We have all encountered them: the coworker who constantly moves the goalposts, the friend who thrives on chaos, or the date who makes you feel like you are losing your mind. Dr. Leanne ten Brinke, a psychologist at the University of British Columbia, calls these “Poisonous People.” Her new book, released this March, dives into the “Dark Tetrad”—narcissism, psychopathy, Machiavellianism, and sadism—and offers a practical “10-second test” to help you spot a manipulator before they drain your spirit.
Use Open-Ended Questions to Break the Script
Most of us fall into the trap of asking “yes or no” questions, which are an easy out for a liar. Instead, try using “what” or “how” probes. When you ask someone to describe a situation in detail—like asking what exactly was discussed in a meeting they claim to have attended—a truth-teller will naturally overflow with specifics. A fabricator, however, will often freeze or offer vague “filler” answers. This creates a “cognitive load” where their brain struggles to invent facts as quickly as you ask for them.
Throw a Curveball to Trip Up Rehearsed Lies
Liars are often great at rehearsing a script, but they rarely prepare for the mundane details. If you suspect someone is being dishonest about their background or a specific event, ask an unexpected question. For example, if someone claims they worked at a certain office, ask them what the best lunch spot was within walking distance. A real former employee will have a favorite sandwich shop or a specific complaint about the local cafeteria. A faker will mumble, stall, or look physically pained as they try to guess a believable answer.
Ignore the Body Language Myths
Forget what you’ve heard about shifty eyes or fidgeting hands; science shows these aren’t reliable indicators of a lie. Skilled manipulators can look you dead in the eye while spinning a total fantasy. Dr. ten Brinke suggests focusing on the words instead of the gestures. Watch for chronic vagueness, over-simplicity, or a sudden change in their speaking pace. Your ears are much more powerful lie detectors than your eyes when it comes to protecting your peace from toxic orbits.
Why This Works: Deceit is the Common Thread
While narcissists and “Machiavellians” have different motivations, they all share a reliance on manipulation to get what they want. By recognizing these verbal patterns—the dodge, the stall, and the vague generality—you aren’t just being a detective; you are setting a boundary. This isn’t about giving someone a clinical diagnosis; it’s about identifying a pattern of callousness. Once you see the cracks in the story, you can choose to step back and keep your energy for the people who actually deserve it.Do you think these “gut feelings” we get about certain people are actually our brains subconsciously picking up on these verbal inconsistencies? Tell us in the comments below.