Conventions of the Thriller

LOW KEY LIGHTING

Dark lighting in scenes is essential in setting the genre and tone in a thriller. It also contributes to the mystery of the film. 

MYSTERY/ENIGMA

Mystery instills a sense of suspense in the viewers giving them continued interest in the movie, by keeping them asking questions.

SUSPENSE

Suspense is a factor that is compulsory for thrillers. It ensures the audience have intrigue in the film. Suspense is usually created from the mystery involved in thrillers.

SLOW/REALISTIC BUILD UP

The build up in thriller films makes sure the plot points of the aren't revealed too early in the movie and keep the viewers wanting more.

ISOLATED SETTINGS

Giving the film a setting that is secluded and desolate increases the mystery factor of it due to the area being lesser known and away from other parts of the world.

ACTION (sometimes)

Though it's not mandatory, some thriller films make use of action sequences in order to make it more flashy and exciting to watch.

DIEGETIC SOUND OF BREATHING

Diegetic sounds of breathing, especially when the source of the breathing is unknown, is very common in thrillers. It is a convention that, though, is not ubiquitous, is very effective in giving the atmosphere more tension.