District 9 is a peculiar beast. It’s a tale where the impact of first contact with an alien race is about our effect on them, rather than [usual] other way around. While it could have been an effective film were it made anywhere else, it would not achieve the resonance it gains from being set in [and above] Johannesburg, South Africa.
It’s been twenty years since the alien mothership glided to a halt above the city and its crew and passengers were taken from it and placed in District 9. The intervening years have not been kind to them and now the giant conglomerate, MNU, is about to move them from their district – which is in effect a ghetto – to District 10, which is more of a concentration camp.