Dr. Albert Wilson documents his experiences as the primary physician of an adolescent girl who, over the course of four years, displayed more than a dozen distinct identities. Each persona was unique in its memories, mental capabilities, physical disturbances, aesthetic abilities and moral development. The first secondary personality appeared while the girl suffered from an "attack of meningitis." The physician hypothesizes that vaso-motor changes in the brain may play a central role in the etiology of this case of double consciousness. Finally, while considering the violent and socially deviant nature of some of the patient's personalities, Wilson examines moral and legal responsibility as it relates to the acts committed by individuals with dissociated identities.