Last week I saw a movie that made me want to change the world. And it was about aliens from outer space.

When I rented District 9, I certainly wasn’t expecting to have my heart wrenched around. I was in the mood for fun summer science fiction—a gripping adventure lightly spiced with the mystery of the unknown and some cool special effects. The fact that Christianity Today put it on its “Top Ten Redemptive Films” seemed a convenient way to persuade my parents that it was all right to watch a movie that was rated R, and not much else. I settled down with my metaphorical bag of popcorn and prepared for a rousing good time.

That’s not what I got at all. The central conceit of District 9 is that aliens have landed just outside Johannesburg, South Africa—but not the kind of aliens who want to either conquer the world or bring lasting peace and prosperity. Instead, they are scaly, repulsive-looking humanoids, intelligent enough to talk, barter, and build but not intelligent enough to find a way past human fear. Disputes come up between the aliens and the humans; violence breaks out; finally, the aliens are contained in a temporary camp just outside the city, which quickly turns into a slum. They live in squalid huts, do most of their human business with violent gangs, and get by scavenging or selling their weapons—so far inoperable by any but themselves—on the black market. The government doesn’t step in, except to control their population by destroying their incubating eggs or to guard the boundaries of the barbed-wire-lined camp. And then, twenty years after the aliens landed, the protests of the citizens of Johannesburg grow too loud for the government to ignore, and it is decided that the aliens should be moved to another camp further away from the city. All that needs to be done to protect the dubious legality of this operation is to force every alien to sign that he will give up his home to move to this new land. And if they won’t sign? Well, who will miss a dead alien?

The chilling thing about this film is that, despite the hideous aliens, arcane weapons, and unbelievable pieces of technology, this story is not far-fetched at all. Watching it, I realized that all of the callous disregard for life, all of the casual violence, all of the flinty calculation of how much money outweighs a death actually happens. Humans treated other humans like this in apartheid South Africa, in Nazi Germany, in the United States in the reservations, without even the flimsy excuse of pincer hands and scaly skin to magnify the differences between intelligent being and intelligent being. I needed to see this movie, because it is so easy to wrap myself up in the warm, comfortable bubble of middle-class American life and forget that my willing blindness helps horrific actions like this survive throughout the world.

I must warn you, the violence was almost more than I could stomach. This film is not for the faint of heart. And yet, I think that the violence—and the graphicness of the violence—was profoundly necessary for the movie to work. I so often blithely watch a film with spectacular explosions, bad guys being dispatched in dozens of inventive ways, and noncombatants being picked off left and right—and am utterly unmoved. It simply isn’t in the best interest of the makers of fun action-adventure films to let violence shake us too deeply, because then we would be reminded of the reality of death and the destructive pyrotechnics wouldn’t seem so fun anymore. The makers of District 9 had no such qualms. Violence is there, in abundance, but none of it is the kind of fighting that makes you whisper “that’s so cool!” under your breath in the movie theater. It is gritty, and disgusting, and real—and after seeing it, instead of wanting to take martial arts lessons, you want to fund an organization to rescue child soldiers.

If District 9 had been all about human sin and human atrocities, it would still have been worthwhile to watch, I think, because we so desperately need to be reminded that the world is yearning for God, waiting for God to come rescue it with bated breath. Sin is real, and it has consequences that should turn our stomachs—far better to be nauseated than to accept violence with complacency. However, District 9 doesn’t stop with just exposing injustice and cruelty. There is unexpected heroism, as well—unexpected not because it comes from the inexperienced or the weak, as in so many stories, but because it comes from the cruel and the willfully ignorant. The hero does not emerge from the young hero-in-training, but from the antihero. And this, perhaps, is the best reason to watch District 9. Is it not true that we are often the antiheroes of our own stories? Our petty selfishness and our little cruelties tear up the world around us, and most of the time we don’t even notice the bleeding wounds we have created. But this isn’t the end. God works, not simply to contain our damage, but to turn us into heroes. He not only disarms us, he gives us his own sword of the Spirit, and makes us his champions to fight the good fight. He transforms us from mockers of his Word into his messengers. It is this that can give us hope in our darkest moments, when it seems that everything we touch turns to ash. Like the characters of District 9, we do not start with a clean slate—but like those characters, we can change.