The common term "truth serum" refers to any number of sedative/hypnotic drugs which are used to induce honesty in a subject. In fact, truthfulness is not guaranteed by the use of such drugs; while a person under the influence of a truth serum may become talkative, or may experience reduced inhibitions or even hallucinogenic fantasies, they are still quite capable of lying.note For this reason, and the obvious human and civil rights issues (which are similar to those regarding torture), any statements obtained in this manner are inadmissible in court. Or, they're really disgusting concoctions used in crossing the line ceremonies. The best that modern pharmacology can come up with is amobarbital (better known as sodium amytal) and is not all that useful at all.
Ah, but don't tell Hollywood that...
In fiction, truth serums of all forms (be they actual drugs, spells or whatever) behave quite predictably, and will invariably have one or more of the following effects on the subject:
- A person becomes incapable of lying, though still fully conscious and otherwise able.
- In many cases, the subject seems compelled to not only tell the truth but to talk, period. Simply shutting up and not speaking, which isn't a lie, never occurs to them — or, if they do try to shut up, they are physically unable to do so.
- As well, they have a tendency to go into far more detail than is necessary, when short, curt responses that aren't lies could still keep the secret. Compare I'll Never Tell You What I'm Telling You!
- Occasionally, they will be unable to lie, but quite able to be creative in spinning statements that are Metaphorically True.
- A victim almost always gives complete and accurate information, even though in Real Life, people who think they're telling the truth are often wrong.
If the trope-generator is positioned more towards the "Science Fiction" end of the scale, invariably the injected will start babbling about the Killer Rabbit / Ninja Pirate Zombie Robot / Little Green Men and be instantly dismissed as crazy or, at best, programmed to spout gibberish under interrogation.
While the body of this entry deals mainly with traditional truth serums, in fiction there are actually many methods of getting the truth out of someone besides drugs. These, due to being Applied Phlebotinum, can be excused for behaving as described herein. Sometimes. Maybe.
For the more historically tried and true method of extracting information by getting the victim completely sloshed on cheap booze, see In Vino Veritas.
Sub-trope of Enslaved Tongue. May overlap with I'll Never Tell You What I'm Telling You!. See also Lie Detector and Bad Liar for cases where the subject can lie but can't fool anyone.
- In Peorth's introductory arc in Ah! My Goddess, Urd gives her sisters a drug that will make them confess to any misdeeds they have ever committed in order to find out about an incident that made Peorth hate Belldandy. When Skuld takes it, she confesses to a variety of minor misdeeds. When Belldandy takes it, nothing happens.
- In Heat Guy J, Clair gives one to Daisuke, after receiving a Shut Up, Hannibal! from him that involved bringing up Clair's father. Clair was hoping that Daisuke would have a Heroic BSoD and spill some shameful or angsty secret. While Daisuke does have a dark past (his father was killed by Clair's father, and his mother walked out on the family), he doesn't let it bother him, so the drug did not work on him, apart from knocking him out.
- In JoJo's Bizarre Adventure: Battle Tendency, Speedwagon wakes up as a prisoner of the Nazis, who want to learn more about the archaeological find that the Speedwagon Foundation uncovered. The commander, von Stroheim, mentions a few details about Speedwagon's life story, not only providing a little exposition about Speedwagon's life after JoJo's Bizarre Adventure: Phantom Blood, but causing him to realize that the Nazis had injected him with truth serum and forced him to reveal information he does not want them to know.
- In Negima! Magister Negi Magi, in one of the later chapters, as Negi was running away from his cute students who want to know the name of the girl he likes using every means necessary, he got an injection of "truth serum" up his... "back side". It still didn't work.
- Averted and played for comedy at the same time in Rurouni Kenshin after Kenshin first meets Misao. She's been hounding him for information as to Aoshi's whereabouts, but he's been cagey about it (because he knows Aoshi's Oniwabanshu members are dead), and after they've bonded a little, Misao offers Kenshin a biscuit after having previously refused to share any food with him. Kenshin accepts the biscuit...but then immediately suspects that Misao might've laced it with truth serum. Misao snaps, "Don't eat it, then!"
- UQ Holder!: Touta accidentally eats a truth serum-laced chocolate off of Yukihime's desk, which causes some chaos around the headquarters as he begins declaring to all his friends that he loves them. Karin initially thought that she had taken the same stuff, only to be informed later that she'd eaten an ordinary chocolate.
- Subverted in an issue when Batman uses sodium pentothal on an opponent. The opponent is barely able to answer one question before passing out.
- Subverted another time when the Joker's henchmen give him some truth serum in order to get him to tell them where he kept his money. Unfortunately for them, the Joker's state of mind isn't exactly normal at the best of times, let alone under hallucinogenic drugs. The henchmen don't get anything for their efforts other than mad ramblings.
- In A Death in the Family, Batman uses sodium pentothal on Lady Shiva to get her to answer whether or not she's Jason Todd's mother, although he regrets the necessity.
- The Beezer: In a The Numskulls strip, Brainy accidentally switched Edd's truth control from 'true' to 'false'. When the other numskulls find out, he resets it to 'as truthful as can be.' Ed immediately insults an enormous violent thug.
- The French comic Captain Biceps parodied this with Wonderbra Woman's lasso forcing people to tell the truth. Unfortunately, their statements are more along the lines of "You've gained weight recently, haven't you".
- Represented realistically in Diabolik, as lowering compulsions and possible to resist. Diabolik himself was once dosed with it and his interrogators got only a glare, and a man he kidnapped for information for a theft was revealed being an undercover cop who managed to lie without getting caught.
- Truth serum's inability to make someone tell the truth is a somewhat recurring plot point, sometimes due the interrogated being conditioned to resist, more often due him having a medical condition that would kill them if the truth serum is administered, the interrogated one having been administered something that, with the help of the truth serum, ends up killing the subject mid-interrogation, having taken some drug that counters the serum's effects, and, in at least one case, Diabolik misunderstanding the information (the combination of a safe that consisted in repeating twice a sequence of numbers. When the subject repeated it, Diabolik misunderstood and inserted the sequence only once and got caged). Then there's Ginko, who is immune to truth serums due to sheer willpower.
- Natasha Morgan was another user of truth serums. She also kept around a trusted hypnotist to deal with those who can resist to the normal truth serum... In spite of not actually believing someone could resist it. She was the feared and uncontested leader of Clerville's organized crime until she decided to retire.
- A common interrogation tactic in Judge Dredd is to use truth serum. It's not the only way though since some citizens can have violent allergic reactions to it.
- In Marvel 1602: Fantastick Four, Sir Richard Reed used sodium thiopental (in gaseous form, which the victim inhales), which he's discovered over 300 years early because he's Richard Reed.
- Ms. Marvel (2014):
- In issue #12, Loki puts Asgardian truth elixir in the punch at the Valentine's Day ball. He doesn't target it or anything, just counts on that, if everybody says what they really think, he will be able to find if someone has other than relationship troubles. Hilarity ensues, and by this we mean chaos, which the local superheroine kind of takes issue with.
- In the 50th issue, Kamala teams up with Miles Morales/Spider-Man when he finds a weird purple rock. When it's activated, Miles suddenly confesses his crush on her.
- 1980's British Starblazer. P30M-90 is an extremely potent truth drug. Pentathax is used for the same purpose.
- Played with in 52 when Lex Luthor kidnaps a depowered Clark Kent and gives him an experimental truth serum which his scientists explain is a synthetic recreation of Wonder Woman's magic lasso (see below). He then asks Clark, who broke the story about new hero Supernova, why it is that Superman is toying with Luthor by pretending to be someone else. Clark, laughing madly, informs Lex that he does not know who is under the Supernova mask, but he is absolutely certain of one thing, that it is not Superman. Creator commentary in the trade-paperbacks points out that this scene, and perhaps the entire future path of DC comics, could have gone so differently if Luthor had simply known to ask the right question.
- Before that, soon after his wedding with Lois (when he was also depowered), he was kidnapped by a gangster, beaten up and drugged with a truth serum. He told them he was Superman, but the gangster refused to believe and thought the serum wasn't working. Somewhat justified, as Clark, depowered, had several hematomas and was bleeding, something Superman isn't supposed to do.
- In the Tintin story Flight 714, Laszlo Carreidas is injected with a truth serum to try and pry the number of his Swiss Bank Account from him. He, however, starts confessing to every misdeed he has ever done in his life. When Big Bad Rastapopoulos is accidentally injected with the same serum, he and Carreidas get into an argument about who is the evilest. (While no one bothers to call the winner, Rastapopoulos wins handily since he plans to murder everyone involved except maybe Allan.)
- Wonder Woman:
- Perhaps the most famous example is Wonder Woman's magic lasso, which forces others to tell her exactly what she wants to know. Originally it was portrayed without such powers, with the assumption an Amazon with her foot on your neck was a compelling enough tactic. The lasso was originally stated to have the power of forcing anyone bound in it to obey Wonder Woman's orders. This was written out, partly because it made things too easy for her. The lasso is supposed to make you tell the truth; whether or not it forces you to speak at all is unclear.
- One of Doctor Poison's many concoctions is a truth serum. She tries to administer it to Steve Trevor while interrogating him in Sensation Comics but Di switches out the syringe for one with a saline solution.
- In Wonder Woman (1942) #1 A truth serum hidden in a cigarette causes Pt. Mint Candy to give up classified information to a Mexican man collaborating with Imperial Japan.
- X-Men: Most mutants with Psychic Powers can mentally compel others to only speak the truth. During the X-Men: Schism event, Quentin Quire barges into a gathering of U.N representatives and telepathically gives them the urge to reveal their darkest secrets. These secrets range from despicable ("I beat my children because I enjoy it" and "I once shot a man just to watch him die!") to amusing ("I married a Doombot!" and "I actually love America!").
