PJ produced it. The director is Neill Blomkamp, and this is his first full length film. He gained a lot of attention (including PJ's) with some short films, and PJ was going to have him direct his film of the videogame Halo. Fortunately (in retrospect), that project fell through and he and PJ did this one instead. The budget was only $30M.
The film begins in a faux documentary style, recounting the arrival of an alien vessel over Johannesburg, South Africa. The aliens are stranded, in poor health and low on supplies. A multinational organization is put together to deal with the extraterrestrial refugees, who end up in a camp (a slum basically), the titular District 9. Tensions rise between the "prawns", as they are derisively nicknamed, and the locals, until a new camp is built far from the city and a civilian contractor is hired to forcibly evacuate the prawns to District 10.
This is about 15-20 minutes into the film, at which point it begins to intercut between the documentary style and a more traditional style. The transitions are seamless in the moment, but very effective in making the whole film seem real, like a piece of history. But that's not the important thing about this film. What's important is how the story unfolds from here on out. I called it "profoundly disturbing" earlier, and it is. It grabs your attention and yanks you right out of your comfort zone, making you think and feel things that you probably didn't want to think and feel. But you probably should anyway. Even now, after a good night's sleep , I still can't put words to it very well.
But I'll try.
D9 isn't just a great sci-fi film. It's a great film. But the sci-fi part is important. because what sci-fi is supposed to do is show a world that almost, but not quite, reflects our own. See, we know what we think about our present reality. We carry preconceived ideas and assumptions (schemas, to be geeky about it) that color our judgement. So when someone show us a reality like our own, we judge it based on what we already know (or think we know). But sci-fi allows the storyteller to show us a reality that is different enough from our own that our prejudices don't quite fit, but still be close enough to show us something about ourselves. D9 is hands down the best example I personally can think of for a film doing this. Just be forewarned, what it shows us about ourselves isn't very pretty. The humans really aren't the good guys here. And the thing is, no reasonably informed person can look at how the characters behave and tell themselves that people just wouldn't do that. Because people have done that. They've done exactly that. To other people, no less. You seriously think that we, as species, would treat a bunch of giant bugs from outer space better than we've treated other people? Not likely.
And yet somehow this little film manages to not be preachy or heavy-handed. Yes, it's violent, even gory. But none of it is gratuitous. The camera, like the story, never blinks, never flinches, never yields an inch. It simply shows us a very real possibility, I think the probability, of how we would act under these hypothetical circumstances. And as much as I'd like to believe Blomkamp is wrong, I can't quite make myself believe that. History just doesn't bear it out.