The mise en scène means 'placing on stage' in french.it originated in theater.In a film it has a wider meaning to it as it means everything in a composition of a shot, even the composition itself. it is referring to the framing, movement of the camera and characters, lighting,set design, gen eral visual environment, sound, and spacing.
i think mise en scène is an effective way of creating an illusion and making the scene more interesting and it is adding to the atmosphere.