- Dick Tracy: Master Poisoner Newsuit Nan creates a totally reliable truth serum based on the blood of her target. Merely scratching a target with the toxin will place them in a trance and compel then to truthfully answer any question asked of them. She uses it to get Mr. Crime to confess that he as been cheating Panda and her out of their rightful share of the loot.
- In the One Piece fanfic And Nothing But The Truth, while the crew is on a small island, Usopp buys a gold ball that has a legend of making people speak the truth while on trial. The legends are true, as when the other Straw Hats hold onto it they are compelled to speak the truth when asked a question. However, after Luffy accidently breaks it, it breaks into dust which gets into the crew mates sans Robin and Usopp. This causes them to not only speak the truth but also blurt out random facts in non-sequitur.
- Emergency!: John Gage is given truth serum in International Incident as a foreign diplomat tries to torture him into revealing where his daughter has gone. As is common in these fics, John has a negative reaction to the high dose and is only saved because Roy and the cavalry arrive to free him.
- In the Empath: The Luckiest Smurf story "The Other Smurfette", Attorney Smurf's piercing unshielded gaze into Wonderette's eyes act as this, causing her to reveal her true identity as Hogatha the evil witch to the Smurfs at the court trial between her and Empath Smurf.
- A variation features in the Buffy the Vampire Slayer fic "False Smiles," when Xander and Faith believe that Faith is pregnant with Xander's baby, when Xander is in hospital after a fight, he lets himself get "high" on pain medication so that Faith will know he's telling her the truth that he wants to be there for her and the baby.
- A Fantastic Upheaval of Previously Held Notions: In order to see if he could be trusted, Jim spiked Strickler’s food with a truth potion. He interrogates Strickler, causing him to give an Anguished Declaration of Love before he notices, becoming violently sick trying to keep himself from confessing his more violent history.
- Pokémon Reset Bloodlines: Belladonna Tyrian, the story's resident Knight of Cerebus, has a power in her eyes that can force people to tell the truth. However, she doesn't like using it on her loved ones, considering such an act a betrayal on the level of cheating on them.
- The Star Rose describes an alien planet, Siva, where the atmosphere itself is this trope. As long as someone is breathing Siva's air, they cannot lie (although they can still be incorrect, unknowingly). This means they also cannot hide their beliefs, a shared vulnerability that encourages inhabitants to be patient and tolerant of others.
- Truth is a scourge from RainbowDoubleDash's Lunaverse lives up to its name. Not only does it force its victims to tell the truth and to keep talking, something in its makeup seems to compel its victims to tell those truths which will most hurt, enrage, or otherwise unsettle the audience. There's a reason Pokey called the stuff "truth poison".
- In chapter 2 of To Catch A Raven, Jinx is tricked into taking a truth serum while undergoing a burglary trial. She thought she was just being given a shot to nullify her metahuman powers for the trial.
- With This Ring established that Atlantis has well-developed and reliable truth compulsion magic, although the surface is still new and dubious about the idea. (Since the protagonist can't use magic, when he wants answers, he normally just resorts to orange light branding.)
- "Love is Like a Drug", a fanfic based on The Brittas Empire, revolves around Brittas unknowingly ingesting "dream flowers", a form of plant which has the effect of making whoever ingests them reveal all of their secrets to anyone. It's mainly used as a way of having Brittas reveal to Laura, who is taking care of him until the effects wear off, that he's in love with her.
- In Valiant, a British homing pigeon Mercury is given a truth serum by the German falcons who have captured him to get him to tell them the message's departure location. While he tells the truth, he still refuses to actually tell them what they want to know, and instead babbles on and on, annoying them until he accidentally reveals the location — St. Pierre. As Von Talon's minions then cover Mercury's cage, Mercury still continues to blurt out random secrets.
- The factuality of truth serums is discussed in Ant-Man and the Wasp when Sonny Burch's thugs use one on Luis. Luis, of course, is already a Motor Mouth, so it's not as helpful as Burch would like. At the end of the movie, the tables are turned and Burch and his men confess their crimes to the police under the drug's effects. The question of whether it should be considered a "truth serum" is also brought out, with Burch's thug insisting that there's no such thing and it should be called something else; he ends up coming around to Luis's terminology when he gets a dose of it at the end.
- In Barely Lethal, when Hardman injects Megan with one in the belief that she's a rogue agent, she objects that these don’t even work, but then she starts spilling her guts anyway.
- Bullshot (1983). Having kidnapped Absent-Minded Professor Fenton, the dastardly villain Otto von Bruno tries to find out his secret formula with a device designed to cause "Involuntary Lingual Slippage". After several unfortunate slips of the tongue, the device begins to malfunction, but not before the Professor is forced to admit that the formula is with his daughter who's a pain in the ARRRRRGGGHH!
- City Hunter: The Cupid's Perfume:
- Half into the movie, Ryo is injected with a very effective truth serum. He always answer truthfully to any question without lying. Hilarity Ensues
Guards: Who's there?
Ryo: It's Ryo and Kaori.
Guards: What are you doing here?
Kaori: Looking for the toilets, we're lost.
Ryo: Actually, we're trying to break into the facility.
- After Ryo kicks the truth serum's syringe at one of the bad guys, he too can't tell a lie to save his life. He accidentally reveals that he's a mole for the cops and that he was having sex with his colleague's sister — at which point they start fighting each other, allowing Ryo to escape and kick their asses.
- Half into the movie, Ryo is injected with a very effective truth serum. He always answer truthfully to any question without lying. Hilarity Ensues
- In Escape from the Planet of the Apes, Dr. Zira, a chimpanzee biologist who studied humans far in the ape-ruled future, where such things were commonplace, is given a dose of sodium thiopental by the locals after a slip of the tongue inadvertently reveals that she used to dissect human specimens. Her ramblings reveal that dissection was only the start of it, and things go sharply downhill from there. To be fair, she is warned that the truth serum will have the same effect as champagne she had earlier, which is true: she just got drunk and talkative both times.
- Robert De Niro's period spy film The Good Shepherd subverts this trope in a disturbing, graphically realistic way. Edward Wilson, the head of the newly-formed CIA's counter-espionage branch, is confronted with a Soviet "defector" who may or may not be who he claims to be. In order to determine the man's real identity, Wilson has his men administer a brutal physical beating. When they still aren't sure, they use a newly-developed truth serum called "Lysergic Acid" (better known as LSD). Rather than the above-mentioned effects of "Hollywood" truth serums, the LSD does what you would expect from reality — the man babbles like an idiot and hallucinates. Later, when the drug begins to wear off somewhat, he delivers a "Reason You Suck" Speech to his interrogators... then jumps out the window to his death. In case you were wondering, he really was who he claimed to be, making the tragedy All for Nothing, and highlighting the ineffectiveness of the so-called "truth serum". This was based on a real incident where a man who was given LSD without knowing threw himself out of a window while hallucinating. He wasn't a Soviet defector, though, but a CIA agent given the drug by his own agency to test its effect on unsuspecting subjects.
- The Guns of Navarone. When Major Franklin is critically injured, the Allied saboteur team contemplates letting the Germans capture him, but fear they may interrogate him with scopolamine and learn all of the plan. Finally, the leader uses the opportunity provided by a radio communication to feed him false "new orders", and abandon him, to the horror of Franklin's friends as they've no way of knowing if the Germans won't just torture him instead. They do torture him initially, but then resort to the drug when he appears resistant and he spits out the false orders under the drug's effect.
- Parodied in Johnny English, when the titular inept super-spy gets two gadget rings mixed up. Instead of a strong sedative, he accidentally injects a mook with sodium thiopental. The mook becomes not only truthful but extremely helpful, happily obeying Johnny's request for safe directions out of the heavily guarded building before realizing in horror what he's just done.
- Jumpin' Jack Flash. Terri works out that the code key she needs to communicate with a British agent, which is in the song Jumpin Jack Flash, actually refers to the musical key. Later when under truth serum she's asked what the code key is, she burbles, "The key is the key!", confusing her kidnapper. She then escapes, and thanks to the serum proceeds to say exactly what she's thinking to everyone she meets, including her Jerkass boss.
- In Kill Bill Vol. 2, Bill uses a truth serum, suggested to be of his own creation, called: "The Undisputed Truth", on "The Bride".
- Lady Ninja Kaede: Using a technique called "Confession from the Honey Trap", Yumeama is able to transform her vaginal juices into a confessional potion that compels any who lick it to tell the truth.
- Liar Liar has a lawyer compelled to tell the truth (almost nonstop) for 24 hours by his son's birthday wish. He can't write down lies, lie by omission, choose to remain silent when spoken to, or even ask a question to his witnesses if he knows their answer is going to be a lie. Hilarity Ensues.
- Parodied in The Man Who Knew Too Little, where the truth serum works just fine, but because Wally is actually The Fool who's been Mistaken For A Spy, his interrogators don't believe him.
- The Matrix suggests that Agent Smith injected this into Morpheus during his capture and interrogation (it's not identified by name, but it's an ominous clear liquid used during an attempt to get the access codes to Zion out of him). It ends up working fairly realistically — Morpheus is in obvious pain, but he otherwise maintains silence, lasting long enough for him to get rescued.
- In Meet the Fockers, Pam's father Jack, suspicious of Greg, injects him with sodium thiopental. Greg forgets after five seconds that he'd had a syringe jammed into his neck, and proceeds to get on the mic and spill his guts to the whole family reunion about his lust for Pam's mom, his (supposedly) illegitimate son, and Pam's pregnancy. Note that this is a reference to the lie detector scene from the first movie.
- Inspired by Liar Liar, Brazilian movie O Candidato Honesto ("The Honest Candidate") has a Sleazy Politician running for president being forced to tell the truth (along with other enforced honesty, such as refusing bribes) due to a dying wish.
- Octopussy has Bond discussing what his interrogation will involve with the Big Bad over dinner:
Bond: Well, supposing, for argument's sake, l don't feel like talking?
