This research details the changing ways in which young people of different ages differently warrant the conviction that, notwithstanding evidence of good and bad behaviours, selves can be understood as unified across the various roles and contexts that they occupy. Canadian adolescents and young adults were asked to explain the apparent disunity of self implied by good and bad behaviours manifested by the fictional character Dr. Jekyll and Mr. Hyde, themselves and familiar others. Age-graded differences were observed, where young people described themselves as increasingly multiplicitous and context dependent as they grew older. This developmental trajectory is understood to represent an emerging desire to imagine one's good behaviours as internally motivated, and one's bad behaviours as externally provoked. (Contains 1 figure and 5 tables.)