Narrative Structure and Theory

Narrative is defined as "a chain of events in a cause-effect relationship in time" (Bordwell & Thompson, Film Act, 1980) 

Conventional Narratives are structured in five stages according to Todorov:

1. A state of equilibrium at the outset. This the point where the film is in its normal state, and problems have not been presented. 
2. A distribution of the equilibrium by some action. The problem within the film is presented.
3. Recognition that there has been a disruption. The characters recognise the problem.
4. An attempt to repair the disruption. The characters begin to resolve their problems. 
5. A reinstatement of the equilibrium. The atmosphere returns to normal.

An extremely similar structure can be found within film trailers, and they usually appear in the same order. However, in a film trailer stage 5, where there is a reinstatement of the equilibrium is left out, this leaves the audience wanting to see what happens at the ending of the film, and how the characters resolve their problems.