I'm interested to know why the video footage has no audio until almost just before the clearly-heard voice (presumably @TaxiWarrior\'s) starts saying 'Where are you going?'. The very beginning of the sound is a good while after the film starts. This seems like the film has been edited. I wonder what was audible before that, which the filmmaker doesn't want heard?
Just before the monologue of 'Where are you going' and 'call the police' there's a small noise that sounds like the squeak of a slightly poorly aligned brake (which it has to be said means the rider's unlikely to be On Here).