The relationship among three personal fables ("omnipotence," "invulnerability," "personal uniqueness"), narcissism, and mental health variables was assessed in a large, cross-sectional sample of adolescents drawn from Grades 6 (n = 94), 8 (n = 223), 10 (n = 142), and 12 (n = 102). Participants responded to the New Personal Fable Scale, the Narcissistic Personality Inventory, the Children's Depression Inventory, three indices of suicidal ideation, an inventory of delinquent risk behaviors, the Global Self-Worth scales from the Self-Perception Profiles for Children and for Adolescents, and two subscales from the Self-Image Questionnaire for Young Adolescents. The results showed that omnipotence and narcissism strongly counterindicated internalizing symptomatology, and were robust predictors of positive mental health and adjustment. Invulnerability was strongly associated with risk behaviors. Personal uniqueness was strongly associated with depression and suicidal ideation, a relationship that increased with age. Hence, personal fable ideation is a multidimensional construct with differential implications for adolescent mental health. Adolescent fables of invulnerability and personal uniqueness are risk factors for externalizing and internalizing symptoms, respectively, while "narcissistic omnipotence" is associated with competence. Implications for theory, practice, and future research are discussed. (Contains 2 tables.)