Psychological contracts – an individual’s perception of mutual obligations between him/herself and an organisation – form a powerful lens to understanding employment relationship. While the consequences of the psychological contract are well-documented, its antecedents are not fully understood. Research suggests that personality traits, operationalised using the Big Five taxonomy, can explain the type of psychological contract that employees develop. We extend this research by developing a theoretical model that relates three maladaptive traits – the dark triad of personality: Machiavellism, narcissism, and psychopathy – to the content of employees’ psychological contracts. We propose that employees with high scores on these traits tend to develop transactional as opposed to relational psychological contracts. Moreover, we introduce five mediators to explain these relationships: the norm of reciprocity, careerism, perceived organisational support, trust, and interpersonal conflict. Finally, we offer an explanation for earlier suggestions of curvilinear effects of the dark triad traits. We reason that psychopathy and narcissism negatively relate to self-control which, in turn, moderates the relationships between the dark triad traits and the six mediators in our model.