Involuntary Suicide Mechanism

Gunther Hermann: It is a simple message I am demonstrating. We know where you are going and what you intend.
JC Denton: And I know something about you.
Gunther Hermann: You know you will be defeated.
JC Denton: I know your UNATCO killphrase: "Laputan Machine".
Gunther Hermann: I am not a machi—
[Gunther seizes up and spasms]
JC Denton: Sticks and stones...

— Deus Ex

An espionage/science fiction trope where agents/those who know important information are wired so that if they are interrogated, they will die instead of divulging any information. Generally, it's a sign of having a Bad Boss who doesn't care about the lives of his subordinates, although at least in theory, it could be a somewhat humane way of allowing the captured agent to escape some amount of torture.

Compare Cyanide Pill which is more "voluntary" and the related concept of the Explosive Leash. The equivalent for inanimate secret storage is Self-Destructing Security.

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Examples:

Anime & Manga

• Demon Slayer: Kimetsu no Yaiba: Muzan Kibutsuji doesn't allow the demons under him to say his name. The reason is that he puts a curse on them that will make his cells rip them apart very painfully from the inside out. A demon tricked into saying it learns this the hard way, and the results are graphic.
• In Hellsing, Jan Valentine falls victim to one of these: a chip implanted in his head sets him on fire (one of the few surefire ways to kill a vampire) when his mission fails and he is captured. He knew that it was going to happen and was happy when it did.
• The mooks in Until Death Do Us Part have explosives in their molars that they themselves can activate and that can be activated from afar. Soon enough, Mamoru just cuts their jaws out.

Comic Books

• Hunter's Hellcats: In Our Fighting Forces #122, the Hellcats are sent to undertake a mission on Crete. Before they leave, they are each fed a suicide pill that will kill them in 24 hours. If they succeed, they will be given the antidote at the extraction point. If they fail, the poison will kill them before the Nazis can torture them for information.
• In Judge Dredd, Mega City One Blitzers are hitmen with implanted explosives wired to detonate with the stress of capture.
• Suicide Squad: Members of the Suicide Squad each have explosives inside their bodies to detonate if they either (A) get captured, (B) fail their mission, or even (C) defy Amanda Waller.
• Watchmen: A low-tech version of this appears when Veidt pretends to be stopping a would-be assassin who he hired himself from taking a Cyanide Pill, but actually shoving the pill (which he himself had) down the other's throat.

Films — Live Action

• In Battlefield Earth, the sinister cabal of psychiatrists that rules the Psychlo race has implanted mind-control devices in their subjects' skulls, both to modify behavior and protect the all-important secret of teleportation. If an alien asks a Psychlo about teleportation or even mathematics, males are conditioned to go into a suicidal killing spree, while females go catatonic.
• Kingsman: The Secret Service: All of the rich and affluent people were given an implanted device that will protect them from the Hate Plague that the villain plans to wipe out most of Earth's population with. It also turns out that these devices can be remote detonated to blow up their heads if they try to divulge any information about the evil plan. In the climax, Eggsy sets off every single device at the same time, killing everyone greedy enough to go along with the villain's plan.

