matter of the style in which you wish to express this. Tossing this nugget in once may add some guerilla-style variety to a potentially repetitive killing/ disablement of foes.

A small device holding kinetic energy. You can think of a portable, hand-sized railgun, except that it doesn't shoot enything.

You would hold it concealed in your hand ready to unleash the energy it store on someone skull.

|===] -> |===~~]

It could also be a device that can fit in the palm of the hand, and it would be sufficent to apply your hand on the victim skull and fire it.

• Are you thinking of a captive bolt pistol? – kingledion Jan 18 '17 at 15:04
• Yhea kind of, but more compact, unleashing more power. I have a blur memory of a melee kinetic gun in quake III or another game like it – user21263 Jan 18 '17 at 15:07

Small hole and pressure led me to a thought... a cannister of compressed gas (soda syphon CO2 or a cycle emergency inflater CO2 or a soda-stream gas bottle) connected to a needle and release valve. Whack it in through some convenient place (temple?) and hit the gas release, taking the inside of the head up to considerably over-pressure. If the device is fragile the pressure shock may break it. The temperature shock of expanding highly compressed gas may also be enough to break it.

If it isn't broken by that, the brain being driven out of any convenient apertures (ears? eyes?) and carrying the device with it would probably prove fatal to the device.

I think it's fair to say that the person carrying the device in their head wouldn't survive the experience.

You'd need to use CO2 or nitrogen or some other gas that had a high vapour pressure at ambient temperature... butane used like that would kill the person but wouldn't elevate the intra-cranial pressure that much.