This document discusses the narrative structure of psychological thriller films. It notes that these films often feature characters with mental disorders and non-linear narrative techniques like flashbacks. Specifically, it analyzes how Identity and Fight Club are examples of "thriller portmanteau films" that tell interrelated stories through multiple characters and timelines rather than a single linear plot. While employing unconventional structures, these portmanteau films still incorporate traditional thriller elements like mysteries, clues, and suspense to engage audiences.