Literature

• Actors in The Acts of Caine are conditioned so that they cannot (on Overworld) admit they are Actors, speak Earth languages, etc. Approaching the topic can give them fits. They will die before they can say it. This only holds for the first book — it backfires when the natives of Overworld realize that the Aktir (as they call the Actors) cannot say the word, so between the first and second books the Actors have their conditioning removed.
• Oleg Divov's Brothers in Reason starts with an unknown cabal kidnapping random (or so we think at first) people in Britain and trying to use a mind-reading machine on them, only for them to have a fatal heart attack just when the machine starts receiving data. They try a different approach with the wife of an influential politician, who is caught in bed with one of the protagonists. Instead of using the machine, the cabal members show her the photos of her affair and then start asking questions. Just as they're getting to the interesting parts, she also croaks. It turns out they were all members of a sister secret organization that the other protagonist works for, all members of which have mentally implanted "kill switches" that are activated if unauthorized access is detected. It fails, however, when an extremely powerful psychic uses his abilities to disable the kill switch in one of the operatives, allowing the mind-reader to work.
• In Children of Dune, some people are implanted with a "heart-stopper" that will activate if they say the word "Jacurutu" (a place where people who are relevant to a certain plot live).
• Declare: Elana's handler uses one to try and kill her when she announces she's defecting to the French. Fortunately, she was praying when the hypnotic "kill command" was implanted, and this somehow disrupted it.
• From The Forever War:
  We were under no circumstances to allow ourselves to be taken alive, and the decision wasn't up to us. One special pulse from the battle computer, and that speck of plutonium in your powerplant would fizz with all of 0.01 percent efficiency and you'd be nothing but a rapidly expanding, very hot plasma.
• Wormtail's metal hand turns out to be this in Harry Potter and the Deathly Hallows, ultimately killing its owner as punishment for hesitating to kill Harry.
• Honor Harrington: The Mesan Alignment use these on their lower-ranking security officers, not only failing to tell them that they've put the implants in, but going so far as to have the implants kill in lots of different apparent ways so there aren't any statistical anomalies when Operation Houdini results in all of the non-expendable members of the Alignment having been extracted from Mesa and the Alignment gets to clearing up after themselves.
• The Laundry Files has this as a side effect of trying to defy a security geas. "The Concrete Jungle" features an interrogation running up against a tightly wounded geas that ends up cooking the subject's brain.
• In the Onyx Court book Midnight Never Come, Invidiana has put a spell on Tiresias that will kill him if he tells what he knows about her. He decides that it's worth the price.
• An occasional plot device in Perry Rhodan. Usually employed by villains, one pretty grim example actually repeatedly used by the protagonists during the Hetos occupation of the Milky Way Galaxy (though with no instance of it triggering ever shown) was an acid capsule implanted in the brain of members of La Résistance on missions where they might fall into enemy hands, designed to dissolve and release its contents under torture or upon death; justified by their enemies' technology potentially still allowing them to retrieve information from dead brains as long as those were still reasonably intact.
• In The Stainless Steel Rat's Revenge, when the local La Résistance questions one of the sinister "Gray Men" who have invaded their world under hypnosis, it turns out that the invaders have all been implanted with an "irresistible order" to die rather than reveal the name or location of their true home planet.
• In Starship Troopers, navigators who know the location of Sanctuary (the Navy's secret base/emergency backup homeworld) are hypnotically conditioned to commit suicide if captured.
• In The Stars My Destination, the crew of the Vorga were implanted with a mechanism that would stop their hearts if they started to give information explaining why they passed by the wreck of the Nomad and the protagonist, Gully Foyle. When Foyle starts torturing the first of the crew members, he dies the moment he starts divulging information. After the second time this happens, Foyle gets annoyed. Using the illegal Bullet Time reflexes he paid for, he knocks out his third target, cuts out his heart and connects his circulatory system to an artificial blood pump within twenty seconds. Then he starts questioning him.
• The Testament of Sister New Devil: The Master-Servant pact has an automated self-destruct option if the servant breaks a fundamental law. Like ratting out their conspirator master.
• Thursday Next: In The Eyre Affair, when an associate of Acheron Hades starts to tell the authorities what he knows, he spontaneously combusts.
• In the Tortall Universe, a death spell can be used for this purpose. It doesn't save the victim from torture/truth serum interrogation, but it kills him if he tries to give up accurate information. Aly comments to a captured spy that "if someone put three death spells on me, I'd wonder whether they trusted me at all".
• In the Vorkosigan Saga, Imperial Security agents are doctored so that they will have a fatal allergic reaction when given the universe's Truth Serum, which ironically was intended to prevent torture, but obviously, most people who know anything couldn't be given it. The protagonist was too politically important to be doctored in this way, but because of his odd medical history, he has an unusual reaction to fastpenta (becoming a Talkative Loon) and is able to exploit this to beat one interrogation he's subjected to in the series. His clone brother Mark, who has an undamaged metabolism, does have the standard allergy to fastpenta and would die if he received it. This usually doesn't become a suicide mechanism in the current era in-universe. It is standard policy for professionals to first test for a fastpenta-induced allergy before using the drug. In practice, this usually means the important operatives get to enjoy the old-fashioned interrogation methods.
• A fairly complicated version of this appears in the X-Wing Series. There's a drug called skirtopanol that is used in interrogating prisoners, since it lowers their defenses and makes them more sensitive to pain. But if someone's been taking lotiramine, the chemicals react, sometimes fatally. An Imperial gave lotiramine to someone he'd used, telling the man that it would protect him from a plague that was going around. When the local villain caught up with the Imperial, he told him that the man had gone into convulsions and died after being dosed with skirtopanol. The Imperial was surprised. He'd have had to have been taking four times the recommended dosage to go into convulsions.

