Tension within Thrillers.

https://www.youtube.com/watch?v=UhqwLgyzy38

We can tell tension is created during this opening sequence because of various reasons. Firstly, the music continues to build through out the sequence, giving the feeling that something is going to happen and gets the audience on the edge of their seats. We also see a wide shot of a young girl in a swimming pool. The water looks very choppy like a rough sea, this is pathetic fallacy, which suggests something bad is about to happen. 

 Next we see an underwater shot of the girls body, this tells us that the girl is very focused on what she is doing and is not aware of what is going on around her. This builds tension as we know something is going to happen but know she is not aware of it yet. While she is under water, we also hear the sound of a heartbeat which builds more tension.

The slow motion shot that happens at 0:55 also helps to build tension as it slows everything down making it longer to watch when the audience are desperate to see what is about to happen.

Next, we see a man (we can tell that he is a man from his body shape) entering the room. This builds a lot of tension because firstly, it is an enigma,  we don't see his face and secondly the audience know the girl is unaware of everything going on around her so we know she doesn't know he is there which makes us panic and feel scared for her.

The sound of a heartbeat is then repeated as the man walks closer to her adding suspense. It then goes into slow motion again as the girl comes up from underneath the water and realises the man is there, her mouth drops and the music drops telling us the climax has been reached.