Perfect Poison

"Evil Witch Sleeping Apples": One bite and you're out like a light!^note "Wake Up Kiss" sold separately.

Shackleforth: "Glove cleaner", huh? Say... you sell much of that stuff?
Daemon: Now and again.
Shackleforth: By the way, what's in it?
Daemon: No trace, no odor, no taste, no way to detect its presence. And it's sure. One thousand dollars...

— The Twilight Zone (1959), "The Chaser"

When murder by poison is depicted in fiction, it never takes more than a drop of liquid or a pinch of powder for the victim to grip their throat, cough a bit, and keel over. Quick, clean, and quiet. The reality is not so simple. To kill someone with poison, either quickly or without arousing suspicion, can be a surprisingly complex process.

Outside of highly controlled chemical munitions, there are very few substances available to the average murderer that can kill a human being as quickly and easily as the poisons of fiction. Some famous poisons (such as arsenic) require small, repeated doses to build up enough concentrations to kill without arousing the suspicion of the victim. In significant quantities, such poisons can taste extremely bitter, hence why many historical rulers had food tasters. The mechanisms by which these poisons kill can also cause dramatic physical reactions in the victim. While it is true that they were once very hard to detect, these old standby poisons are easily and routinely detected by modern forensic pathology.

The sort of poisons that can kill very rapidly at small doses tend to be staggeringly dangerous to the poisoner himself, not to mention exceptionally hard to come by and hazardous to manufacture.

There's also the matter of "getaway time" — a fast-killing poison is more dramatic, but a slow-killing one is harder to link to its source.

This is generally assumed to be the kind of poison used in a case of Finger-Licking Poison. Frequently has an Improbable Antidote. May or may not be purple or green. Naturally, part of its perfectness is usually that it works on everything. If ingested, expect to see the spilled drink to dissolve the table. Compare Instant Death Bullet and Instant Death Stab for other murder methods that work much faster in fiction than in real life, and Instant Sedation for non-lethal drugs displaying similarly unrealistic efficiency.

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Examples:

Anime & Manga

• Case Closed:
  • APTX-4869 is used by the Black Organization as an untraceable poison. For the majority of victims it works as intended, but for two of our protagonists, it's merely a Fountain of Youth. Poisoning people wasn't the drug's original purpose (what it was for we still don't know) nor does it seem to be inherently untraceable, but its effects on the body are so unusual and so different from that of any publicly known drugs that forensics can't recognize the cause of death.
  • They do have quite a few incidents where a person is killed by poison from a single dose administered a short time before the victim dies. You'd think the killers would want their target to drop dead somewhere other than the place they were poisoned to throw the police off the trail and give them time to dispose of the evidence, but that never occurs to them.
• Averted in JoJo's Bizarre Adventure: Phantom Blood, where both victims Dio poisons happen in steady doses over a long time.
• Partially averted in Naruto: the Sasori's Poisoned Weapons are said to take three days to kill their victim, though they still take an improbably small amount to do so. At least he has a reason not to be concerned about their being dangerous to him (since he doesn't have a real body, and is thus immune to the effects). If it were actually a bio-weapon of some sort, it would explain why it can kill even in small doses, never kills faster, and why it is so difficult to cure. Probably targeting the nervous system, given its paralyzing effects.
• Zigzagged in Ōoku: The Inner Chambers as while some poisonings were instantaneous, others weren't:
  • The cyanide poisoning of Iesada took years by slipping it in her drink. By the time Gosaku realizes she has been poisoned, it's too late to do anything about it. This causes Iesada to hastily denounce Western medicine, leading to the purge of the Ooku after her death.
  • It took a few years for Harusada to be fed enough poison to incapacitate her...and to make sure she didn't suspect anything, her taste tester O-shiga ate the poison too, covering up the symptoms with heavy makeup. The poison finally takes effect after Harusada tries to poison her own son Ienari. O-shiga lives long enough to explain to Ienari that it was a plot she and his wife Shigu cooked up in revenge for...
  • Harusada poisoning her own grandchildren, which happened almost as soon as they ate the poisoned sweets.
  • The poisons Yoshimune's older sisters were given also took effect pretty quickly, although it took them hours to die.
• Averted in Shina Dark. Poisoning Christina was done over many years.

Comic Books

• Batman: The Joker's trademark Joker Venom is sometimes depicted this way; special mention goes to its very first appearance,^note Batman #1, later modernized in Ed Brubaker's The Man Who Laughs where the victim stands perfectly healthy (if extremely nervous) for the first twenty-three hours, fifty-nine minutes, and fifty-nine seconds after exposure... and instantly keels over with the trademark death-grin one second later.
• Chick Tract: In Party Girl, a man who drinks a poisoned drink dies in less than four minutes.
• Teen Titans: Cheshire is a Master Poisoner that can make her poisons have all sorts of effects, such as paralyzing effects or being corrosive. She can make them appliable in and all sorts of weaponry, no matter the size, making even a scratch potentially fatal. She can also make her toxins to be odorless and nigh undetectable even by a master assassin like Lady Shiva or someone with enhanced senses with Catman.
• X-23: In X-23: Target X, an altercation with her high school biology teacher leads to Laura matter-of-factly telling him the best way to poison a person undetected (and since she used to be an assassin, she presumably is speaking from experience). Hilarity Ensues when she and her cousin are sent to the principal over this.

Fan Works

• In the Dangerverse, Narcissia Malfoy drinks a magical poison that gives her exactly twenty four hours to live, long enough to do quite a lot of confessing and taking her out of Draco's life, so he doesn't feel conflicted.
• In If Them's the Rules, Arcturus poisons his wife, Melania with a perfume. Played realistically as it takes a course of months for the poison to kill her, as much as a magical poison can be realistic.
• In MGLN Crisis, the poison Raquel Benna/Zettin drinks kills her within a few minutes, before help arrives.

Films — Animated

• Snow White and the Seven Dwarfs makes the poisoned apple from the original fairy tale explicitly magical - as part of a spell by the Evil Queen called the 'Sleeping Death'. It just gives the appearance of death and is immediate acting after just one bite. It can only be cured by "love's First Kiss" (in the fairy tale it just had to be dislodged from Snow's throat).