Kamal: Don't worry, you will.
Bond: Let me guess. Thumbscrews and hot coals?
Kamal: (insulted) Hardly. We're much more sophisticated than that.
Bond: Sodium Pentothal?
Kamal: A bit crude. Very unreliable. We prefer curare with an effective psychedelic compound. Guaranteed results.
Bond: But with permanent brain damage.
Kamal: An unfortunate side effect.
- In Odd Squad: World Turned Odd, Odd Todd fills a juice box with "truth juice" in order to make Oprah spill the location of Olympia, Otis, Oona and O'Donahue. She attempts to fight it and gives him the fake location of "the Coliseum of Autumn Sod", but he quickly deduces that she means the Museum of Modern Odd. He then asks her why they're going there and she begins to answer, but quickly covers her mouth with her hand to stop herself.
- Sally in Practical Magic finds herself mystically incapable of lying to the detective who has come to investigate the disappearance of Jimmy, whom Sally and her sister had accidentally killed. She avoids confessing by giving a series of clever truthful-but-misleading answers.
- In the film adaptation of Red Dragon, Agent Graham mentions that hospital staff tried Sodium Amytal on Hannibal Lecter to find out where he hid one of his victims. Lecter gave them a recipe for dip. Although considering his... tastes, that might have been his way of telling them without giving them anything useful.
- Subverted in Side Effects (2013). A psychiatrist gives a truth serum to a patient, but it's actually a placebo. When she acts groggy, he knows she's been faking her other symptoms as well.
- Tank Girl. The Rippers try to use nitrous oxide as one to find out if Tank Girl and Jet Girl are spies for Water and Power. It doesn't work at all: the girls only give nonsense responses.
- In True Lies, Arnold Schwarzenegger's character is injected with a truth serum by terrorists, which also allows his wife, who has also been captured, to question him about his double life as a secret agent. When the interrogator comes back, Arnie tells him all about the plan he had for escaping and killing him, reveals that he picked his handcuffs, then proceeds to do exactly what he said he would. True Lies is a comedy, so this scene is deliberately a bit over the top. Also consider the answer he gives to Helen's first question: "Are we going to die?" Answer: "Yep." (She didn't ask, "Are they going to kill us?")
- Wonder Woman: The lasso of truth naturally functions as one. Steve does his best to resist it, but can't. Interestingly, since it compels its wearer to tell the truth, in the absence of questions, they'll start talking about whatever's on their mind; Steve wraps himself with it to convince Diana he really is taking her to the front line after lying about it to his superiors, then starts rambling about what a terrible idea it is.
- Subverted in Artemis Fowl: Artemis claims that he gave Holly a dose of sodium pentothal as a truth serum, and that all of his knowledge of fairy society comes from what she told him while under its effect, but the reality is that he wouldn't dream of administering such a drug to her out of fear of giving her brain damage. His lie covers up the real source of his knowledge, while also being intended to make Holly think she betrayed her own people so she succumbs to despair while she's his hostage.
- Played fairly straight in the first book of the Blood of Kerensky trilogy set in the BattleTech universe during Phelan's interrogation by the Clans. The procedure (complete with IV drip for the truth drugs and sensors to monitor the subject's vital signs) was still involved enough to suggest that even (presumably) 31st-century medical science might be able to make this kind of thing effective, but not exactly safe.
- In The Beyonders trilogy a rare jungle cobra has venom that not only makes the victim say out loud everything that comes to mind, it makes them remember everything in perfect detail, even the Key Word after they've spoken it. After Jason is captured by Maldor his interrogators slip the cobra into his cell. In the second book Galloran uses small doses to restore some of the memories he lost during Maldor's torture sessions.
- In Bored of the Rings, a parody of The Lord of the Rings, Goodgulf the Wizard used "one of his secret potions"note to get Dildo Bugger to reveal the truth about how he obtained the Ring.
- Deathmoor has the enchanted Truthstone, which can force the truth out of literally anybody, including walking skeletons.
- In the Divergent series, the serum associated with the Candor faction is, of course, truth serum, used for trials, interrogations, and Candor initiation.
- In DocSavage Doc has occasionally used truth serum, but usually as a last resort because he's well aware of its' limitations. It does not magically make someone tell the truth, it just makes them so groggy and confused that they can't concentrate enough to think up a lie, but it's still hard to get useful information from anyone. He also has to watch the dose very carefully, as the amount needed to make it nearly impossible for them to think up a lie is uncomfortably close to the dose that will either render them unconscious or kill them outright.
- Frank Herbert's Dune universe has Verite, a will-destroying narcotic from the planet Ecaz that renders a person incapable of falsehood.
- The Elminster Series: The wizard who accosts Elminster outside his village in the hills herding sheep places him under a mind control spell, and uses it to make him answer questions truthfully. Thankfully he doesn't realize that Elminster is the son of the man he's looking for (a hidden prince who's being targeted over his claim to the throne) or he'd have been killed as well. As it is, he still orders Elminster to run off a cliff. Fortunately, Elminister has a latent magical ability he uses to save himself. Later he uses it himself on another mage to compel the truth from him.
- In Henry Seslar's short story "Examination Day", when a child reaches the age of 12, they are made to take a Government Intelligence Test. To prevent cheating the child being tested is told to drink a Truth Drug in a form of a buttermilk-like liquid which tastes faintly like peppermint.
- The Government wants to ensure that the children answer the IQ tests truthfully, and not deliberately get a lower score. This is in case any child learns what happens to those whose IQ is higher than what the Government regulation allows: they are killed.
- The Executioner:
- Phoenix Force uses scopalomine, administered by its team medic Calvin James due to the risk of possible heart failure. In one novel the prisoner has a heart condition, so they try hypnosis instead, getting enough details to work out the information they're looking for. In another, some mooks who were injured in the fight that led to their capture start babbling their cover stories after they're injected with an anesthesia. This causes Phoenix Force to realise they're professional intelligence agents who have been given hypnotically-induced cover stories in case they were injected with a truth serum.
- When Able Team are in Mexico, the indigenous guerillas they're working with capture Colonel Gunther, The Dragon of neo-Nazi warlord Unomondo, and force him to swallow their own secret truth drug. Rather than being able to answer questions, the drug makes him rant and rave for days in several languages, and Able Team has to record all this to transmit back to Stony Man headquarters to be translated and analyzed in the hope of getting something useful.
- E. E. "Doc" Smith offers us nitrobarb in the Family D'Alembert series. Nitrobarb eliminates the subject's ability to lie or withhold information, but it's difficult to use because the questioning has to be specific and directed. The other big problem is that it carries a 50% fatality rate. That's right — half the people who get given it die as a result. Lampshaded in-universe by one of the heroes, who makes it clear that generally speaking they all die, because the information extracted invariably leads to a successful conviction for treason, with the death penalty to follow. When the bad guys use it, the subjects all die because once they've milked you of what you know, you're too dangerous to leave alive.
On another occasion, the heroes capture The Dragon and inject them with a conveniently-left-lying-around dose. The information they obtain turns out to be false, but their boss is quick to point out that the dose was too conveniently left lying around, and for all they knew they were injecting them with distilled water. Later, it's discovered that The Dragon is a humaniform android, and it could have been the real thing.
- Firestarter mentions that among other things, Andy's ability to persuade people via mentally "pushing" them included the ability to get them to volunteer information they might otherwise keep to themselves, but that he had to keep from overdoing it. For instance, when chasing down the Shop agents who'd kidnapped his daughter, he was able to get a girl who'd seen them going by to reveal which way their van went by pushing her, but with just a light tap. As the novel explains, had he pushed her too hard, she would have told him (and truly believed) that the van had gone in any direction he wanted it to go, including straight up into the sky.
- Forest Kingdom: Truthspells, as they're called, are a magical version. In the Hawk & Fisher spinoff series' book 1, the sorcerer Gaunt casts one so Hawk and Fisher can question the murder suspects in his house. The spell doesn't prevent them from withholding information or answering in a deceptive way, though, so all of them get away with saying "no" when asked if they committed the murders. Turns out there are two murderers, each of whom committed a different murder; when Hawk asks each of them if they killed Blackstone and Bowman, both murderers were able to truthfully answer no.
- The Forest of Doom have an artifact called the Eye of Amber, a medallion which glows red in the presence of lies.
- Gravity Falls: Journal 3: Ford wonders if the Truth Telling Teeth have a truth serum inside.
- Subverted in Thomas Pynchon's Gravity's Rainbow. Slothrop is administered sodium amytal twice in the course of the narrative. In both cases, he is reduced to surreal babblings and squicky nightmares instead of volunteering information.
- The protagonist of one of Leo Gursky's detective comedy series is a Chew Toy Absent-Minded Professor pharmacologist. One of the substances he tested was claimed to be a "Super Truth Serum" and explicitly said to be pentothal derivative, and he has one capsule in his pocket he forgets about. Naturally, when the mafia captures him, the Mook ordered to search him is a drug addict, finds the capsule, and soon Hilarity Ensues. Still more believable than usual: apart from the nonstop talking, the Mook giggled, drooled and looked like the heavily drugged idiot he was, so even after he collapsed the boss didn't get what was going on until the protagonist explained it.
- The Harry Potter books feature a magical truth serum called Veritaserum. It's mentioned quite a lot, but the only time it's actually used was on an unconscious Barty Crouch Jr., disguised as Mad-Eye Moody. However, according to J. K. Rowling, all magical truth serums are fallible when used on a victim who is prepared for it, and its effects can be counteracted. Of course, this still makes you wonder why they didn't administer it to more unconscious people, as that worked entirely well. In the film version of Order of the Phoenix, Umbridge uses veritaserum successfully on Cho Chang, off-screen. This serves to streamline the plot, giving Harry a reason to break up with Cho without having her ultimately responsible for the betrayal. It also writes out Marietta Edgecombe, the original (serum-less) tattle-tale, as well as Hermione's "SNEAK" jinx.
