Basic Trope: A character can, through magic or otherwise, tell when people are lying.
- Straight: Alice confronts Bob about an issue. He tries to lie his way out of it. Alice tells him that she knows he's lying, because she can pick up on some slight cues.
- Exaggerated: Alice is hypersensitive to the various little cues that tell people when someone's lying. She can pick up on even the slightest falsehood or metaphorical truth.
- Downplayed: Alice will be the one to notice anyone lying, but one many occasions no one including her will notice the lie.
- Justified:
- Alice has received extensive training from an intelligence agency to see facial tics that reveal deception.
- Alice is a Super Soldier who can literally smell when someone's lying.
- Alice is a telepath.
- Alice has robotic eyes that can detect changes in body temperature and blood pressure associated with deception.
- Alice knows Bob's poker face, they're roommates after all.
- Alice is a Consummate Liar herself and knows from experience.
- Inverted:
- Alice is completely unaware of the concept of lying, no matter how obvious.
- Anyone can tell when Alice lies.
- Bob is such a convincing liar that even lying detectors (living or not) can't tell if he's lying or not.
- Subverted:
- Alice just made a lucky guess - she really couldn't tell if Bob was lying.
- Alternatively, Bob is autistic, has a disorder (e.g. Avoidant Personality Disorder), or else he's a plain old fashioned Cloudcuckoolander, which affects his body language. Alice cannot read him accurately.
- Or Gregory assumes everything people say is a lie unless proven otherwise.
- Double Subverted:
- She just said she was guessing to keep her powers a secret.
- Bob overcame this years ago through therapy, he just has a very good poker face and uses his (now redundant) disorder to explain it. Alice eventually spots his "tells".
- Parodied:
- Alice is completely taken in by Bob's obvious lies, until he tells one incredibly well-shrouded untruth. It's this that causes Alice to start doubting him.
- Alice can tell whether or not anything Bob says is true, even when he doesn't know.
- Despite knowing all the signs of lying, Alice herself's a Bad Liar.
- Zig Zagged: Alice just made a lucky guess. Oh wait, she made that up. Or did she?
- Averted: Alice's powers of observation are no more or less than anyone else's.
- Enforced: "We need to show that this character is hypersensitive!"
- Lampshaded: "I knew you were lying because you were sweating, you refused to blink, and you didn't make eye contact!"
- Invoked: "I know he's lying because Charlie told me the truth, but this is a great opportunity to scare him out of ever lying to me again!"
- Exploited: ???
- Defied: Bob is able to explain away every argument Alice makes. He stutters because of diction. He refused to blink because he had something in his eye. He didn't want to make eye contact because Alice made him nervous. He was sweating because the room was warm.
- Discussed: "Wow, she's good. I hope I never marry someone like that."
- Conversed: "How did you know? Are you one of those spooky Human Polygraphs they have in spy movies?"
- Deconstructed:
- Alice's ability to detect lies causes her to break down - she's so good at reading people that she can literally glean everything about them, including things she didn't want to know.
- No one wants to be around Alice because they don't want a friend who's able to detect lies that well.
- Through her power, Alice finds out that the world is full of liars and that everyone, regardless of their reason, lies about something at some point. She eventually loses faith in the world and humanity. In her eyes, the world we live in is a Crapsack World built on lies and falsehoods.
- Reconstructed:
- Alice gets over this flaw and uses her powers for good. She realizes white lies make life easier for people, and learns to tell the bad ones apart.
- Alice stops telling people she knows they're lying, because people have started being very careful around her and she never finds anything out.
- After some much-needed Character Development and gaining a new perspective on life, Alice now understands that not all lies are inherently bad or malicious in nature. She still dislikes lying in general, but she also begrudgingly admits that lies can sometimes be useful and do some good under the right circumstances. Alice now has a bit more hope for the world and humanity.
I knew you were lying because... well, just go to Living Lie Detector and I'll tell you why.
