This document discusses the genre of thriller films. It defines thrillers as films that use suspense and moods like anticipation, anxiety, and terror to entertain audiences. It notes some early influential thriller films from the 1920s and discusses Alfred Hitchcock as a pioneering thriller director. The document also outlines some common thriller subgenres, narrative conventions like twists and cliffhangers, typical visual elements like moody lighting and weapons, character archetypes of protagonists and antagonists, and filming techniques used to make audiences feel uneasy.