Live-Action TV

• Agents of S.H.I.E.L.D.: The episode "Eye Spy" deals with a master thief being manipulated by an unknown party who has given her an artificial eye functioning both as a camera and an explosive to be detonated in the event of her being compromised or disobeying an order. Her handler turns out to be under the same control and is killed this way when S.H.I.E.L.D. catches up to him.
• Stargate SG-1:
  • The Priors are genetically programmed to burst into flame if they ever lose faith in their gods, the Ori. Though, Priors are so fanatically devout that this is hardly ever an issue, it's more common for them to trigger it intentionally.
  • The brainwashed za'tarc assassins are programmed to commit suicide if their mission fails or if someone tries to mess with their brainwashing.
• A possible example occurs in UFO (1970), though it could also be a fatal reaction to the truth serum due to the alien's different biology.

Tabletop Games

• Black Hats in the Deadlands: Hell on Earth RPG have microchips implanted in their skulls that explode if they commit treason against their leader in any way.
• Dungeons & Dragons:
  • Senshock, one of the demon lord Iuz's minions in the adventure T1-4 Temple of Elemental Evil, knows some of his master's secrets. If anyone (such as a group of player characters) uses Charm or any other Mind Control effect to make him reveal these secrets, Senshock will suddenly and mysteriously die, slain by luz himself.
  • Module DA1 Adventures in Blackmoor. All of the Iron Duke's agents in the Comeback Inn (as well as the Warden in the Prison Out of Time) have a special Geas placed on them. If anyone uses torture or magic to try to force them to tell about the plan to kidnap King Uther, the Geas will kill them.
  • Module OA5 Mad Monkey vs. the Dragon Claw. If the PCs capture any Dragon Claw monks while in the nation of T'u Lung and try to interrogate them in any way, the monks will burst into flames rather than reveal any of the secrets of their master. This effect is created by the demon Lung Jua (a.k.a. the Dragon Claw) himself.
• This is just one of the many occupational hazards of being a mook for the Eaters of the Lotus for Feng Shui; if you do or say anything contrary to what your Evil Sorcerer master wants you to do or say, the magical ward that he put on you will make Your Head A-Splode. A very nice example of this is what happens to any Poison Thorns your characters interrogate (which can only be done through magical compulsion because of their fear of this) in the adventure "Baptism of Fire", which features an evil Lotus sorcerer as the main villain.
• Explosive brain implants are a not-uncommon method for maintaining loyalty in Paranoia, notably employed (without disclosure) by the Shmegegi in Clones in Space.
• The Triads work these into their loyalty oaths in Shadowrun. Any Triad member who tries to reveal the organization's secrets after swearing these oaths will die on the spot, in a manner that depends on the Triad involved (massive internal bleeding and wounds spontaneously blowing open on the skin are just two of the known deaths). Note that this only covers betrayal to an outside organization; Klingon Promotion doesn't violate the oaths, as at least one Red Pole has learned to their advantage.

Video Games

• In Age of Empires II, you can activate one by researching Heresy, which causes your units to die if they're converted by enemy monks instead of actually going over to the other side.
• Baldur's Gate 2 has a magical version: The character Yoshimo has a Geas installed by his clandestine employer that stops his heart if he directly betrays, disobeys or fails said employer. If you do not bring Yoshimo with you to Spellhold, Irenicus will consider him not being there a 'failure' and invoke the Geas to kill Yoshimo offscreen.
• This is the fate of Vinceborg in Barkley, Shut Up and Jam: Gaiden.
• Deus Ex: All augmented UNATCO agents have one. Paul and JC can be remotely induced to suicide by giving their Nanomachines a command to grow uncontrollably, essentially giving them both super-cancer that kills them in hours. The previous-generation mechanical augments have implanted bombs with a Trigger Phrase, which JC can turn against them when he gets on UNATCO's bad side.
• Mentioned in the Mass Effect games in regard to Cerberus Mooks taken in for questioning... whereupon their heads explode. Mordin actually makes a joke about neural implants being more effective than explosives lodged in the teeth, as the latter can just be yanked out in case of defection.

Webcomics

• Schlock Mercenary: Para Ventura's handlers in UNS Internal Affairs implanted a remote bomb in one of her cervical vertebrae. She seems rather disturbed after Petey removes it and informs her of its presence — and of the fact that her handlers just tried to trigger it.

Western Animation

• Justice League Unlimited: Gorilla Grodd remotely shuts down Metallo after he is captured, but it isn't made clear whether this kills him or simply leaves him out of commission until someone can figure out how to fix him.
• Totally Spies!: One villain turns out to be an android who's only following the programming of the scientist who created him, who is also evil. He seems to be the scientist until the very end, at which point he has a Robotic Reveal and explains everything, including that he's programmed to self-destruct if he ever reveals that he isn't human... and so he does.

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