The opening to 'Zodiac'

In the opening of Zodiac, we see a slow tracking camera rolling through a dark street, with quite a few people around and lots of fireworks going off. The shot comes from inside a moving vehicle, in which we discover a girl is driving. The slow, long shot makes us wonder whats happening, we are left slightly confused and want to know more. A young man gets into the car with what looks like, his girlfriend, or perhaps a woman he's seeing. She suggests the go somewhere quiet. This instantly makes us wonder if she's up to something, however later on we discover she becomes victimised.
A red herring comes along as the couple are alone in the car, they shoot at the car before shouting abusive language at them but soon drive off. We wonder if they are going to harm the couple but they don't. Later a blacked out car comes along. It pulls up beside their car, turns is light off and sits there. This adds mystery. We see cuts from the couples faces looking at the car, to the car itself, not much dialogue is included here. The boy suggests getting out before the girl hastily tells him to remain where he is. The car drives off and we think the couple are okay. The boy asks questions about who was in the car, but the girl won't give a certain answer - then we hear a screeching as the car turns around. At this point a haunting feeling dawns upon the viewer, the headlights of the car come towards us. When the car pulls up a man steps out with a bright torch, the torch is shinning brightly on the couples face, giving us one last good look at them, the boy exclaims "you scared us!" right before he is shot, blood splatters over the girls arms right before she is too shot - we see this all in lots of quick cuts building a lot of tension. The man walks away - much like the car he was in drove away - then comes back - again like the car, before shooting the boy again repeatedly as he tries to stand and regain strength inside the car. The going away and coming back element, slightly confuses us and leaves a somewhat distorted feel to the film.