- Robert A. Heinlein used this trope several times.
- "Methuselah's Children". The government uses a truth drug on members of the Howard Families to try to find out the secret of the Families' longevity. It works, but the investigators don't believe what the members tell them and assume they just know the truth.
- Friday. When Friday is captured by Boss' enemies, they use a truth drug on her to make her tell them about Boss' operations. The problem is that she couldn't tell her interrogators what she didn't know, as Boss keeps his employees on a "need to know" basis since anyone can be broken with sufficient torture. Unfortunately for Friday, the captors don't believe that she's telling the truth even after the serum, so they tortured her for information she couldn't give because didn't have it.
- In Between Planets, I.B.I. Agent Stanley Bankfield likes truth serums. As he explains to Don Harvey physical coercion can lead to the subject saying and confessing to anything if applied too zealously. The unnamed agent back on Earth who questioned Harvey in New Chicago disagreed, feeling proper application of pain would make him quite talkative while serums force him to wade through all sorts of irrelevant babble.
- In Mercedes Lackey's Heralds of Valdemar series, the Heralds have a two-stage truth spell. Stage one functions as a Lie Detector; stage two compels the bespelled person to answer any question truthfully.
- Unknown to Heralds in most time periods, the spell works by attracting a (previously bound to Heralds) non-sentient air elemental to the subject and then inducing it to possess him or her. Based on the more detailed description, stage one is actually a slightly more focused polygraph, and there's nothing to prove it lacks the same weaknesses. We tend to see the truth spell used against people lying to hide powerful and violent feelings, and the spell tends not to show up in time periods where people who can resist possession are present.
- The Hitchhiker's Guide to the Galaxy: Parodied in Life, the Universe, and Everything with a character named Prak, who was injected with too strong a dose of truth serum when asked to tell the truth, the whole truth, and nothing but the truth in court. People had to flee his illuminated ramblings or go insane. He forgot most of it (except for the bits about frogs) but was able to tell Arthur Dent where to find God's Final Message to His Creation before dying.
- The titular drug of 1940 novel Kallocain by Swedish author Karin Boye made people respond truthfully to all questions. Problem for the Universal State: It turns out everybody hates the system of government.
- In the Left Behind book Armageddon, Chloe Williams, a key member of the Tribulation Force, is captured by the Global Community, sedated, and brought to the Statesville, Illinois correctional facility in order to be given an interrogation through a truth serum injection. Thankfully, with God's help, Chloe never gives away anything concerning the whereabouts of her Tribulation Force members, though she still tells her captors the truth in that they're going to have to face God and give an account of their lives at the judgment seat.
- Magic University: A Geas can force people to tell the truth. So can the amulet which Kyle makes with regards to all mantic creatures. He makes Michael confess how he'd fed on Frost which put him in a coma this way at the end of the first book.
- Mairelon the Magician: The Saltash Set can be used a focus to cast a spell which compels someone to tell the truth. It's mentioned that this is incredibly powerful and complex magic, and nobody is entirely sure how Saltash enchanted it. At the start of the series, Mairleon uses part of the set to cast a lesser version of the spell which merely reveals whether or not Kim is lying.
- Max And The Midknights Battle Of The Bodkins: There are two separate examples in the book.
- In one chapter, Mumblin' the wizard casts a truth-telling spell on Millie's Bodkin to get her to tell them the Bodkins' plans. She passes out before she can tell them anything useful.
- Later, when the Midknights are in the Land of Knot, Kevyn, Millie, and Sedgewick inform them that the Bodkins have been giving them a truth serum to try and get them to tell them about Byjovia. However, it doesn't work on humans. It does, however, work on Bodkins.
- In Pact, being magically enslaved can have this effect if the master so wishes. When Rose is unwillingly bound by Conquest (who unfortunately avoids asking her specific questions that would leave her some Exact Words wriggle-room), he commands her to "tell me everything you don't want me to know", forcing her to explain exactly how she and her allies were planning to outsmart him.
- Parker: In The Sour Lemon Score, Rosenstein and Brock use a truth serum on Parker to find out what he knows about George Uhl. Parker later uses the same serum (which he discovered when her searched Brock's apartment) to interrogate Uhl about the location of the money.
- Tamora Pierce:
- No one can tell lies in close proximity to the griffins in the Tortall Universe. Their feathers have associated properties like dispelling magical illusions. However, truth spells can be fooled fairly easily, even when you don't have magic.
- Pierce’s Circle of Magic books also have truth spells; most mages that can use them specialize in vision and related matters. ("See" the truth, you know.) Tris's teacher Niko is a highly respected one, which comes in handy when Tris's student is being held for "questioning" in Tharios.
- Quarters: A major plot point of Sing the Four Quarters is that nobody can lie to a bard under interrogation: they have the ability to magically compel the speaker to tell the truth regardless of their preference. Except nobody really quite believes it when Pjerin, Duc Ohrid, is revealed by this compulsion as a traitor, because it just plain seems out-of-character. Turns out part of the Frame-Up involved planting what amounts to a post-hypnotic suggestion that forced Pjerin to respond in a self-incriminating manner to the Bard Captain's legally prescribed question.
- In the first Quiller spy novel, the title character is injected with a drug designed to make him high and therefore talkative; they get some facts out of the subsequent Word Salad, but not enough. Quiller does reveal too much about his obsession for a girl he's met, however, so they decide to use that angle to force his co-operation.
- The Rifter: Fathi, a drug used repeatedly in this novel, fits almost all the aspects of this trope. It makes a person feel relaxed and happy and willing to answer anything, and they also find themselves telling the truth even when they don’t intend to. Sometimes it doesn’t get the desired result because of a too literal answer, such as when John is asked where Ravishan is and says he doesn’t know (well, he doesn’t know exactly where, does he?) but more often it works all too well. This is how John lets it slip out that Lady Bousim has been practicing magic and gets her burned as a witch, cementing her son Fikiri’s hatred for John.
- The Sandokan novels have the youma drink, also called "the lemonade that loosens the tongue": a drink made of lemon juice, opium and sap from a youma plant (an unspecified member of the sansevieria genus), it gets the drinker too high to care he shouldn't answer the questions he's being asked, even insulting the questioner if the revelations are about a plan to harm them. First shows up in The Mystery of the Black Jungle, when Bharata prepares it and Macpherson tricks Tremal Naik in drinking it, with many others (including the Thuggee and James Brooke) knowing how to prepare it.
- Spider Robinson wrote a short story, "Satan's Children", about the social effects (highly disruptive but mostly good in the long run) of a drug that made people tell the truth while under the influence — and continue to do so afterward as they realized that total honesty was less of a psychic burden than maintaining false facades. It wreaked particular havoc among political and religious leaders (although it didn't break all of them).
- Schooled in Magic: Spells which force people to tell the truth exist, and they're used in court cases, ensuring that innocents are not convicted.
- Semiosis: Stevland helps a murder investigation by growing fruit that disinhibit the eater, encouraging them to speak truthfully about whatever's on their mind. Tatiana can resist the urge somewhat because she knows about it, whereas the others are unaware that they're being drugged.
- Bruce Coville's The Skull of Truth has the main character come into possession of a talking skull that forces him to speak only the truth. He finds out, though, that there are different levels of truth (apparently jesters and poets are better at telling the truth more obtusely than others), and ultimately comes face-to-face with Truth him/her/itself, who describes itself as both destroyer and healer. At the end, the protagonist is gifted with the ability to compel people to tell the truth, whether they want to or not.
- So This Is Ever After:
- Heart's Truth pollen makes people reveal who they desire at heart.
- Bethany's Magic Music is also capable of complelling people to tell the truth.
- Lois McMaster Bujold's Historical Fantasy novel The Spirit Ring features a magical truth spell, in the form of a saltcellar (its physical form directly copied from the famous Cellini Salt Cellar). Anyone who places pepper onto their tongue from the saltcellar’s pepper receptacle is magically compelled to speak the truth.
- Combined with a Brown Note in the Star Trek: New Frontier novel The Quiet Place. The Redeemer Overlord, along with a killing word, has a truth-telling word, that compels a person to spill his guts. In fact, it makes the victim tell every truth he's ever known, and then kills him. Then it's subverted in the fact that the victim was trying to get them to stop torturing another victim for information...but they keep going anyway because, even though he did tell the truth, the other victim still could be hiding something.
- Stardust: Madame Semele tricks the Witch Queen into eating food laced with an herb called Limbus Grass, which makes the Witch Queen talk about her quest to acquire the Star. A similar sequence happens in the film version between their film counterparts Ditchwater Sal and Lamia.
- Sword of Truth: This is the purpose of the Confessor's touch. It causes the person touched to feel love toward the Confessor so overwhelmingly that they will tell them anything which they did, or do anything else asked. Thus, it's used to ensure a person accused of capital crimes is really guilty, gaining true confessions.
- In Violet Eyes and the sequel Silver Eyes, they have what's called TrueFalse, administered through a patch on your skin. While it doesn't force you to tell the truth, it does force you to talk, and will make you sweat if you tell a lie. While it can be used in court, a person can refuse to have it used on them.
- Lois McMaster Bujold's Vorkosigan Saga has a truth drug called fast-penta, which when it works properly fulfills this trope perfectly. Inducing honesty is not actually its primary effect, though: what it does is make the subject want to be helpful, allowing the interrogator to suggest that it would be helpful if they would answer a few questions. The distinction is illustrated in Ethan of Athos, in a sequence where fast-penta is used to interrogate a character who is actually entirely ignorant of the subject at issue; instead of explaining that he can't understand the questions, let alone answer them, he attempts to help out by tacitly translating them into questions he can answer and answering those instead, to the confusion of his captors.
