A repertoire of elements are the key features that are repeated throughout a certain genre. Each genre has its own specific repertoire of elements, which help to distinguish it from other genres. They all come under these categories:
Iconography : Different genres of films contain different visual as well as audio images that become iconic and recognisable with the genre. For instance Icons for the Western genre of films includes ten gallon hats, spurs, horses, saloons, guns, jails, and the badge of the sheriff.
Style : Refers to the way in which the items in iconography are presented, such as camera angles, editing lighting as well as the use of colour.
Settings: Genres has a distinct location as well as time period. ( e.g horror - dark places such as isolated houses and forests )
Narrative : this refers to the story structure as well as specific narrative devices, which genre employ. Narrative theories explain the underlying structure, which inform the way audiences make meaning from narratives.
Characters : Narrative is usually developed through characters and their functions. Some characters are so closely associated with genre that they become generic types. ( e.g horror - demons, monsters, killers and creepy children )
Christian Metz's genre theory

- Classical-structuring on narrative, mainly victorious/define era. (e.g Dracula - 1931 )
- Experimental-This is where the genre is established and experiments which different sceneries and scenarios. ( e.g scream )
- Parody- Conventions have been reformed where thriller scenes and movies incorporated comedic effects watering down expectations of the film. ( scary movie 4 )
- Deconstruction- Where other genres elements and sub genre's are introduced. The thriller genre has now evolved into a stage where hybrids are evident. The thriller has now fused with several other genre creating sub-categories the most established being sci-fi/thriller or horror/thriller hybrids. ( e.g - The sixth sense )