The document discusses different narrative structures and theorists. It explains linear and circular narrative structures, as well as Aristotle's and Freytag's plot structures. It then discusses several narrative theorists including Vladimir Propp who identified character roles like hero and villain, and Tzvetan Todorov who proposed narratives follow a structure of equilibrium, disequilibrium, recognition, resolution, and restoration of equilibrium. Finally, it argues Todorov's theory links well to horror narratives and that Roland Barthes' theory of enigma also applies when the protagonist must solve a puzzle to survive, as seen in films like Saw.