TY - THES N2 - The aim of this research is to uncover Libby Day?s imbalanced system of personality and its impacts, and also the types of her ego defense mechanism. This research is a qualitative research. The source of data of this research was taken from Gillian Flynn?s Dark Places published in 2009. The data taken from the novel were in the form of particular expressions related to Libby?s imbalanced system of personality and her defense mechanism. During this research, the researcher read and re-read the text, collected the data, categorized the data, and analyzed the data taken from Gillian Flynn?s Dark Places. The data were analyzed by using Freud?s psychoanalysis theory that focused on the imbalanced system of personality and ego defense mechanism. To obtain the trustworthiness of the data, the researcher used peer-debriefing method. The findings of the study show that Libby Day?s imbalanced system of personality is caused by the domination of her superego. It is triggered by three factors: her father, the traumatizing death of her family and how the society treats her after the death of her family. The results of Libby?s domination of superego are feelings of guilt and anxiety. The types of Libby?s ego defense mechanism are repression, denial, projection, rationalization, and displacement. Libby mainly shows the usage of ego defense mechanisms to forget the death of her family and ignores the guilt of putting her brother into jail. Keywords: Dark Places, Gillian Flynn, Psychoanalysis, Imbalanced system of personality, Domination of superego, Ego defense mechanism Y1 - 2017/10/18/ A1 - Annas, Andraina PB - Universitas Negeri Yogyakarta ID - UNY54131 M1 - skripsi KW - Dark Places KW - Gillian Flynn KW - Psychoanalysis KW - Imbalanced system of personality KW - Domination of superego KW - Ego defense mechanism AV - restricted TI - THE ANALYSIS OF LIBBY DAY?S IMBALANCED PERSONALITY AND HER EGO DEFENSE MECHANISM AS SEEN IN GILLIAN FLYNN?S DARK PLACES UR - http://eprints.uny.ac.id/54131/ ER -