Films — Live-Action

• The pure heroin that ends up killing Ignacio in Bad Education (2004). Ignacio had become heavily addicted and was spending all of his money to obtain it, so his murderers made his death look like an overdose.
• The cardie-toxin TH-16 from The Body (2012). Álex puts a few drops into Mayka's wine glass. Diluted in blood, the toxin caused a cardiac 8 hours after ingestion without leaving a trace or linking Álex to his victim.
• Subverted in Crimson Peak. Lucille regularly poisoned Thomas's wives via their tea over a period of a few months. One eventually realised what was happening to her. Word of God is that Lucille killed the other two in other ways when she decided the poison wasn't doing it quick enough.
• "Luminous toxin" is the sure-fire poison in D.O.A..
• Elizabeth has a sequence where the queen is sent a dress as a gift, and one of her handmaidens wears it instead. She seems to wear the dress only for a couple of hours while having a tryst with Lord Robert - during which she starts to become aware of what's happening and starts screaming.
• Enchanted has a poisoned apple in keeping with its Fractured Fairy Tale theme. It's instantaneous and only cured by True Love's Kiss.
• James Bond:
  • In From Russia with Love, Blofeld pulls his first Blofeld Ploy, putting Kronsteen at ease by directing his anger at Rosa Klebb for their operation's failure - then having a mook kick Kronsteen with a poisoned blade. He drops dead in twelve seconds; Blofeld times it, observing that they need to develop a faster-working poison.
  • In You Only Live Twice a SPECTRE mook, trying to kill Bond, accidentally poisons Aki with a drop of liquid on her lips that kills her in seconds.
  • Averted in Skyfall, where it was the failure of a cyanide capsule, intended as a quick suicide, that drives the main villain's quest for revenge against MI6. This also averted the "quick and painless" part of the poisoning - even though it failed to kill him, the cyanide caused severe damage to his face and jawbones and left him in agony.
• In A Jolly Bad Fellow, Professor Bowles-Otterly develops a poison that is undetectable in a conventional autopsy and makes it appear that the victim has died of natural causes. It's only symptom is that induces intoxication and euphoria in its victims before it kills them. He uses it to eliminate those he considers useless to society.
• Subverted in Last Night in Soho. Ms Collins tricks Eloise into drinking tea that's been laced with something that makes her go drowsy after only a few minutes. But once Eloise realises what's happening to her, she's able struggle up the stairs. She makes a full recovery thanks to timely arrival by paramedics. It is admittedly never said if it's actually poison or just a sedative, as the plan is to pass it off as suicide, and thus just get her unconscious first.
• The Maids: A cup of tea mixed with an overdose of sleeping pills will cause the victim to peacefully go to sleep in some ten seconds. (In Real Life, it would probably make the person nauseated enough to vomit the pills back up).
• That Man from Rio begins with a thief stealing an ancient Mesoamerican statuette in a museum, killing a guard instantly with a poison-dart pistol. The police initially suspect cardiac arrest before the dart is discovered.
• Subverted in The Meg. Despite intentionally overshooting the amount of poison necessary to kill the Meg just to be sure, the shark continues to be extremely dangerous and would have killed Suyin and Jonas if the crew did not tie it up with cables and the poison finally began to work after several minutes.
• The fungus-based poison that Vann Siegert uses in The Minus Man is apparently tasteless and odorless, and kills his victims quickly and painlessly. The poison is discovered during an autopsy but without an autopsy, it could easily be mistaken for a drug overdose or heart attack.
• Mindhunters has a plot point where Nicole is killed by smoking a poisoned cigarette. Smoking it for only a couple of minutes activates the corrosive acid so much that it burns its way through the floor.
• Aversion of this trope is a major plot point in the second half of Alfred Hitchcock's Notorious. It's even stated outright that the poisoning must be done slowly so outsiders merely think the victim is ill.
• Just like in the original book, iocaine powder from The Princess Bride is odorless, tasteless, and causes nearly instant death from a dose small enough to avoid detection by the victim in a single glass of wine.
• Saw:
  • Invoked by Adam in the first film when he pretends to pass out from the poisoned cigarette after taking a couple of drags from it. It doesn't fool anyone.
  • The main game of Saw II involves a nerve gas released into a Closed Circle that will kill the victims unless they discover antidotes for each of them in time. While one victim (Laura) simply dies from the poison itself, it affects everyone at the same time, with the main sign of the effects being Blood from the Mouth.
• The Survivalist has three people stuck in an isolated hideout where supplies and forgaging can only feed two. Cue poison mushrooms hidden in the stew and a Poisoned Chalice Switcheroo.
• In Traffic (2000), the police informant played by Miguel Ferrer dies a few minutes after eating one bite of a poisoned breakfast. The only warning was his comment that the food "tastes like shit."
• The Wizard of Oz has a non fatal variety. Just a couple of minutes walking through the enchanted poppy field is enough to make Dorothy, Toto, and the Cowardly Lion go into a deep sleep. Of course it was enchanted by the Wicked Witch. In the book, Oz poppies just naturally have that effect, and moving them out of the field wakes them up immediately. In the film, snow of all things cures it.
• Thallium is presented in The Young Poisoner's Handbook as this. It is odourless and tasteless. Aside from the victims losing some hair, their bodies all react differently when poisoned with it, and symptoms could be those of a multitude of different ailments.

