In the future according to "Elysium," the haves and have-nots live in different worlds -- literally.
The richest 1 percent, who are mostly Caucasian, have abandoned our ruined planet and moved into a luxurious space station orbiting Earth. Below them, a ruined Los Angeles teems with minorities who speak a mixture of English, Spanish and Portuguese and are forced to work in factories to keep the eponymous satellite running smoothly.
But the film's hero -- the ex-convict Max, who has five days to live and must figure out a way to sneak into Elysium to treat his illness -- is played by the all-American Matt Damon.
It's a testament to his talent that he is utterly believable as a downtrodden member of the lower class. And it's not a surprise, either: Along the trajectory of his career, Mr. Damon has never seemed miscast, whether he's playing Liberace's gay lover ("Behind the Candelabra"), a dimwitted corporate whistleblower ("The Informant!") or the globe-trotting super agent of the Jason Bourne films.
Most actors who have that kind of chameleon ability develop it with years of life experience. But Mr. Damon, 43, has been mixing things up from the start.
"I've been lucky that I've been able to play all those different roles and haven't been stuck doing just one thing over and over again, because that would drive me crazy," Mr. Damon said during a recent visit to Miami to promote "Elysium."
"In terms of the ethnicity of the people left behind on Earth, Neill [Blomkamp, director] wanted to suggest that the borders of the entire Western atmosphere were all porous now. There was no point in having borders because there were no resources anywhere.
"So you end up with all these languages spoken and all these different ethnicities. There are a lot of Latinos, but there are a lot of white people, too. More than anything, it was about economic deprivation. There is nothing left on the planet, and we're all trying to scratch out our existence. He wanted to create the feeling that we're all in this soup together."
Like Mr. Blomkamp's debut film, 2009's Oscar-nominated "District 9," an allegory about apartheid, "Elysium" lays out its social commentary early and clearly, then sets out to give the audience a breakneck ride.
The movie's prime objective is to entertain, not preach, so it's only after the end credits have rolled that you start contemplating its exploration of class differences and the importance of universal health care.
"Neill doesn't aspire to make message movies," Mr. Damon says.
"I've thought more about the themes in 'District 9' than I would have if it had been a straight-up movie about Zimbabwe and refugees from South Africa. The aesthetic of science-fiction makes it really interesting and cool, but it's also ripe for meaning and interpretation. You sit and reflect on it. It sits with you longer, I think."
Sharlto Copley, a longtime collaborator and friend of Mr. Blomkamp, played the goofy hero in "District 9" and pulls an about-face as a fearsome government agent in "Elysium." Like Mr. Damon, he believes it is imperative to make movies whose primary mission is simply to put on a great show.
"For me, this type of movie is first and foremost an entertainment," he says. "My character doesn't take himself too seriously. And I'm having as much fun as I can as an actor playing him. The political metaphors just help make this fantastic story feel relevant.
"Everyone thinks there's a hard-hitting moral to the story, but there really isn't. Neill isn't Michael Moore. There were some more ironic things in earlier cuts of the film, but there is only so much of that stuff an audience will tolerate in a popcorn movie. You can just take this as a story about a guy who wants to get up to this cool place in the sky."