Most of us have encountered someone like this: a friend who turns on you without warning, a colleague who quietly undermines your work, or a partner who initially seemed perfect but later revealed a much darker side. While we might call them difficult, toxic, or even a “bad apple,” personality researchers have a more specific term: the “dark tetrad.” Guest: Leanne Ten Brinke - associate professor of psychology at UBC Okanagan and directs the Irving K. Barber Faculty of Arts and Social Sciences‘ Truth and Trust Lab. Learn more about your ad choices. Visit megaphone.fm/adchoices