Literature

• In Before the Fact, written by Anthony Berkeley under the Nom De Plume Francis Iles, the existence of one of these is a plot point near the end of the novel. After a mystery writer lets it slip one does exist, the wife of a multiple-murderer realizes her husband will worm the information out of the writer and will escalate. She also realizes her husband will try to kill her and will succeed sooner or later, so she lets him.
• The Belgariad and Malloreon: Discussed. Even Nyissan Master Poisoners like Sadi have found there's no such thing as a symptomless poison, and most actually kill in somewhat over-the-top manners. To assassinate The Dragon without arousing suspicion, Sadi resorts to a poison that blocks the airway, so it looks like he choked on his food. The closest there is to a "perfect" poison, thalot (a guaranteed kill even against magic because it poisons everything in the victim's body), has obvious symptoms, takes several days to finish off the victim, and has one rare Panacea.
• Subverted in Best Served Cold by Joe Abercrombie. The opening scene with the master poisoner Castor Morveer starts with him telling his apprentice about the "King of Poisons", a toxin that is both completely undetectable and impossible to build up an immunity against, and should only be used against someone who is protected against all else to keep the secret. However much to the apprentice's dismay, the "King of Poisons" is merely a sham concocted by Morveer in case the apprentice betrays him.
• Books of the Raksura: There's an herbal poison that kills Fell within minutes, inflicts Instant Sedation on Raksura with no long-term effect, and is harmless to everyone else. It has no colour and a only faint, easily-disguised grassy taste, and is so effective that Fell quickly die just by eating the flesh of something that drank from a tainted stream.
• In Val Mcdermid's Clean Break certain people die from inhaling cyanide as soon as they open boxes of detergent. The narrator comments that the pathologist would not have known the real reason had the person who found the first body 'not smelt bitter almonds in the room and been a fan of detective fiction'.
• Codex Alera:
  • First Lord Gaius Sextus is fed small amounts of atropine for years by his second wife, a woman over 40 years his junior, allowing it to gradually build up in his system. When administered in small doses, the drug can be used medicinally. However, overdosing, even in small increments can lead to detrimental problems years later. The effects of the poison are so slow that the victim thinks that the discomfort and pain are merely signs that he's getting old.
  • A combination of poisons is used to take down a corrupt politician. The assassin uses heatfire and rancid garic oil. The first one causes the heart rate to increase to induce a heart attack with the benefits of blinding the victim. The second is deadly because the rancid nature and infections it brings. The source of infection is too great for the body to overcome before fever and delirium hits, and taking days to kill at that. To cure it, it requires a healer slowly chip away at the point of infection so the victim's body can destroy it. However, this means if the healing is stopped for any long period of time, the infection will be in more places, killing the person in an hour. So, combined, even a powerful healer will fall. Invidia Aquitaine survives the poisoned bolt, but only because the Vord Queen saved her in exchange for her allegiance, and she cannot survive without the aid of a Vord symbiote afterwards.
• Addressed and averted in Simon Spurrier's Contract: the main character and hitman Michael Point drills holes in his bullets, and notes (in monologue) that conventional wisdom suggests that he fill them with poison so that his targets will die even if they were only winged. However, he goes into great detail as to why most poisons are ineffective for this kind of use, too expensive, or just plain unattainable; eventually, he decides to fill each bullet with a thousand milligrams of pure heroin - dissolved with a drop of lemon juice - in the hope that even a nonlethal shot will result in a fatal overdose.
• This trope is discussed In-Universe in The Count of Monte Cristo, as the Count attributes the general incompetence of French poisoners to the overuse of this trope in the theater:
  Count of Monte Cristo: Now, shall I tell you the cause of all these stupidities? It is because, at your theaters, by what at least I could judge by reading the pieces they play, they see persons swallow the contents of a phial, or suck the button of a ring, and fall dead instantly. Five minutes afterwards the curtain falls, and the spectators depart. They are ignorant of the consequences of the murder; they see neither the police commissary with his badge of office, nor the corporal with his four men; and so the poor fools believe that the whole thing is as easy as lying.
• Averted in the Discworld novel Feet of Clay, which depicts an attempted arsenic poisoning fairly accurately. Even then it wasn't to kill him either. It was to keep him from doing his normal duties.
• Dune:
  • The poison used by the Great Houses for assassination and the Bene Jesserit's Test of the Gom Jabbar is Meta-Cyanide, a drop of which, administered by needle-poke, is enough to kill instantly. It's administered, respectively, in wasp-sized assassination drones, and by a Reverend Mother holding the needle to an aspirant's cartroid artery as said aspirant puts (usually a) her Hand in the Hole of a Pain-Inducer to test for Humanity. Baron Harkonen is killed when Alissa sticks him with a Gom Jabbar during the novel's climax.
  • The Water of Life plays with this trope. The extract from a juvenile sandworm is supposed to be so dangerous that just one drop would cause sudden, violent death. It is the mark of a truly gifted individual to be able to overcome the poison, which requires enough control of the body to be able to transmute the toxin within into a non-lethal psychotropic. A woman who can achieve this has the makings of a full-fledged Bene Gesserit. A man who can achieve the same...has the makings of The Chosen One.
• V.C. Andrews' novel Flowers in the Attic has a fairly realistic version of this trope: The unwanted children's meals include powdered sugar donuts that contain traces of arsenic. Each donut contains only a minute amount of arsenic so that the children will gradually and inconspicuously die after consumption of a significant number of donuts, and the powdered sugar ensures that they won't taste the poison's bitterness. The children unwittingly hasten the death of one of them by giving him all their powdered sugar donuts because he won't eat much else from the meals.
• Harry Potter:
  • Hepzibah Smith is killed when her house elf is tricked into thinking she's putting sugar in her cocoa when it's actually a "lethal and little known poison". As the elf is quite old, the authorities presume she just got confused and made a mistake. The actual murderer (Tom Riddle) had many other options available to kill her, but the poison was the most convenient way to Make It Look Like an Accident.
  • Ron is also nearly killed when he drinks poisoned mead that was sent to Slughorn as a gift for Dumbledore. He drinks a cup in one go and immediately collapses — only being saved when Harry gives him an antidote that was luckily nearby. Given that the target was an intelligent wizard who probably had several ways of curing himself on the spot, the poison had to be fast-acting. It wasn't detected while being delivered because the sender was Madam Rosmerta, a trusted friend, who was under the Imperius Curse.
  • Discussed when Snape suggests this as an alternative interrogation process to giving Harry truth potion (which he's out of) to suggest why it's a bad idea; most poisons act too quickly for much useful questioning to be done. Of course he could be lying to preserve his cover.
