“Narrative”, as stated by Bordwell and Thompson (B&T), is the “way that humans make sense of the world”. We understand narrative situations, or “chain of events” as cause-effect relationships occurring in time and space.
In our daily life we might refer to narrative as “story”, however a difference between both terms must be made in order to avoid confusions. According to B&T, as viewers we are able to infer information that might not be explicitly presented, and in order to describe how we are able to make such connections they suggest an examination of the terms plot and story.
Plot is then the term used to describe all that is present in the film, both visible and audible. It includes, all the story events that are depicted in a direct manner and all material that is extraneous to the story world.
In order to make their point B&T introduce the term diegesis, which is a term used originally in literary theory and encompasses the world in which the story takes place. The term is important to recognize, as we need to understand that there are certain elements that appear in the films’ plot that are sometimes external to the diegesis. We call such elements non-diegetic.