- However, as fast-penta is a drug, not everyone reacts the same way. Most exceptions are fatal allergies. People whose work involves sensitive or classified information can have the allergy artificially induced unless their lives are deemed more important than the secrets they know. Bujold often uses artificial allergies to keep the characters from learning too much too soon. Another exception to the norm is Miles Vorkosigan. Due to his screwed up body chemistry, fast-penta induces a temporary mania in addition to the typical long-windedness. He uses this to his advantage, forcing himself to be discursive and bouncing off the walls reciting Richard III until his interrogators give up and put him back in his cell (And he still doesn't shut up until he finishes reciting the entire play, to his cellmate's discomfort).
- Fast-penta also removes its subject's inhibitions, making them voice whatever is on their mind. So when Ekaterin is under fast-penta, she talks about her sexual curiosity about Miles, to his embarrassment.
- In The Wheel of Time books, the Aes Sedai have an artifact called the Oath Rod, which binds the will of one who makes an oath while grasping it. Each Aes Sedai before becoming a full sister must swear three oaths using the Oath Rod, one of which is never to speak a lie. However, they tend to become skilled at (and widely distrusted for) making misleading statements while never saying anything technically untrue.
- During Worldwar: In the Balance the aliens try their truth drug on one of the protagonists, but all it does is make him rather giggly. With some difficulty, he manages to keep his cover story straight. The aliens don't know this, so they believe his story that he's an innocent civilian and let him go.
- This may be an illustration of what happens when you try to use truth drugs in real life — they work by lowering inhibitions (which sometimes helps), not by creating some kind of magical compulsive honesty.
- The fact that it was originally designed for use on aliens with reptilian/dinosaurian physiology (the Race, Rabotev, and Hallesi) instead of mammalian probably didn't help. The Race has had over 50,000 Earth years to work on it so it may work perfectly on themselves and subject species. The alien Fleetlord and Senior Shiplord are later seen discussing that the drug has not been working as well as it should be.
- In the X-Wing Series, it is mentioned that CorSec officers undergo a chemical interrogation as part of their training. When it was done to Corran Horn, he ended up confessing to every childhood misdeed committed in his entire life, which would have been amusing even at the time had the interrogator not provided a transcript to his father (a fellow officer). While also amusing and somewhat disturbing to the reader, the existence of not only such drugs used by a police force but stronger ones available to groups like, oh, the Empire, makes one wonder about how Leia managed to hold up to an interrogation by Darth Vader, when the arguably less-vicious Ysanne Isard had methods that would (with only mild exaggeration) have Corran "spilling secrets his mother had forgotten while he was in the womb".
- 24 has occasionally used "hyoscine pentothal" in the past (a fictional substance whose name is taken from the names of two real substances).
- Agents of S.H.I.E.L.D.: In the pilot, Agents Coulson and Ward bring Skye in for interrogation. Coulson tells her about the top-secret truth serum SHIELD has access to — then injects Ward with it, and leaves the room, letting Skye grill Ward and satisfy herself that SHIELD is actually on the side of good. (And, in the process, learn embarrassing details about Ward.) In a later episode, Ward tells Skye that there never was a truth serum, and it was all a ruse to get her on board the team. Well, someone's lying, that's for sure. Given that Ward later turns out to be a HYDRA agent, it probably was fake.
- Alex Rider: When Dr Greif finds out Alex isn't who he says he is, he Straps Him To An Operating Table and drugs him. Alex is able to resist, partly by confusing the experience with the previous kidnapping and shouting gibberish related to that.
- Averted in the pilot of Alias. Sydney gets captured and injected by a foreign agent, but while it makes her talkative and a little hyper, the only "information" she gives up is actually a Stealth Insult.
- In 'Allo 'Allo!, Herr Flick of the Gestapo often uses truth serums in his interrogations. They are extracted from various animals, and have corresponding side-effects (the serum made from bats makes Mimi sleep while hanging upside-down, while one made from fireflies causes Smallhausen's butt to glow).
- Arrow: In "The Promise", Professor Ivo uses sodium pentothal on Oliver Queen. However, Sara Lance has worked up a picrotoxin to counteract the effects of the barbiturates in the sodium pentothal and given it to him beforehand. He intentionally gets captured and proceeds to feed Ivo false information.
- The Barrier: During some interrogations, agents of the Police State are shown to inject people with a substance that seemingly makes it much harder for them to keep their mouths shut.
- Blake's 7:
- In "Pressure Point", this is used to get a rendezvous code out of a Rebel Leader. As Servalan has a personal grudge against the rebel, she deliberately gives her a lethal overdose.
- In Season 4, Pylene-50 is introduced being used for this purpose, though it's main use is to enable the easy conquest of planets by removing the urge to resist. It works by blocking the production of adrenaline, so the recipient doesn't get angry and placidly goes along with anything suggested to them — in this case answering questions about his mission and the resistance cell he's a part of.
- Bones: Zack intends on injecting himself with truth serum so Brennan will believe he’s not the serial killer they’re after. She points out that it won’t work the way it does in fiction, though. Zack acknowledges it but says it’ll lower his inhibitions more and he’ll be less likely to lie. He doesn’t get to actually do it, though, as the real killer shows up.
- Burn Notice has a relatively realistic go at showing the real-life effects of a 'truth serum'. James injects Michael with a hallucinogenic drug that makes it harder for Mike to lie and/or withhold information.
- Charmed (1998):
- The episode "The Truth Is Out There And It Hurts" has Prue casting a 24-hour "Truth Spell" which results in anyone who is asked a direct question having to answer with the truth. Unfortunately, it also meant if anyone asked one of the sisters a question, they would have to answer with the truth.
- In "Necromancing the Stone", Paige later uses the same spell, and the effects are very different. The "applies to everyone under this roof" and "the caster must answer honestly" aspects are dropped. The boyfriend she used it for (to see how he'd react to the family secret since the spell comes with automatic Laser-Guided Amnesia) provided some extra information he's married but was also able to lie. He just had to quickly correct himself.
"I was going to tell you... no, I wasn't."
- Counterpart: Howard Alpha is interrogated by Ian using a machine that can detect lies. As he honestly doesn't know the answers (they think he's Howard Prime), Ian concludes he's gotten better with deceiving it.
- In Doctor Who, the Plains of Trenzalore are covered by a "truth field" meaning that "no-one can lie or stay silent". Which makes it the perfect/worst place to ask the ultimate question: "Doctor who?" When the Doctor and Clara finally arrive there, they ask a local couple if they don't find the truth field a problem. One says yes and the other says no. Of course, the Doctor finds all sorts of ways around that over the course of the episode.
- The Dukes of Hazzard had an episode where Roscoe returns from a police convention with, among other things, a syringe filled with truth serum. Boss Hogg sits on the syringe about halfway through the episode, injecting himself with the serum. Hilarity ensues when he can't stop telling the truth, including calling the IRS and confessing to cheating on his taxes for several years.
- Played fairly realistically in Farscape. When Aeryn is captured by the Scarrans and tortured for information, she is injected with truth serum (from a massive syringe): the drug merely lowers her resistance to questioning while also causing physical pain, disorientation, and eventual unconsciousness. After several rounds of torture and several lies, she finally tells the truth — though by then, she's barely able to speak coherently.
- Admittedly this didn't stop her from getting sarcastic with the torturers during the first session:
Aeryn: No, don't use that, I won't lie to you. I'll just tell you what you want to know.
Battle Axe Nurse: You wouldn't lie to me?
(She injects Aeryn at the shoulder.)
Aeryn: Yes, of course I'd lie to you, you stupid bitch!
- The Scarrans are also mildly psionic and can use their powers to force the truth out of people, though it can still be an evasive half-truth. In the same series of episodes, when John is captured attempting to free Aeryn, he claims that he decided to because Aeryn was prettier than the nurse and that once he had freed her he was going to have lots of sex and babies with her.
- Admittedly this didn't stop her from getting sarcastic with the torturers during the first session:
- An interesting example cropped up on Chuck. In the episode "Chuck Versus The Truth," the villain of the week uses a poison that has the side effect of inducing truth-telling tendencies in its victims. Chuck, Casey, and Sarah are all ultimately administered the drug. Since this is a comedy, it's mostly played for laughs, as when Casey admits Sarah is better at picking locks than he is. But at the end of the episode, Chuck asks Sarah if she has any real feelings for him. Her answer: No. At the very end of the episode, it's revealed Sarah has built up an immunity to truth serums.
- Get Smart:
- Maxwell Smart is drugged and ordered to tell his interrogators "everything you know". Naturally, this results in a seemingly endless stream of trivia, including multiplication tables.
- In another episode, Max is tasked with drugging a suspected enemy spy with a truth pill, while she gives him a sleeping drug. A Poisoned Chalice Switcheroo later, he first tells everything to the sleeping spy, and later yet is talking to his boss...
- Inverted in "The Groovy Guru" when Max is given 'lie pills' in case he gets captured and interrogated. Max accidentally swallows his pill too early and Hilarity Ensues.
- In an episode of Hercules: The Legendary Journeys, the heroes were searching for the Sword of Veracity, which made whoever held it incapable of lying. Iolaus and the Girl of the Week found themselves in a cave full of swords, so Iolaus grabbed the first sword he could and said she was the ugliest girl he'd ever seen, explaining that the Sword should not allow him to lie. The duo then proceeded to do the same with each sword in turn ("My name is Hercules and I have two heads." "This is a rutabaga.") until she found the right one through a Cassandra Truth moment, warning Iolaus of the monster behind him.
- Downplayed in Hogan's Heroes in "At Last, Sergeant Schultz Knows Something": The Heroes are trying to find the location of a laboratory being used for atomic research, and Schultz (who is going to be assigned to guard the lab) is the only one who knows that they have access to. They dose him with sodium pentothal under the guise of an inoculation for his new post. As sodium pentothal is a low-level anesthetic and not a magic drug like the Heroes expect, Schultz doesn't just tell them, but he acts dazed and dopey (rambling, breaking into song) and gives them enough hints during a conversation with LeBeau about the food there that they can figure out where the lab is.