• Played with in The Hunger Games. Played straight with the Nightlock berries — they result in instant death to whoever consumes them. Subverted with the venoms President Snow used to poison his enemies — they did kill the enemies, but they also gave Snow sores in his mouth even when he took the antidotes.
• Averted in Madame Bovary by Gustave Flaubert. Emma Bovary attempts to kill herself by swallowing a large dose of arsenic. Instead of instantaneous death, Emma endures several days of intense and gruesome illness before she finally dies. Note that this is completely in-character for Emma, who has lived her entire life believing herself the heroine of cheesy romance story, while unfortunately only being the heroine of a painfully realistic and extremely cynical one.
• Mistress of the Art of Death: The death cap mushrooms that kill Rosamund in The Serpent's Tale are mixed in with so many different kinds of harmless mushrooms that it's impossible to tell where they came from. Also, one of the effects of the mushrooms' poison is that the victim appears to get better for a time, meaning it is both slow- and fast-acting poison.
• Subverted in Isaac Asimov's The Naked Sun. Someone tries to poison Hannis Gruer, but because murder is so rare in Solaria, they get the dosage wrong and Gruer vomits it up before it can kill him. It also creates an instant and very obvious symptom — Gruer's throat immediately burns after he takes the poison.
  Elijah Bailey: You poisoners on Solaria don't know dosages. Lack of experience. They gave him too much and he threw it up. Half the dose would have killed him.
• The Pale Horse by Agatha Christie has the murderer use Thalium as a poison. Notably, this has actually saved lives - Some people recognised the symptoms accurately described in the novel and were able to prevent either their own deaths, or those of others. Or, in a less pleasant outcome, were able to solve poisonings committed with Thalium because they'd read the novel and recognised what was going on.
• The short story "The Poison Necklace" by Miriam Allen deFord revolves around the eponymous necklace, the jewels of which are crystallized forms of various extremely toxic substances. The deaths it causes are nearly impossible to diagnose because the necklace looks entirely harmless, and the effects don't match any known poison. It was created solely as a science project, handled with gloves and kept under a bell jar, never meant to be worn.
• Peter Pan - Hook plans to poison Peter with a dose that he carries around always. It's described perhaps the most deadly poison in existence: so strong that it will kill the drinker almost instantly (as Hook carries it in case he's taken alive). However, its effects on Tinker Bell (who drinks it to stop Peter from doing so) can be reversed if children around the world affirm their beliefs in fairies.
• Prelude to Dune: Subverted in Dune: House Atreides, where Hasimir Fenring poisons Emperor Elrood Corrino IX at the request of the Emperor's son Shaddam with a chaumurky (poison that goes in a drink) that takes two years to work. The poison requires constant consumption of spice beer in order to work. Fortunately for the assassin, Elrood loves spice beer. Also, the effects of chaumurky become apparent within weeks, as the aging Emperor slowly begins to exhibit symptoms similar to senility. Given his advanced age, nobody suspects foul play.
• Iocaine powder from The Princess Bride is odorless, tasteless, and causes nearly instant death from a dose small enough to avoid detection by the victim in a single glass of wine. But one can develop an immunity to it.
• In the novel Raptor by Gary Jennings, there was a person who was a form of this. They looked like any ordinary person but had been systematically fed poison their entire life so that if you kissed or had sex with them, you'd die instantly.
• The Redwall series:
  • Farran the Poisoner employs such poisons in Salamandastron. Notably, the poison works a little too perfectly — to Farran's chagrin, the poison is so fast-acting that the first hare to eat the poisoned food keels over before anybody else has a chance to start eating, alerting the mountain's defenders that their food has been tampered with and leading to Farran's discovery and death.
  • The Wraith of Outcast of Redwall is another assassin employed against Salamandastron, this time by Swartt Sixclaw. He uses a tiny poisoned stone knife (called the Kisser), one scratch from which is swiftly and extremely lethal. Despite his weapon and natural talents with stealth and camouflage, Wraith's assassination attempt doesn't fare well — after an arduous climb up the side of the mountain, he goes to strike when his targets are having a comedic moment, takes a flung "otter rockcream" to the face, and accidentally stabs himself with his own dagger before falling back down the mountainside.
• The Saga of the Volsungs: Sinfjotli drops dead instantly after drinking a cup of poisoned ale.
• In A Song of Ice and Fire, which has fairly medieval technology, the "tears of Lys" are a poison that effectively duplicates the effects of a harsh fever, leading to an apparently natural death. However, it's stated that the death takes some weeks, and it may well require repeated dosages. More messily, another poison causes symptoms which resemble anaphylactic shock or choking/suffocation—but the poison is stated to have magic in it, and it may have been sourced from an order of shape-changing assassins, so it may be justified. Other than that, all poisons are detected by food tasters, kill over time, or are not used to kill at all; for example, one character doses another with a poison that leaves her indisposed for a day or two so that he can work uninterrupted. And in the case of the Tears of Lys, it also helped that the Maester in charge of healing the victim knew he was being poisoned and was ordered not to cure him. He subsequently covered up the death as "death by natural causes".
  • In another case someone is made to look like they choked on their own food by being poisoned with The Strangler, which constricts the throat muscles. However, during the autopsy, their throat is cut open and examined and found to contain no food.
• In the tale of Snow White, the wicked Queen tries to kill Snow White with poison twice: first with a poisoned comb, then with the famous poisoned apple. In both cases, the poison is undetectable and works as soon as the comb touches Snow White's hair and as she takes a single bite of the apple. Unfortunately, the downside is that as soon as the poison is physically removed from Snow White's body (when the comb is removed from her hair and when the piece of apple is jolted from her throat), she instantly comes back to life.
• Averted in Street Magic; the villain commits suicide by quick-acting poison to evade the authorities, and Briar finds the body and identifies the poison by scent, indicating that it was taken straight. In addition, he can tell from Lady Zenadia's body language that it was a painful death.
• Tom Clancy's The Teeth of the Tiger uses this form of instant undetectable poison.
• In Robert E. Howard's Conan the Barbarian story "The Tower of the Elephant" Taurus kills several lions by blowing a powder at them.
• In Dorothy L. Sayers' mystery Unnatural Death, Lord Peter Wimsey bugs his pathologist friend for information on these; meanwhile he's chasing a murderer who's been using something like one- air, injected into a vein.
• Attempted in The Broken Earth Trilogy when an unknown party tries to poison Alabaster with something described as being like botulism toxin. Unfortunately for them, he is able to talk Syenite through using magic to detoxify him before he suffocates.

