What is the role of the returning bicylist whizzing down ...

What is the role of the returning bicylist whizzing down the pavement in A Week in December?

The bicyclist began as a simple observation. In London, bicyclists think they are immortal. They never observe any of the simple rules of the road. It is as though they think that, rather than being more vulnerable than cars, they are less so; they must believe their self-righteousness renders them impervious to harm.

They are a very characteristic phenomenon of modern-day London.

They also represent...