Sin City -

- Genre conventions -

Film Noir: 
Lighting (high contrast/low key) -

The assassin's face half lit face within the first scene - good or bad? (Reference to Cold War - trusting no-one, corruption)
Kevin's face in darkness - showing he is evil. 

Cynical Protagonist -
Marv to probation worker, "Hell is waking up everyday and not knowing why you are here."
adjective1 believing that people are motivated by self-interest; distrustful ofhuman sincerity or integrity : her cynical attitude.• doubtful as to whether something will happen or whether it is worthwhile : most residents are cynical about efforts to clean mobsters out of their city.• contemptuous; mocking : he gave a cynical laugh.

Femme Fatale -

Goldie sleeps with Marv for protection from Uncle Roark. (Using her body to get what she needs, using the male protaganist's weakness against him.) 
Nancy - Post modernist femme fatale. Uses her innocence not her body to get help (mostly when she is a child.) 

Comic Book:
Super human strength -

Marv escaping from police - smashing threw car window screen and swinging from the banister with ease.

Exaggerated diegetic/non diegetic sound -

Marv's punches.
Gunshots and explosions. 
These are a result of post production add are added after filming to exaggerate the action elements of the film.

Propp character roles - 

John Heartigan = hero. 
Nancy = heroine. 
Bob = sidekick. 
Junior = Villain.