Opening Sequence

The opening sequence is an integral part of a film.  It foreshadows main events, sets the time and place, can introduce characters, and indicates the type of thriller.  It mainly does this through the mise-en-scene (showing location, signifiers such as weaponry, people such as detectives or spies), but also through the other three technical areas.  Camera, through close-ups, dutch angles, or extreme close-ups, create meaning and can distort the images in an interesting way, creating tension or confusion, both integral to the creation of a thriller.  Sounds are can create meaning as well, through non-diegetic sounds such as tense or frightening music and sounds effects (shatter, high-pitched noises) or synchronous diegetic sounds to match the thriller-type action on screen (explosions, gunshots, screams).  The editing can be very effective in creating a thriller atmosphere in the opening sequence, by quick cuts, the text of the credits, flashbacks, different washes (black and white, shatter effects...) as editing creates meaning by putting the images together.

The surveillance camera wash gives a trapped/watched feeling, creating tension and suspense. (Film: Quarantine)

The main title sequence indicates the types of characters and the setting of the film.  It creates verisimilitude in the opening minutes of the film.  This is done through editing for perspective and camera angles, which may indicate what type of character we are seeing (spy, police officer, victim...) by showing things from high angles (looking down as antagonist) or low angles (victim) or through eyeline match (a police officer seeing a crime).  Sound can characterise through non-diegetic music, for example dark, loud music for an antagonist.  Sound also sets the scene, for example using ambient sounds of wind or people talking to show either a remote place or a city.

The ambient sounds of wind on a mountain are interrupted by an explosion!