Live-Action TV

• The 10th Kingdom:
  • Subverted where it was established that the Wicked Queen killed Snow White's mother by slowly poisoning her as her handmaid, then married Snow White's father and did the same to him. The same was done to Prince Wendall's parents by the new stepmother.
  • Played straight in the climax where the Wicked Queen has her chef create a poison so deadly, that tasting it kills him. (He didn't even swallow any of it, just touched it with his tongue).
• Babylon 5: While plotting to assassinate Emperor Cartagia Londo and Vir discuss the lengths they're taking to make sure the death looks like a heart attack. Injecting a minute amount of nerve toxin, directly between his hearts, with a needle coated with flesh sealant that would close the wound as it's withdrawn. Even then it takes long enough to kill him for him to get out a few last words, fortunately unheard by anyone but the two of them.
• Boardwalk Empire: Averted. The Commodore was poisoned with rat poison over a long period of time and in high quantities. While he is left violently ill and has to regrow his stomach lining, he still recovers to full health a few months later.
• Breaking Bad:
  • Walt cooks up a little ricin to deal with Tuco. It's odorless, tasteless, requires an extremely small dose, kills within a few days after at first appearing like the flu, and is so rare it isn't tested for. Later in the series, Jesse keeps around a "lucky cigarette" filled with the stuff, just in case. Ricin is used for actual poisoning only once, in the last episode of the series: Walt puts it into Lydia's tea, killing her.
  • Later on, Gus kills Don Eladio and all of his capos with a bottle of poisoned tequila. He drinks some himself and goes to the bathroom to force himself to vomit in order to avoid the worst effects. He requires medical attention, but the rest of the cartel die within a few seconds of each other and very cleanly.
• Castle: Came incredibly close, albeit thanks to some special (but not rare) circumstances. A popular talk-show host named Bobby Mann was found dead of a suspected heart attack. However, Castle, who was just on his show and had Mann whisper in his ear that he thought his life was in danger, suspects murder. Two tox screens came back clear, but at Castle's insistence, they dig further and find the truth: Bobby Mann was taking a very powerful medication for depression. The medicine reacts fatally with anything fermented. Knowing this, they realize the cranberry juice he was drinking was spiked with (fermented) balsamic vinegar, almost undetectable under the circumstances.
• Colonel March of Scotland Yard: In the "The Stolen Crime", a man who believes he has devised The Perfect Crime describes a new German insecticide that is colourless, odourless and tasteless, that vaporises when heated, and is fatal if inhaled. Later, his wife is poisoned using this exact poison.
• Copper: Played with. A police sergeant fails to recognize that the dead man has been poisoned because he decides to loot the man's belongings before examining the body. The sergeant even eats the cake that the dead man has not finished eating. The police detective who takes over the case quickly realizes that the dead man and the dead sergeant were poisoned by arsenic in the cake which they failed to taste because the cake was so sweet. If the sergeant bothered to turn the body over, he would have seen the vomit and the nasty state the victim's face was in.
• Criminal Minds:
  • Suggested in an episode where an old teammate of Prentiss winds up dead of an apparent blood clot after a run, despite being in great physical health. It's never confirmed what exactly killed him, with only the timing pointing at Arc Villain Ian Doyle, or even suggested that the authorities investigated further (Prentiss and the rest of her former team take it as a sign to GTFO before Doyle comes after them).
  • Typically averted in other poison-related episodes. "Untraceable" agents tend to be paralytics, used to enable other causes of death (such as one unsub who used it to frame his victims as suicides), and once the team knows to look for them, they're easy to find.
  • Another episode featured a former teammate of Stephen winding up in the hospital of an apparent heart attack despite being in great physical health (Hey! Wait a second...), and Stephen quickly finds an injection site that allows them to identify the poison (which, for bonus points, is radioactive, allowing them to track not only those who have been injected but also the home where the poison was kept, not only averting but annihilating the "untraceable" aspect). The poisoning did kill Stephen's friend, but neither quickly nor painlessly, and even the primary target, who'd received a much larger dose, stayed alive for quite a while afterward.
• Criminologist Himura and Mystery Writer Arisugawa has "Angel", a black-market drug that will cause instant, painless, untraceable death. Though intended to be used for euthanasia, the culprit of the episode sneaks it into a person's drink, and they die immediately upon taking a sip. It then turns out that the culprit was scammed, and their so-called miracle drug was actually just potassium cyanide — it still kills the victim immediately, but their death is painful and the poison is detected quickly due to the almond scent left behind.
• CSI: Subverted in an episode where the CSIs spend most of the episode looking for the instant poison that likely killed a high-stakes poker player. Grissom realizes at the end that it was a combination of factors — a "lucky" bullet stuck in his leg he never took out, plus a daily regimen of chocolates grown in a country where the cars use leaded fuel, plus a vengeful waitress putting eye drops in his drink — that combined to create a serious medical condition.
• Dallas: Subverted once, where a murdered victim was poisoned, and they died just when a trope Lights Off, Somebody Dies happened... Must have been Perfect Poison. However, when the murderer was confessing to their crime, they said the lights off had been actually a coincidence and that the victim had had a poison inside them long before that.
• Doctor Who: In the episode "Let's Kill Hitler", Melody Pond poisons the Doctor with a single kiss wearing lipstick containing the Poison of the Judas Tree. It's not instantly fatal, but it's perfect in the sense that it disables Time Lord Regeneration as well as killing the body. And it's non-toxic to Melody, averting the Universal Poison trope.
• Forensic Files: This series — which focuses on real-life law enforcement officers solving real-life crimes without Hollywood Science forensics — throws this trope up in the air in several episodes where a person has survived doses of poisons magnitudes larger than it would take to kill a person simply because they had been given small does over periods of years and had built up a tolerance to it. Cut to a graph of "Here's what would kill a normal person" and, six inches higher on the graph, "Here's where his/her levels were".
• Foyle's War: Subverted in an episode where the murderer offered his victim the Sadistic Choice of being shot limb-by-limb to bleed out or swallowing a cyanide pill. The murderer thought the pill would work instantly, but it proves to take some minutes longer to actually be fatal.
• Game of Thrones:
  • Tyene Sand - daughter of Oberyn Martell - coats her daggers with a poison called The Long Farewell. Although it takes time to work, death is guaranteed with a single drop unless an antidote is taken.
  • Arya Stark kills the men of House Frey (in retribution for their killing of her family and violating the sacred law of guest right) with poisoned wine, which makes them cough blood and drop dead within minutes of consumption.
• I, Claudius: Has a number of poisoners, all of whom dose their victims over a number of days to make it seem like they died of a wasting illness. One of the poisoners, Martina, advises a client against using the tasteless belladonna as a poison since it leaves a tell-tale rash, but the client doesn't listen and uses it anyway. (This later comes back to haunt said client, when she and her husband are brought in for murder charges.)
• Justified: Mags Bennett kills one of her henchmen with poisoned moonshine. The unidentified poison killed him in under two minutes, and he apparently didn't detect any smell or taste.
• Merlin (2008): Averted when Merlin reluctantly poisons Morgana in order to break a spell that's been placed over Camelot. After he tricks her into drinking from a flask of water containing hemlock, it takes a while for her to feel the effects, and is a very slow and painful process once she starts dying. She's also unconscious but alive long enough for him to threaten her half-sister to remove the spell in exchange for the cure.
• NCIS:
  • In the episode "Ephemera", a woman was poisoned by her brother over the family business. While the poison wasn't instant (the killer wanted it to look like she had died from a disease that had taken the lives of other family members, and thus passed off as natural causes), it was undetectable. Undetectable by 1970s science that is. An NCIS team using more modern equipment and techniques fifty years later was able to prove it was murder fairly easily once they had reason to look.
  • In "Obsession", a Navy lieutenant dies of an unknown illness. The NCIS team determines that he was poisoned using ricin, delivered into his body by injecting a tiny metal sphere thatcontained a lethal dose of the toxin. Truth in Television: ricin is among the most dangerous poisons known, and the method used to inject it is a real assassination technique used several times by the Soviet KGB.
• Sabrina the Teenage Witch:
  • Has an episode where poppies from the Other Realm turn out to be lethal to the Spellman family. Hilda and Zelda pass out instantly as soon as they see the flowers, whereas Sabrina is able to fight their effects for longer (as she's half-mortal). At the end of the episode, Sabrina has a "Eureka!" Moment and sends a snowstorm to the house, which removes the effects instantly.
  • A murder mystery episode reveals that unicorn essence is toxic to mortals, even when it just makes contact with the skin. As part of a spell to participate in a whodunnit game, Josh is the murder victim and this is how he dies. But of course it's undone with a Reset Button once the murderer is identified.
• Played with in Spartacus: Blood and Sand. In the prequel season Gods of the Arena, it's revealed that Titus's recent illness is a result of Lucretia secretly poisoning his wine over a lengthy period. His health worsens over the season, only dying after Lucretia gives him an especially large dose. There is however an extremely straight example where Melitta drinks the same wine once by accident and dies suddenly.
• The Twilight Zone (1959): Both the episode "The Chaser" and the story it's based on have expensive "glove cleaner", "totally undetectable to all forms of autopsy". The man who sells it also sells love potions... for five dollars. Because whoever drinks the love potion becomes obsessively and smotheringly in love with the person who gave it to them, to the point where the latter can't stand it anymore, he's expecting all of his customers to come back for the "glove cleaner"...
• Yellowjackets:
  • In "It Chooses", Lottie, calling it quick and painless, proposes to her fellow survivors that they pick a cup out of six cups in a tray. One of the six is laced with phenobarbital.
  • In "Storytelling" Walter offers hot cocoa mixed with phenobarbital to Kevyn. The former even calls it "surprisingly fast acting" when the latter just keels over dead without warning.

Radio

• Averted in The Adventures of Harry Nile. In on case, after the culprit feeds Harry rat poison, he has enough time to comment that he feels funny, sigh upon realizing he's been poisoned and then go to get his stomach pumped at the hospital.
• An old-time radio "Five Minute Mystery" titled The Radium Murder Case tells of a murder exposed because, according to the investigator, the poison used would instantly knock out the victim upon contact with the tongue. In this case, the poisoning was openly stated but the perpetrator attempted to claim the poisoning as a suicide.

Tabletop Games

• Realistic use of poison in most tabletop systems is extremely rare. This is mostly due to how roleplaying systems work — poisoning someone over weeks or months is usually hard to make work mechanically, and usually won't be on the list of how Player Characters off their opponents.
• Most poisons in The Dark Eye tend to be rather compromising than lethal to a healthy person (paralysing effects are popular), or spread their effect out over several hours or longer. There are a few quick killers though, with Purple Flash playing this trope completely straight. An ingestion poison with no distinct taste or smell, that can be dissolved in liquid, killing its victim within 30-60 seconds, with the only symptom being a purple clouded vision, and no way to trace it afterwards. A favourite among rich nobles.
• Dungeons & Dragons, in earlier versions such as 2^nd edition, poison would kill the victim instantly if they failed their saving throw.
• In Exalted; the most dangerous poison in the game (made from the concentrated hatred of demon gods and tremendously rare and expensive) would still take about seven seconds to kill most people (and would be rather obvious about it).
• In the RPG for Legend of the Five Rings, the Scorpion Clan (the underhand clan) sourcebook noted that while such poisons exist in-universe, their opponents have gotten good enough to detect such compounds, which would point back to them.