- In an episode of Human Target, the plan is for Ilsa to give the villain of the episode wine dosed with such a chemical so he'll tell them his password. Played with, in that to convince him that it isn't poisoned, she also drinks it herself, after which she tells him the whole plan.
- I Dream of Jeannie plays with this. Tony gets sick of Jeannie doing him favors and commands her that the next time he asks for anything, she deny it. He ends up getting kidnapped by terrorists but due to his previous command, Jeannie can't directly rescue him. The terrorists try to give him truth serum to make him talk, so Jeannie casts a spell on him that forces him to speak in a different language when under the effect of the serum.
- An episode of The Invisible Man has Claire accidentally injected with an experimental truth serum which causes constant babbling, paranoia, and loss of inhibitions. It's played for drama when she struggles to resist revealing secrets about the Quicksilver program and laughs when she starts trying to violate Darien.
- In an episode of Law & Order: Special Victims Unit, the use of truth serum on a teenage girl creates Fake Memories of her being raped by her father. The ensuing False Rape Accusation leads to escalating tragedy.
- Legend of the Seeker: This is the purpose of the Confessor's touch. It causes the person touched to feel love toward the Confessor so overwhelmingly that they will tell them anything which they did, or do anything else asked. Thus, it's used to ensure a person accused of capital crimes is really guilty, gaining true confessions.
- An episode of Lois & Clark has the villain capture the inventor of a teleporting machine and inject him with a serum that makes him more talkative.
- Played straight on Lost when Sayid is restrained and given an unnamed drug by members of the Dharma Initiative, who believe him to be a hostile spy, and informed that he will have no choice but to answer their questions truthfully. When he does so, eventually revealing that he is from the future, the interrogator concludes that he used too high a dose.
- The Magicians (2016):
- Quentin drugs Dean Fogg to find out who Eliza really was. Dean Fogg admits that, out of forty time loops, Quentin has managed this in 27 of them.
- Eliot drugs the drinks of his inner circle to find out who's responsible for turning half of the castle's inhabitants into rats.
- One of the powers of the second Golden Key is that anyone holding it is compelled to tell the truth — while holding it, Rupert's boyfriend was compelled to confess his love.
- In The Man from U.N.C.L.E. episode "The Foxes and Hounds Affair'', Napoleon and Illya are injected with truth serum to make them reveal the location of a device wanted by THRUSH. Napoleon, who is out of the loop this episode and legitimately doesn't know, just starts acting drunk; but Illya is compelled to give up the information after minimal resistance.
- Humorously used on Married... with Children after Kelly gets bitten by a swarm of poisonous Samoan beetles during a commercial she's filming for an extermination company. Bud discovers that the Samoan people use the bugs' venom to create a truth serum, and Kelly ends up repeatedly telling the truth at the worst possible times.
- The Middle Man: The Middleman sets off a truth bomb to get Pip to confess he copied Wendy's paintings. Everyone else in the vicinity starts spontaneously confessing embarrassing truths. Wendy tries to take advantage of the truth bomb to find out the Middleman's name, but he manages to dodge the question by giving her an honest answer that says nothing.
- In the M.I. High episode "Spy Animals", a truth serum causes the teachers to start blurting out what they really think about the students and other members of staff, and causes Daisy to tell her friends that she is really a spy. They think this is a story to cover up the fact that she is going out with Blane. Blane attempts to get Daisy to say what she really thinks about him while she is still under the influence, but Lenny gives her the antidote before she can reply.
- NCIS: In "Truth or Consequences", a terrorist leader injects DiNozzo with a concoction of his own design consisting of sodium thiopental And Some Other Stuff, causing DiNozzo to give a recap of the events leading up to his capture.
- Person of Interest:
- In "Aletheia", a government agent gives Root alternating injections of a stimulant in one arm and a sedative in the other. This is a real technique developed by the CIA MKULTRA project. It failed spectacularly on Root and apparently wasn't so hot for the CIA either (it was supposed to induce a cooperative trance, but as often as not the subject would just fall asleep).
- In "4C", Shaw spikes Hersh's drink with scopalomine, which has the additional benefit that he won't remember what happened. Hersh not only reveals the information Shaw wants, but the cold-blooded Implacable Man also reveals his concern that his former protege whom he tried to murder is being treated well by her new employer. D'awwww...
- In the Quantum Leap episode "Star Light, Star Bright", Sam leaps into an old man obsessed with UFOs who is dosed with sodium thiopental by government Men in Black. Instead of telling them what his host knows about UFOs, he starts revealing top-secret information about himself and the Quantum Leap project. The Men in Black just assume it's gibberish and that they've given him too high a dosage.
- In possibly an Internal Homage to the previous example, Quantum Leap (2022)'s protagonist is injected with sodium thiopental and he too begins babbling the truth about his identity and time traveling. In this case, the serum was administered by a Mad Doctor who assumes Ben to be genuinely insane — and thus a perfect subject for his horrific experimentation.
- Red Dwarf: Lister injected the prison warden with sodium thiopental, which apparently caused him to come to a meeting late explaining that he had been shagging the science officer's wife and he hadn't had time to change out of his Batman costume.
- One episode of Sliders has the gang land on a world where everyone has to wear "truth collars." While not quite a serum, the effect is the same.
- In the Smallville episode "Truth", Chloe is exposed to a gas that makes others unable to lie to her. The only person able to resist is Clark, who doesn't answer when asked about his secret.
- Star Trek
- Subverted in the Star Trek: Deep Space Nine episode "Little Green Men" when Quark is injected with 6 doses of sodium thiopental, with no effect. But that's a Ferengi's metabolism for ya. Quark ironically is only too willing to talk, to stop these mad humans from jabbing him with sharp needles.
- In Enterprise, Vulcans are apparently resistant or disciplined enough to defeat such measures. When a villain is interrogating T'Pol about the possibilities of time travel, she is able to respond using what is technically true: "The Vulcan science directorate has determined that time travel is impossible."
- Enterprise also revealed that the Andorrians have an interrogation device specifically designed for Vulcans which removes their emotional control, thereby making them a lot less capable of deceitfully telling technical truths the way T'Pol does. The one time we see it in action, however, Shran is using it on Soval to confirm that he really is telling them the truth about a planned Vulcan invasion. When Shran still Won't Take "Yes" for an Answer even after Soval has suffered a total emotional breakdown, Soval angrily berates him for being stupid and insists that he crank his device up further until he's convinced.
- Star Trek: Deep Space Nine also revealed in some episodes that while the Vulcan mind-meld can be used to extract information from unwilling subjects, some of the Cardassians (Gul Dukat, for one) had a conditioning technique to block the Vulcans from using it on them. Also, one alien government had developed a means to alter and block its agents' memories while they were working undercover so that they would actually believe they were who they were making themselves out to be if anyone tried using any of these methods on them, meaning their interrogators would get nothing useful out of them even though they were being completely honest.
- The "Chain of Command" two-parter of Star Trek: The Next Generation has the Cardassian interrogator of the captured Picard use truth serum while torturing him. Unfortunately for the Cardassians, Picard doesn't have the information they want (because his superiors weren't dumb enough to send him on a dangerous spy mission with current intel on fleet deployments). The torturer himself doesn't really care, he just enjoys his work and breaking people, leading to the 2 + Torture = 5 ordeal.
- In the Star Trek: Discovery episode "That Hope is You, Part 1", Michael Burnham is subjected to some kind of truth serum by the guards in the holo-trading station. It's not clear if her physiology is different to what they're used to or if, as one of the guards suggests, the other one's been experimenting with the formula, but it initially has no clear effect, then sends her to sleep for a few seconds. When she wakes up, her thought processes are sufficiently scrambled that what she says is true, but doesn't make a whole lot of sense unless you know her story already.
- In Stranger Things 3, Steve and Robin are captured by Soviets that have infiltrated the Starcourt Mall and beaten for information as to who sent them there. They repeatedly (and truthfully) insist that no-one sent them, that they just work for the mall itself. The Soviets, assuming Steve and Robin are lying to them, shoot them up with a severely disorienting drug in hopes that they won't have the presence of mind to keep their cover stories straight. The General isn't happy when Steve continues to insist they just work at the mall, though Steve eventually spills that they found their lab due to intercepting their cover frequency by sheer luck and that Dustin and Erica escaped and likely told the authorities about the Soviets. It winds up making Steve and Robin puke their guts out after being severely high for hours.
- Supernatural has an episode in which anyone who asks for the truth gets it, in full, from everyone who talks to them. In this case, it's not due to a truth serum but a truth curse.
- Terminator: The Sarah Connor Chronicles: During the episode "Some Must Watch While Some Must Sleep," Sarah gets injected with something, and her assailant tells her she'll be talking within three hours.
- The Time Tunnel. In "The Day the Sky Fell In", Doug and Tony reveal that they are time travellers after being given truth serum, leading their captors to believe they must be professional spies who have been conditioned to spout nonsense when drugged.
- Cole is given truth serum in the Tracker episode 'Dark Road Home'. He snuck into a mental hospital to find a dangerous fugitive who was hiding out there in the body of a psychologically troubled human. The nurses give Cole the serum to see if he'll tell something, but it backfires. He starts talking about the alien stuff and just seems to be saying more crazy things.
- Tropical Heat: Nick is injected with one in the episode “Double Switch” and questioned.
- The Twilight Zone (1959) had an episode ("The Whole Truth") in which a used car salesman buys a car its previous owner claims is haunted and finds himself supernaturally being forced to tell the truth, which is especially inconvenient in his line of work. Eventually, a local politician (who for obvious reasons doesn't want the car for himself either) helps him fob the car off as an all-American souvenir to a foreign politician who happens to be in town for a visit: Nikita Khrushchev.
