His first film, District 9, was an unexpected success. He was a young director from South Africa who got to make basically his dream film. It was about aliens who arrive on planet earth, on the brink of starvation and death. The human response is to wall the aliens off in government-created ghettos. The movie was a thinly-veiled commentary on Apartheid in the director's home country, which was the world he grew up in.
Elysium is, at a very basic level, about the horrifying gap between the rich and the poor. The movie is set in the year 2154. The earth has become so polluted, diseased, and over-populated that the super-wealthy have actually left the planet to live in a high-tech space-station habitat called Elysium. On Elysium, everyone has access to state of the art health care and every need is taken care of. There is an elaborate "homeland security" in place to keep "undocumented" ships from sneaking into this fortress of affluence. The vast majority of humans lived on a ruined earth, where the very air is poisoned. People live short, desperate lives.
The hero of the movie is a man named Max (played by Matt Damon). He's a former car thief/parolee who works for Armadyne, the corporation who manufactures the robot drones who police both the Earth and Elysium. After an industrial accident, Max is exposed to radiation and learns that he has only five days to live. His response is a desperate attempt to get to Elysium to save his life. The arc of Max's character is beautifully moving. He begins as a man interested in self-preservation and ends up becoming something much more.
I don't want to give too much away, because the movie is worth seeing for yourself. One of my favorite scenes in the film is where a child tells Matt Damon a story about a meer cat. The meer cat is on the verge of death because he is so small and other, larger, more powerful animals have hoarded the resources. The meer cat befriends a hippo who helps him get the food from trees he cannot reach on his own. Max asks the little girl, "What's in it for the hippo?"
Max's last words of the film are, "Now I understand why the hippo did it." I won't explain how or why but Max learns the Christ-like lesson of selflessness, and becomes the kind of hero our current, real world desperately needs.