Theatre

• Shakespeare was in love with this trope. It seems like half his tragedies involve somebody getting poisoned with "the deadliest poison known to man".
  • Hamlet: is particularly striking.
    • Laertes returns from abroad to find that his father had been murdered. Fortunately, he just so happens to have purchased a phial of Super Poison that he's going to use for the old "dueling with poisoned swords" trick. Apparently that poison was available at souvenir stands all over France, next to the T-shirts and shot glasses.
      Laertes: "I bought an unction of a mountebank, so mortal that, but dip a knife in it, where it draws blood no cataplasm so rare, collected from all samples that have virtue under the moon, can save the thing from death that is but scratched withal." Act IV, Scene VII.
    • The ghost of King Hamlet also goes into lavish detail about his own death by poisoning — a poison that was dripped into his ear while he slept, and resulted in the most agonizing death throes, as well as hideous sores popping out all over his body.
    • However averted if you go by the theory that Ophelia was secretly pregnant with Hamlet's illegitimate child. One of the herbs she mentions is rue - and the dialogue suggests she plans to take that. It's a mild poison that was commonly used to abort babies, as it has the effect of making the body so sick it rejects the growing embryo. It can result in death if too much is taken, and we don't know for sure if Gertude's story of Ophelia's drowning is really how she died.
  • Surprisingly common Super Poison also appears in Romeo and Juliet: Romeo uses it to commit suicide after buying it from an apothecary who warns him that it has the strength to kill twenty men. Although as that poisoning was voluntary it probably wouldn't have mattered if it had had a distinctive smell or taste. He also drinks the whole bottle in one go. Juliet tries to take the same poison by kissing Romeo's lips, but there's so little of it left that it won't work quick enough.
  • King Lear has Goneril slipping Regan some poison secretly before the last scene. She is fine at first but then suddenly feels stomach pains and collapses immediately. Some productions will show Goneril giving it to her in another scene beforehand - implying it takes several hours to work.
• Appears in the classic Greek tragedy Medea. The eponymous Medea poisons a set of robes she gives as a gift to Jason's new bride. The poison instantly burns her to death, causing lots of Body Horror. It also kills her father when he tries to help her. Since Medea was a sorceress in mythology, it's safe to assume she enchanted the poison to be fast-acting.

Video Games

• 1001 Spikes explains the dart traps' quality of being able to kill instantly is because of them being poisoned. The Scorpions also qualify, because a single sting from them is immediately fatal.
• In Achaea, a large number of poisons are available and widely used in combat. Most only cause hit point damage or a status effect, but Voyria is invariably lethal...At least it should be, if it didn't take a full thirty seconds to do its work, during which the player receives six warning messages describing unmistakeable symptoms (mild fever, nose bleeding, bloody vomit, heavy breathing) and has only to take a sip of Magic Antidote to instantly save himself. As everyone carries antidote with them, the only practical way to kill someone with Voyria is to prevent the victim from drinking or injecting medicine.
• In Aviary Attorney someone dies frothing at the mouth moments after grasping a rose and exclaiming that they've been pricked by the thorns. The defense attorneys lampshade this trope, being unsure if any poison that strong exists. Turns out the real mechanism was a wolfsbane derivative mixed with caramel and made into the filling for fancy chocolates and took somewhat longer. Still undetectable, and strong enough that forty-five minutes after eating the wrapper which still bore traces of the chocolate another character is hospitalized.
• Dragon Age: Origins has a whole skill based around the creation of poisons and toxins to coat weapons with. These work instantly, though they generally have effects other than instant death (slows the target, does damage over time, paralyzes or stuns for a few seconds, etc.). Only Quiet Death can instantly kill, and even then it only has about a 5% success rate.
• Dragon Quest VII has the whole debacle in Verdham where Kaya is slowly poisoning her husband. The poison she uses is a powder which she keeps in a vial around her neck; her husband is convinced it's his medicine, and you have to get the bottle away from her and its contents tested to prove otherwise.
• The Elder Scrolls
  • The Elder Scrolls IV: Oblivion.
    • You can craft your very own poisons through alchemy for Poisoned Weapons. A common strategy is to mix multiple damage effects (e.g. Damage Health + Frost Damage) and/or have the poison also paralyze victims to keep them from getting aid.
    • There are also poisoned apples you can sneak into people's inventory. If they don't have any other food in there, they will eat the apples eventually and die. Mechanics-wise, they're scripted to specifically bypass poison resistance and cause a permanent damage health effect of 10 per second, so it's not quiiite instant. If you have a high enough health regen, you can survive, though it'll make the game much harder as you can't go to sleep again (can't sleep while being hurt). Cue the game ending instantly if you're forced to go to sleep, as your health regen drops to zero while sleeping as well.
  • In The Elder Scrolls V: Skyrim there is a powerful poison plant called Jarrin Root that is said to kill instantly. When eaten directly, it causes 200 points of poison damage, which is more than enough to kill any low-level enemies, but when combined with other poisonous reagents, and a high Alchemy skill, the damage can range in the thousands. Taken to the extreme, if the player has Alchemy 100, all available Alchemy perks, and the right combination of other ingredients, they can make a Damage Health poison with a damage rating in excess of 6000, which is more than enough to one-shot a Legendary Dragon! And if your chosen poison isn't powerful enough for a One-Hit Kill, or your "one critical shot" with your best bow happens to miss, one Alchemy perk allows you to use a poison twice, potentially allowing you to do enough damage with two hits to kill Alduin with as much ease as a basic Bandit. The only enemies capable of negating that are the ones with an inherent immunity to poison.

