Operator

 The film opens with the sound of different emergency calls - this helps provide context for the audience as well as demonstrate how stressful the environment is. The use of cinematography makes what would otherwise look like a fairly boring phone call seem as action packed as what's happening on the other end of the line.  There are a lot of close up shots of the operator's face as she talks to Gemma. The fact that her face takes up most of the screen creates a sense of claustrophobia, like there isn't much space to breathe, which is reflective of what Gemma is going through. As well as this, there is also a medium close up of the operator between two monitors, making it seem like there are walls closing in on her, making her feel trapped. This illustrates the idea that the operator is empathising with Gemma. When Gemma goes upstairs, the operator and the audience is unsure if she has made it. Tension is built not only by the dialogue but through the ringing sound getting gradually louder. This is helped by the side profile shot of the operator as it makes it seem like she is talking to nobody, further alluding to the fact that Gemma might not have survived. After Gemma has been saved, the sound of shouting and sirens coming from the other side of the line stop abruptly, leaving an empty silence. This sudden stop and the sound of the operator breathing allows the viewer to calm down, as she is doing. We from a close up to a medium close up to further emphasise the break from the action. Soon after, the operator accepts another call and all the noises of the computers and the people talking start up again, almost exhaustingly. This helps illustrate the stressful environment that the operator works in, and the unfinished second call makes it seem like her work never stops.