- The Twilight Zone (1985): In "Examination Day", Dickie Jordan is given a truth serum to ensure that he answers all of the questions on the government intelligence test as truthfully as possible.
- In the UFO (1970) episode "Computer Affair", the "GL-7 serum", one of the "new anodynes", is used on a captured alien at Straker's orders to lower his resistance so he'll talk. Unfortunately, it kills him instead, due to either his different biology or him somehow committing suicide to prevent himself from talking.
- In V: The Final Battle, the hero Mike Donovan is injected with an alien truth serum and fulfills this trope completely. This is an alien formula, so... Though the initial injection apparently wasn't strong enough.
Diana: What color is your hair?
Donovan: Blue. [Diana injects him again]
- Willow: The truth plums growing in the Wildwood have this effect on people eating them, making them always tell the full truth (although they're able to briefly hold this back).
- Gorillaz's music video for "Aries" ends with Murdoc preparing to inject 2-D with truth serum while on a peaceful motorcycle ride with him (implied to be because he wants answers as to what exactly 2-D and the other band members think of him now after the events of the "Désolé" music video). However, Russel's intervention ensures that Murdoc doesn't learn a thing that he wanted to from the endeavor, and it's likely that doing such an awful thing has only served to make his relationships with everyone else worse than they were before.
- The Smyrk's song The Ballad of Fletcher Reede is about a man whose girlfriend put sodium thiopental in his Coke, and how he insists that she doesn't want him to tell the truth when she asks him loaded questions.
- In Celtic Mythology Lugh Lamfada's sword, Fragarach, had this as one of its main functions, earning it the name, "The Answerer." Similar to Wonder Woman above this was accomplished by holding it to a subject's throat.
- The Men from the Ministry:
Lennox-Brown: Morning Mildred! Glad I'm late, gives me less time in the office.
- Two Soviet spies mistake General Assistance Department as the head of British Intelligence, and use their new experimental truth serum on Mr. Lamb in order to get information.
- Another one ends up being injected to all civil servants and government officials instead of the annual flu vaccine, leading to the entire Whitehall speaking nothing but the truth with hilarious results.
- XERRD of Dino Attack RPG developed a substance called Veritaserum, named after the potion from Harry Potter, which shuts down the neurological pathways necessary for lying.
- Battlelords of the 23rd Century supplement Lock-N-Load: The Battlelord's War Manual. Truth serum puts the recipient in a highly suggestible state for two hours and is 95% effective in getting them to tell the truth.
- Dungeons & Dragons:
- The spell Zone of Truth prevented anyone in it from knowingly lying. However, they are not compelled to answer and can be evasive if they wish.
- For more fun, the 3rd Edition of Oriental Adventures (based heavily upon Legend of the Five Rings) has an improved version called "Truth is a Scourge" that also forces the victim to answer any question asked. Considering this is set in a land where honor is extremely important, it's rather common for victims to say something that insults themselves or their lord and be forced to commit seppuku to save face — which is the whole point of the spell.
- Magic items
- Both 2nd and 3rd Edition had a Potion of Truth that forced anyone who drank it to speak the truth. The 3rd Edition version allowed the drinker to make a saving throw to refuse to answer a question.
- Module Assault of Raven's Ruins. The Sceptre of Truth forces anyone to speak the truth for as long as they touch it.
- Ring of Truth. If a person wearing the Ring tries to lie, they speak the literal truth instead.
- Ring of Truthfulness. The wearer must provide full and completely true answers to any questions asked of them for as long as the ring is worn.
- White Wolf's Vampire: The Requiem has several methods of forcing somebody to tell the truth, from the gentle to the awesome. On the gentle side, "Majesty" can compel somebody to want to confess their innermost secrets to you. On the awesome side, the "Liar's Plague" causes bugs to swarm out of a subject's mouth when they lie.
- Changeling: The Lost likewise has a low-level Goblin Contract named Sight of Truth and Lies that lets you automatically tell when somebody is telling a lie. The downside is, if you lie while using it, you'll automatically believe anything but utter bullshit is true when coming from the speaker's mouth.
- There are a few in GURPS; the Truth potion from Magic as well as Sodium Pentothal and Sodium Amytal in High-Tech. There's also the standard "Compel Truth" spell and an equivalent psychic ability. Again, despite the name, it only prevents victims from lying (if it works...) It does not force them to say anything.
- Paranoia supplement Acute Paranoia, section "Better Living Through Chemistry". The drug Telescopalomine actually works realistically. Clones under its effect answer questions reflexively (not necessarily truthfully) and will be agreeable to anything told them. Internal Security uses it for interrogations.
- Rifts (and the rest of Palladium Books Megaverse Setting) has the Words of Truth spell, which compels you to answer questions truthfully, but you get a save for each question.
- The Traveller universe has Truth Drug. The recipient answers questions truthfully for two minutes, then falls unconscious for an hour and takes moderate damage.
- The Conspiracy Theorist in Citizens of Earth learns to use truth serum as one of his attacks... by drenching the enemy with a bucketful of it. Since this guy is rather mentally unstable, it's unknown if the thing he uses is actually truth serum or something else, so it has no effects. It does, however, count as an Aqua-Element Attack.
- Concentration Room begins when a group of kids visiting their parents at a drug research facility are exposed to a botched batch of the truth serum Pinenut.
- Hidden City has a potion called Drops of Truth, which can make people reveal secrets. Unusually, this potion works by applying the potion on an item related to the secret the user wishes to know about and demand the suspect to reveal what they know. In "Guises of Evil", Rayden uses this potion to interrogate Marquise von Hart on the whereabouts of the key she stole from Mr. Black, but he ends up using the remainder of the potion to question Black about the dubious secrets he's keeping.
- Played straight in KGB but with a slight twist. The serum used by the protagonist at one point is a new prototype and has very severe side effects. Namely, it's lethal, so PC must extract all necessary information quickly.
- Discussed in Metal Gear Solid: after Naomi is captured as a spy, Campbell mentions that the interrogation (already under a severe time constraint) isn't going well, and they don't have any sodium pentathol on the base. It's doubtful it would work on its own, but the implication is that they're going to employed Enhanced Interrogation Techniques.
- This was also used decades earlier on "Huey" Emmerich in the The Phantom Pain. Problem is he managed to convince himself of his own lies so it's not very effective.
- In Persona 5, Joker is forcefully injected with one by the police, most likely to make him more susceptible to the request to sign his confession, though they do resort to outright assault and threats to get him to do so should he refuse. Notably, Sae calls the validity of Joker's statements into question multiple times during the interrogation, wondering if he's hallucinating Which, if you get one of the bad endings, he is or outright lying, and actually taking him more seriously when it started to wear off. The serum nearly screwed up a straightforward plan to foil an assassination attempt directed at him made beforehand since it's wrecked his memory in several points which results in him nearly forgetting there was a plan, the identity of the Traitor and what he had to do, resulting in an insane Gambit Roulette. He barely manages to pull through and perform his part of the plan which saves his life and fakes his death.
- Subverted during the first Splinter Cell game; at the end of a mission, you are required to knock out a security guard between your extraction vehicle. Two of your allies keep him occupied by talking about interrogation techniques, the one mentioned involves a 'truth serum' that leaves them too drugged out to actually give up anything useful when they talk... but also too drugged out to remember what they actually said. You then convince them they already told you what you wanted to know, and thereby manipulate them into actually telling you.
- Twisted Wonderland: Jade's unique magic "Shock the Heart", but it comes with several drawbacks: it can only ever be used once on a given target, and can be resisted.
- Near the end of Ultima VII, you acquire a magical artifact that can force the Fellowship's members to tell you the truth.
- ETU - Animated Stories: Lydia's divorced husband refuses to pay her child support, so she decides to spike his and his finance's drink to make them confess their crimes and secrets. They were arrested.
- In episode 6 of Helluva Boss Blitzo and Moxxie get captured by demon-hunting government agents, and after annoying the heck out of them during a "regular" interrogation the agents instead flood the room with a gas that causes them to blurt out secrets they've been keeping from one another, and then they start hallucinating.
- Ballerina Mafia:
- A variation; a tomb-robber is cursed to have an illusion of the mummy following him around, constantly announcing what he's thinking to all in earshot.
- In another comic, a government agency accidentally dumps experimental truth serum in the water supply.
- In Girl Genius, the Sturmovarus family slips a truth serum into Agatha's soup. She had previously been hiding the fact that she was a Spark or a Heterodyne; the truth serum causes her to lose all inhibition and blurt out her entire backstory in one continuous spiel over three pages, then compliment her dessert, then fall face forward into it before declaring "You're very cute!" to Tarvek as he cleans her up and his father wryly admits that perhaps a bit too much serum had been put in her food.
- Grrl Power: The villains injects a captured Halo with a truth serum to get inside information on ARCHON, except it backfires spectacularly. As it happen, using a truth serum on a Motor Mouth Cloudcuckoolander with ADHD only results in an absolutely non-stop blabbering, stream-of-consciousness run-on sentence devoid of any useful intel (except maybe for the dating status of some members), and it threatens Sidney with passing out from lack of breath.
"What the hell did you inject her with?"
- A Maximumble strip features a dentist injecting their patient with truth serum before asking "Have you been flossing?"
- In one The Non-Adventures of Wonderella comic, Hitlerella tells Wonderita that she has been injected with truth serum in order to tell Hitlerella the nuclear codes. Instead, Rita starts babbling inanely about anything that comes into her head, concluding that she's uncomfortable with silence because she thinks everyone is judging her. Then Hitlerella's hench-being says he's ready to inject her with the truth serum.
- Gunnerkrigg Court: Word of God tells us that Antimony's contract of ownership over Reynardine means that he can't intentionally deceive Annie. He can, however, withhold information and refuse to answer questions.