• The Final Fantasy series plays with this.
  • In gameplay, the 'Poison' status effect drains the character's HP slowly, but not fast enough that they can't have several turns. And even if the player doesn't have the cure (the 'Antidote' item or else 'Remedy' that removes most status effects), they can counter the effects by regularly topping up HP with healing items (or the 'Regen' status effect). Depending on the game, it might automatically be removed when a battle ends.
  • Final Fantasy VI has Kefka secretly poisoning the water at Dorma Castle to kill everyone. The water turns purple, and everyone who drank it immediately drops dead.
  • Final Fantasy IX has a different status effect 'Venom' - that is much worse than poison. It incapacitates the character completely, drains MP as well and results in a Game Over if the entire party is afflicted.
  • In Final Fantasy Tactics Dycedarg slowly poisoned his father over many years, which the rest of the family mistook for an illness.
  • Final Fantasy XV has 'Envenomed' that happens if the player steps in the pools of poison at the Daurell Caverns. It can't be cured but will wear off eventually.
• Averted in Ghost of Tsushima. A perfect poison seems to be what Jin has in mind when discovering concentrated wolfsbane poison. It turns out that instead a dart loaded with enough of the stuff to kill quickly makes the victim howl in pain and vomit blood. Still useful, if not what he was aiming for.
• Hitman generally plays it straight.
  • In Silent Assassin, one of the levels has as its target the son of a wealthy and powerful Japanese criminal. One way of achieving the kill is to sneak into the kitchen where a fugu dish is being prepared, and reintroduce the highly toxic liver to the dish. However, the toxin in the game works considerably faster than in real life.
  • Contracts has several levels where you're forced to look for poisons in the surrounding area and dose people's food or drink with it, and weedkiller or rat poison isn't exactly painless or quiet.
  • In Hitman: Blood Money, one of Agent 47's primary weapons is a syringe that can be used to inject targets at the jugular or to poison food, causing the victim to die the quickly and noiselessly. However, it isn't undetectable; kills with poison count as regular kills rather than accidents. The game also tries for some realism by using a mixture of chemicals rather than single one, specifically sodium pentothal, pancuronium bromide, and potassium chloride, the exact combination of chemicals used in lethal injection executions. The problem is, this is still Artistic License – Chemistry: in real life, they use multiple IVs so the poisons don't mix beforehand and undergo a process called precipitation (a fancy way of saying they get all waxy and won't go in), and it can still take two hours for the victim to die. It would work better to just use one of the first two (the more fast-acting drugs) and strangle the person after they pass out.
  • In the World of Assassination Trilogy they skip on explaining exactly what the lethal poison is (the vial is labelled FATALidomide if you squint) but it causes a victim who ingests it to retch and keel over within moments. 47 at one point states that it’s made out of “floral extracts”, including belladonna and wolfsbane.
• In an ending cut from Jade Empire, Sky dies from drinking poisoned wine.
• One of the ways Emma can bite it in Turtle Head Remastered is downing poisoned coffee. She's vomiting and knelled over within seconds of sipping it.

Visual Novels

• Ace Attorney:
  • In the third case of Trials and Tribulations, as well as the fourth case of Apollo Justice, the victim dies from cyanide poisoning and from a fictional poison, respectively, but in both cases, the killer was more interested in having the person dead than hiding the method from the police (as far as what killed him, at least). As a result, the victim did not have a swift silent death but instead gave full display of the poisons' physical reactions for all to witness, and the police have no trouble in figuring out what killed the victim.
  • In the first case of The Great Ace Attorney: Adventures, the victim was revealed to have been killed with curare, a poison which the Meiji era Japan had no scientific means to detect. Since curare paralyzes the muscles and halts breathing, the victim died in a restaurant filled with people, and nobody even noticed until the killer proceeded to make it look like he died from a gunshot wound. Furthermore, because of the specific way curare works (it has to enter the bloodstream directly through a wound to have an effect), the killer can take a swig from the poisoned water bottle in court without having to worry about poisoning themselves.
• In Cinders, Cinders can choose to kill her stepmother Carmosa with a poison that's stated to produce no noticeable ill effects in its victim until they suddenly drop dead of a seeming heart attack a couple of hours later. Its unusual effects could be handwaved as the result of it being crafted by a fairy or witch with access to magical powers, though. Plus, Cinders's poisoning attempt can fail spectacularly if Carmosa doesn't trust her and has the breakfast Cinders serves her tested for poison, which indicates that the poison's "perfect" qualities don't include untraceability.

Web Comics

• Sluggy Freelance: Pizza made of 100% cheese is absolutely delicious, but a single bite, improperly prepared, will yield a fatal coronary in seconds.

Web Original

• Protectors of the Plot Continuum: On their wiki, the PPC refers to this as "Ye Olde Poisonous Poison."

