becoming Brundlefly
Disease has whipped out most of the human population, leaving massive ghost cities. Those who remain generally have two options. Work for the government, virtual slave labour in exchange for security of living in their walled off and highly secure cities, hardly enough food and water to live and small over crowed housing, or face the world outside the cities where wild life had reclaimed most of the world. It is full of the lawless, rapists and murderers. Of course even if you wanted to, the government wouldn't just let you leave anyway. The outspoken and opponents to the ruling often go missing, end up in labour camps or simply turn up dead. The lucky, and that isn't saying much, go to prison.