The psychological thriller has become one of the most compelling and commercially successful genres in recent literature. A psychological thriller in literature is defined as a book that makes the reader feel afraid, tentative, and expect bad things to happen to them. It features the characters’ psychological and emotional states, as well as suspense and tension. Psychological thrillers inquire into the instability of perception and moral ambiguity, and provide a breeding ground for the exploration of complex identities and power dynamics. In the late decades, psychological thrillers have increasingly focused on female characters, not only as victims but also as perpetrators, through demand long-standing gender norms ingrained within crime fiction. This conversion follows broader socio-cultural transformations swayed by feminist theory and expanding understandings of gender, agency, and transgression.