A trailer is a short promotional film for a feature-length film that is intended to
attract the attention of a potential audience. For this purpose, the trailer
provides insights into the most exciting and/or funny scenes
and shows sequences from the film in a concise form. The scenes are usually shortened and usually not shown in the order that they appear in the film itself. The main purpose is to get the audience as enthusiastic as
possible about the film in the shortest possible time.
Just like the main film, most trailers follow a three-act structure. They start with an Exposition
(Act 1), in which the characters and the core of the plot are introduced. In the second act, the story picks up speed and intensifies to a dramatic climax. The third and last act is often effectively accompanied by an impressive motif from the film music (for example, a piece of music with a high recognition value or stirring orchestral music) and often consists of a quick montage of the most impressive and emotional scenes of the film. Sometimes the most popular actors in the cast are shown at the end.
Because a trailer is an extremely powerful way of telling the story, there is often a powerful off-screen
narrative voice that tells the audience the key message or ideas in the film and provides important explanations of the images.
In 1913, the advertising manager Nils Granlund
produced the first trailer ever shown in an American cinema. It was a
short advertising film with which he wanted to promote the musical The Pleasure Seekers
, which had its premiere on Broadway on 3 November 1913.