Using five independent non-clinical cross-cultural samples (total N = 3649; overall Mage = 29.31; 31% male and 69% female), this study explored the extent to which Dark Triad traits were indirectly associated with symptoms of psychopathology through mental toughness. Although Machiavellianism and psychopathy have not been studied extensively in this context, previous research (both cross-sectional and longitudinal) reports that grandiose narcissism increases mental toughness contributing indirectly to positive outcomes such as lower anxiety, stress, and depression. Accordingly, this study examined Machiavellianism, psychopathy, and narcissism in the context of mental toughness and psychopathology. A particular focus was placed on investigat...