There exists a prejudicial influence in the way that psychological thrillers depict their mentally-ill subjects. Accordingly, this creative project closely examines scenes from the following four seminal films: Psycho, Taxi Driver, American Psycho, and Joker -- each of which exemplifies four psychosocial themes that have a dominant presence within the ‘psycho-thriller’ sub-genre. These include themes of toxic masculinity, urban corruption, social class, and latent trauma. Each of these are then discussed in terms of their presence and meaning within the genre -- particularly the method in which they reinforce prejudicial understandings of severe mental illness (SMI) despite reflecting the dominant beliefs of medico-scientific communities, criminological theorists, and psychoanalytic schools of thought of the eras in which they were released. Given that these theories continue to inform the public’s understanding of severe mental illness (SMI), this thesis seeks to expose how the enduring presence of these psychosocial themes within the ‘psycho-thriller’ subgenre has conflated the presence of mental illness with criminal disposition. After discussing the representation of these themes in each film, this paper highlights how psychological thrillers may function as instruments of advocacy for mental health in spite of their ‘horrific’ elements, and provides examples of how other entertainment media have helped normalize neurodivergence in a neurotypical society.