The character and casting conventions of a thriller film/trailer are that they often consist of a battle between the protagonist character and the antagonist, when there is a disruption in the equilibrium. Then the story shows a chain of bad events building tension and suspense for the climax. The aim of the protagonist is to restore justice, while the antagonist seeks to destroy it. The protagonist is often a brave male who seeks to restore the equilibrium. The antagonist will have a hidden identity that the audience will uncover as the film progresses. Often the antagonist goes out for revenge from a past event. The storyline will be designed so the audience will think that it can happen to them, which will make them feel scared. I looked at the casting conventions of particular films too see the conventions in casting a thriller film.