Real Life

• The assassination of Alexander Litvinenko, a prominent critic of then-president of Russia Vladimir Putin, was an attempt to use Perfect Poison which backfired spectacularly. Litvinenko was killed when someone sprinkled polonium-210 into his teacup. Polonium-210 has many advantages: it can be carried safely in a vial of water without detection, and while death is certain, the initial symptoms don't immediately suggest poison, giving time for the poisoner to make a clean getaway. Furthermore, unlike other radioactive substances, polonium-210 only emits alpha particles that cannot penetrate even a sheet of paper, thus making it invisible to normal radiation detectors (and requiring it to be physically ingested to work as a poison). However, they made one big mistake: they thought it was undetectable. While the technology to detect polonium-210 didn't exist in Russia, it did in the West. Oops. Furthermore, whoever did the actual poisoning seemingly didn't realize how much polonium-210 contaminates. Simply uncapping the vial is enough to leave detectable amounts. This made Litvinenko's murder one of the most unsubtle in history, with investigators simply following the trail of radioactivity back to the murderer's hotel room.
• Russian government operatives attempted to assassinate the anti-corruption activist and opposition leader Alexei Navalny with a novichok poison sprayed onto his underwear. Navalny was initially treated by physicians who suspected poisoning and preventatively administered an antidote before he was evacuated to a hospital in Berlin, which provided samples to five independent laboratories that could identify the poison before it degraded too far. After his recovery, Navalny called one of the FSB agents allegedly involved, posed as an aide to his boss, and got him to confess while berating him for his failure.
• Genghis Khan's father is believed to have been killed by drinking poisoned milk during a meal with rival Tatars.
• The preferred poison of Richard Kuklinski, AKA the Iceman was cyanide, stating that it was effective, wasn't messy, and hard to pick up in a toxicology test. His means of distributing it was either Tampering with Food and Drink, in an aerosol spray (stating the victim would look like they had suffered a heart attack), or merely spilling it on the victim.
• Karen Wetterhahn died after exposure to a tiny drop of dimethyl mercury on her gloved hand on August 14th, 1996. However, the death was long and drawn out, and she only began showing symptoms in December of 1996. Three weeks after showing symptoms, she slipped into a vegetative state alternating with periods of extreme agitation which was horrifying to watch with all the thrashing and stuff; however, doctors said she likely wasn't in pain - her brain was well beyond the point of transmitting the likes of pain signals. She did not actually die until June 8, 1997, when she was removed from life support. In this case, the poison wasn't untraceable. Weaponizing it would be tough: While a cheap supermarket squirt gun full of the stuff would ensure the deaths of targets better than a rocket launcher, we're talking something so toxic that if you know what it smells like, that means you've most likely taken in a lethal dose.
• The rumors spread about Lucrezia Borgia by her family's enemies often included a reference to a poison she made called "la cantarella." Even if the Borgias did have people poisoned, this particular substance was alleged to be such a perfect poison that it could not in fact have been real (according to some versions of the story, the poison could be fine-tuned to kill the victim a specific preset time after ingestion).
• The real-life poisons abrin and ricin are both very deadly, and can easily be manufactured from common ornamental plants, making the origin of the poison difficult to trace. In the assassination of Georgi Markov, identifying the organisation that was likely responsible (the Bulgarian Secret Police) was not done by tracing the ricin, but by investigating the capsule used to deliver the poison - a matching pellet had been recovered in the case of Vladimir Kostov, another Bulgarian defector who was attacked ten days before Markov's murder, although in his case, the pellet appeared to have been damaged before it entered his body and did not retain enough ricin inside it to cause his death. Neither poison kills as quickly as the trope demands, but they're about as close as real life gets.
• Subversion: Nerve gas, when aerosolized, kills in concentrations as low as a single droplet dispersed into an entire roomful of air, and in this form is both transparent and odorless. However, it causes a death so horrible, painful and noisy that it's plainly obvious what did it, and there isn't a great deal of detective work required to find out who did it - the range of suspects able to manufacture it (essentially, only governments who are not signatories to the Chemical Weapons Convention) is pretty limited. Fictional works that feature the use of nerve agents as poisons usually have the poisoner steal their supply from military stockpiles (e.g. The Rock, Michael Crichton's Binary.) This is increasingly unlikely in the real world, as the aforementioned CWC came into effect in 1997 and prohibits the "development, production, acquisition, retention, stockpiling, transfer and use of all chemical weapons" in 188 countries. (Of the countries that are not signatories, all but one - South Sudan, which did not exist as an independent country at the time the CWC came into effect - have been accused of possessing chemical weapons.)
  • A recent attempt to use a nerve agent as a poison in Salisbury, England, has demonstrated the above-noted flaws with chemical weapons as perfect poisons. The target, Sergei Skripal, and his daughter Yulia, both survived the attempt to kill them, as did police officers who came into contact with traces of the poison afterwards; one person, Dawn Sturgess, did die, but as a result of being accidentally exposed to the discarded poison container after the attempt; and all the evidence (the type of nerve agent used - one variety of Novichok, developed by the Russian government; the likely identity of the poisoners as captured by CCTV; and of course the likely motive for attacking a former Russian spy) have pointed squarely at Russia as the overwhelmingly likely culprit. Russia denies being involved, but President Putin recently referred on-camera to Sergei Skripal, calling him a "Scumbag" and "Traitor", which does not exactly help their case.
• The closest thing to a perfect poison is something that could be passed off as an accident:
  • Amanita mushrooms (death caps or destroying angels) could conceivably be eaten voluntarily by someone who doesn't know their mushroom lore, and do indeed cause yearly poisonings worldwide. The toxins in them are stable even in extreme temperatures, so the target will still die even if the mushrooms were cooked beforehand. The Deadly Webcap (Cortinarius rubellus) also deserves mention - a sugar cube-sized piece of mushroom flesh is tasteless, odorless and causes fatal kidney damage after one week. The toxin can easily be extracted from the mushroom by boiling, and is thermally stable.
  • Improperly prepared lima beans or tapioca can be deadly to eat.
  • Someone with a life-threatening allergy could be poisoned with the food they're allergic to, and that could be passed off as an accident.
  • Poisoning with botulinum toxin could be confused with someone having eaten improperly canned food. Fortunately, purified botulinum toxin is currently very tightly controlled. Medical and cosmetic preparations as Botox are only distributed in extremely diluted forms.
  • A form of poison which is hard to trace to a suspect is an excess of nicotine (injected in a dose much larger than usually lethal) in one of the victim's cigarettes. By the moment the victim drops dead, the said cigarette is already consumed, and autopsy reveals only that he or she had a lot of nicotine in the body. It's very unreliable for an assassin who does not have permanent access to the victim's personal belongings and therefore it has hardly been used. Also, a lethal dose of nicotine is usually a blatant giveaway of the foul play unless the toxicity screen test is provided several days after death.
  • In countries and social strata which have a problem with counterfeit alcohol, methanol is a near-perfect poison. It could conceivably end up accidentally in a counterfeit bottle of spirit (there are more than enough accidental methanol poisonings caused by non-malevolently contaminated rotgut). It's nearly indistinguishable from ethanol and produces the same effects as ethanol, followed by certain death if ingested in a typical recreational dose. This method of poisoning was used in the short story "Bargain" by A.B. Guthrie, Jr.
• Several animals produce toxins that could qualify as this. It should be noted that most of these critters are bright and colorful, which in nature means: Hands off. It should also be noted that these toxins wouldn't be a practical way for humans to poison each other. Very few people (mostly scientists) have access to these poisons and venoms^note the difference being that venom is injected while poison is absorbed through the skin, lungs, digestive system, etc., making them easy to trace.
  • Chironex fleckeri (a kind of box jellyfish commonly called the "sea wasp") produces one of Earth's deadliest toxins. As per this trope, the venom takes effect instantaneously: the sea wasp's sting causes excruciating pain and an intense burning sensation (like a red-hot iron). It's only deadly when the sting area is significantly big, but in fatal cases, the victim can die within two to five minutes if untreated. An average sea wasp carries enough venom to kill sixty adult humans. Even worse, unlike other similarly venomous animals, the sea wasp is nearly invisible underwater. And yes, Chironex fleckeri is found along the northern coast of Australia—but also along the coastlines of Vietnam, Indonesia, and the Philippines.
  • Other animals with quick-killing poisons and venoms include the blue-ringed octopodes of the Hapalochlaena genus, as well as many varieties of cone snails and poison dart frogs, all of which can kill within minutes if you touch them (except poison dart frogs, which can only kill you if the poison is ingested or enters the bloodstream through a cut or a poison dart). In fact, Conus geographicus is nicknamed the "cigarette snail" because its victims are said to only have enough time to smoke a cigarette before they die, though in reality, it usually takes several hours to kill someone. However, the toxins from poison dart frogs are far from perfect — they work by paralysing muscles, including those used for breathing. While this means they are quickly fatal if untreated, a victim can be kept alive by artificial or mouth-to-mouth respiration and will recover entirely in a few hours as the poison wears off. The same also applies to blue-ringed octopuses, but the main difficulty with them is that they're so small and don't have an immediately painful bite, so it's hard to tell someone has even been envenomated before it's too late to keep them alive.
  • Pufferfish (Tetraodontidae) deserve a mention here too. As per this trope, the symptoms appear almost immediately after the meat is eaten. First, the victim's lips and tongue go numb. Then come the dizziness and vomiting, followed by rapid heart rate, lowered blood pressure, numbness all over the body, and paralysis until death comes four to twenty-four hours later. Poisoning someone with pufferfish meat (or fugu in Japanese) wouldn't be particularly practical, though. The only people allowed to serve fugu are licensed chefs, and even if a fugu poisoning was passed off as an accident, it would almost certainly lead to public shame and a revocation of the chef's license. (Unfortunately, in Thailand, pufferfish meat is often served in lieu of other fish because it's cheaper and because fewer people there are aware of the danger.)
• According to conspiracy theories, the poison laboratory of the Soviet secret services created a poison gas called carbylamine-choline-chloride, or C-2. It was said to be odorless, tasteless, and could not be detected by autopsy, yet was potent enough to kill within fifteen minutes. Eyewitnesses claimed that the gas also caused victims to physically change, withering away and becoming quieter and calmer before death. No evidence has been provided to prove the existence of this poison.
• Succinylcholine—sux for short—is a drug used as a muscle relaxant in surgery. Because sux is processed by the body quickly and its byproducts are substances that naturally occur in the body, there have been cases where people have used it to commit murder by inducing respiratory arrest in the victim.
• There is no such thing as a universal test for poisoning, only a series of tests to detect if a certain category of pharmaceutical is in the victim's system. Thus, if a poisoner can find a toxin in a category the local coroner is unlikely to test for without good reason (running tests costs time and money), and administer it without giving anyone reason to check for said category of toxin, then they have found an effectively undetectable poison.

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