- In The Order of the Stick, the zone of truth spell works exactly like this. Taking inspiration from Burlew's work, zone of truth has the same effect in Murphy's Law.
- String Theory (2009): A shady prison psychiatrist forcibly injects Dr. Schtein with sodium thiopental and LSD to make him more "chatty" in his sessions. Instead it takes him from disjointed rambling to a hallucinatory breakdown in minutes.
- In Schlock Mercenary drugs with an amnesiac effect are a standard part of interrogations. If that doesn't work they can try mind-ripping, which quite literally takes the brain apart to get at its contents.
- In Super Therapy!, Wonder Woman's lasso is used as such, as usual. Quite efficient to make a cheating boyfriend fess up.
- In The Adventures of Jimmy Neutron, Boy Genius episode "Grumpy Young Men", one of Jimmy's inventions turns him, Carl, and Sheen into old men. When they're about to age into dust, Jimmy convinces them to go back through the device with offers of prune whip on the other side, and when they return to normal, Carl is eating a bowl of what he thinks is prune whip but is actually Jimmy's experimental truth serum. He begins confessing secrets such as having stolen Jimmy's toast the other day and his mother being 42.
- Batman: The Animated Series:
- In "The Strange Secret of Bruce Wayne", Hugo Strange mentions that he interrogated Alfred offscreen about Bruce Wayne with one, and it took him a while to crack. Alfred apologizes to Bruce for not being able to resist, but Bruce doesn't blame him.
- The episode "The Lion and the Unicorn" has a double subversion: Red Claw injects Alfred with a truth serum to learn the launch codes for a British missile, but rather than submit to her demands, Alfred simply begins hallucinating and babbling incoherent rhymes. After hours of this (and constantly building frustration), Red Claw realizes that the nonsensical babble actually is the launch code. Also the source of one of Alfred's best lines:
Alfred: You'll get nothing but gibberish out of me, madam. [singing] I come from haunts of cootenfern and knicker sudden Sally. Uh...dee-dum dee-dum dee-dum dee-dum, and bicker down the valley.
Red Claw: [shakes her head] And people wonder why no one takes Britain seriously anymore.
- One rather brilliant episode, "Never Fear", later on had Scarecrow make a gas that rendered people subjected to it incapable of fear. While this didn't exactly stop them from lying, it pretty effectively removed their motivations for keeping any socially inconvenient truths to themselves, leading them to do and say all kinds of things they normally wouldn't for fear of the consequences. When Batman himself fell under the influence of the gas, we learned, among other things, that his code of honor against killing is driven largely by fear, either fear of regret after the fact, or possibly the fear that once he kills one person, he will go on to kill again and again.
- The Fairly OddParents! episode "A Bad Case of Diary-Uh" has Vicky twice use it on Timmy.
- In the "Bottomless Pit" episode of Gravity Falls, Mabel gets tired of Stan's constant lying and turns to the journal for a magical solution: Truth Teeth. This turns out to be a horrifying mistake, as without a filter, Stan complains about his aging body, insults his customers (more than usual), and starts confessing his many crimes to the police, forcing Mabel to tell a lie herself in order to save him.
Sheriff Blubs: So after further investigation, turns out there is no "Dr. Medicine" in Gravity Falls!
Deputy Durland: You better have a durn good explanation for this.
Stan: Oh, and I do! You see, I lied to you. In addition, I've been parking in handicapped spaces, shoplifting fireworks, and smuggling endangered animals across multiple state lines. Also, you're fat.
- In the Kaeloo episode "Let's Play Spies", Mr. Cat injects Kaeloo with a truth serum. Eventually, all of the main four get injected with it and blurt out personal secrets to each other.
- An episode of Kim Possible had Kim hit by a Truth Ray, with the full effect of the entire trope: not only could she not lie, but she was also compelled to say anything and everything, in far more detail than was needed. She confessed a crush to members of the sports teams, and told her dad's bosses everything her dad found annoying about them (one tells very bad jokes, one won't stop talking about his home country, and one obviously wears a wig). She ended up covering her mouth to suppress the truth compulsion. Ron, who was hit by the same ray, instead becomes more confident and popular. He does things like admitting to Mr. Barkin that not only did he not read the assigned book, but that it was boring and dumb, earning Barkin's respect by stating an opinion he'd secretly shared, and winning the heart of a beautiful girl by talking about the beauty of her eyes.
- An episode of the Men in Black cartoon had Jay accidentally injected with a truth serum, which resulted in him speaking everything that popped into his head. He was perfectly capable of telling a direct lie unless asked a direct question-when first asked by some Muggles what's going on in this whole crisis here, he gives them one of the standard-issue weird-but-believable cover stories. When one of the bystanders finds himself impressed by this, he says, "Wow! Really?" and Jay admits that no, it's actually a cover story to hide the fact that he's a government agent meant to protect them from this threat and cover up the fact that it was ever there.
- This is the main point of the episode "Truth Ache" of The Penguins of Madagascar.
- In an episode of Rex the Runt Bob and Rex start drinking what they assume is a truth serum (it was actually orange juice) and, presumably due to their minds making it real started admitting to old lies they'd told in the past, revealing secrets and plenty of assorted lampshading ("Why do you wear that eyepatch anyway? You have two eyes!"). However, at the end of the episode, Wendy pours the real truth serum down the sink and we cut to a pair of rats in the sewer who start doing the same thing! Also, earlier on, Vince stumbled upon the real serum and drank some of it. It caused him to see two creepy live-action guys with cameras, presumably the show's animators, and start babbling "The horror...the horror..." Yes, it's a weird show.
- Phineas and Ferb: Dr. Doofenshmirtz plans to force the people to tell the truth with his Tell-The-Truth-inator which he built in the image of Abraham Lincoln. It works as intended, but what he does learn from the afflicted isn't interesting at all. He does hit Suzy with it during a scuffle with Perry by accident, who then flat-out blurts her attempts to make Candace look bad all morning.
- In an episode of The Smurfs, Gargamel captures the Smurfette and prepares a truth serum to force her to reveal the Smurf village's location. Unfortunately for him, Azrael steps on the potions book and accidentally turns the page to a potion of compulsive lying. In another episode, Papa Smurf gives a Snake Oil Salesman an ointment that acted like this to prevent him from ever lying about his products.
- An episode of Star Wars Rebels shows that the Interrogation Droid seen in A New Hope uses this to get information. The screaming is apparently because the needle is very big, and the injection itself rather painful. The effect is depicted fairly realistically, with Hera becoming very blunt and losing much of her vocal filter. The effects wore off pretty quickly, most likely due to the adrenaline caused by subsequent combat burning it out of her system so that when she finally confessed her feelings for Kanan, she was completely sober.
- The Simpsons: In "Selma's Choice," Princess Opal accidentally confesses that her Love Potion is just corn syrup and rubbing alcohol and will likely make the user's hair fall out. This, however, demonstrates that the potion she'd actually ingested — her truth serum — really does work.
- Varian from Tangled: The Series manages to render a truth serum from a potion that inverts a person's most prominent personality trait.
- The T.U.F.F. Puppy episode "True Spies" has the conflict start when Dudley Puppy and Kitty Katswell eat waffles that were topped with Keswick's Truth Syrup. This leaves them unable to lie and involuntarily thwarting their own efforts to sneak up on D.O.O.M. by blurting out the truth behind their deceptions immediately after saying them. Things get worse when Dudley ends up revealing to Snaptrap the existence of a T.U.F.F. invention called the De-Threadulator, which Snaptrap then plans to use to destroy all fabric in Petropolis so that everyone in the city is left naked and too embarrassed about their nudity to stop him. Dudley and Kitty ultimately save the day when they take an antidote and trick the villains into eating Truth Syrup-topped waffles to get them to reveal how the plan can be stopped.
- Subverted in "The Incredible Mr. Brisby" episode of The Venture Bros., when Dr. Venture is given a truth serum to reveal what his research on cloning has yielded. Apparently, it has an antagonistic reaction with one of the multitude of pills Venture is taking, and makes him think he is some sort of country milkmaid and recite lines from Rear Window (which might actually be a realistic reaction).
- In Young Justice (2010), Zatanna casts a spell during the interrogation of Professor Anthony Ivo, forcing him to blurt out the location of his rival's lab. He even glances down when his mouth moves against his will.
- Happened to the first child who eventually accused Michael Jackson of sexually molesting him. Initially, his father Evan Chandler had been accusing Jackson of sexual abuse of his son, but the son, Jordan, himself wouldn't support the allegations. Eventually Evan, being a dentist, took his son in to pull a tooth and used sodium amytal as the sedative for the procedure. Sodium amytal is known "on the street" as a truth serum and is generally illegal to use in dentistry. Psychiatrists know the drug better for rendering users susceptible to suggestion and being able to induce false memories. It was during this event that Evan claims Jordan first spoke of being abused by Jackson, and it is after this point he began supporting his father's story.
- The closest things to a real truth serum we have... are alcohol and marijuana. Project MKULTRA found this out the hard way when they discovered that while the more "interesting" mind-bending substances they tried out on unsuspecting subjects were more likely to make such subjects want more substance rather than brainwash them, the FBI had actually gotten actionable intelligence on a bank heist by lacing a captured Mafioso's cigarettes with THC. Just as they were to be declassified, the substances were discreetly experimented with by a handful of individuals and spread through colleges, and... you know... it led to telling another kind of truth.
- Hypnosis was once thought to work like this. There is still a persistent myth that it provides perfect and accurate memory recall. Unfortunately, hypnosis is just as unreliable as any other real-life "truth serum," and the human brain is very prone to modifying or making up memories — this might be said to be the main issue with the very concept as a whole: it assumes that human memory is infallible. (However, it has been shown to be somewhat reliable in increasing someone's memory and recall of some kinds of information when objective proof of what the subject is trying to remember is on hand.)