[web]https://www.channel4.com/video/traffik/series-1/[/web]
I remember watching this when it was first on (1989) and with it now being free on 4OD (and Virgin on-demand) I'm giving it another go - and it's great. There was a movie version made a few years back, but it doesn't get close to the detail that the 6x1hr episodes go into.
I'm thinking to upload the episodes so that those of you outside the UK can see it too, but it might take a while... failing that, if you can get it where you are then it's definitely worth it.