Elysium Matt Damon, Jodie Foster, Sharlto Copley. Directed by Neill Blomkamp. Rated R. Opens Friday.

Stop me if you’ve heard this one before: There’s a gigantic spacecraft hovering above a blighted city of Earth. As a result of this spacecraft’s presence over a number of years, society has been cruelly divided in two, with the dispossessed serving as clear allegorical stand-ins for real-world have-nots. If that scenario sounds familiar, you probably saw District 9, the Oscar-nominated feature debut of South African director Neill Blomkamp, in which aliens from a stalled UFO were treated just like the victims of apartheid. Or, alternatively, you may have seen the trailer for Blomkamp’s new film, Elysium, which recycles the same basic idea, this time from the point of view of the aliens, who are played, collectively, by Matt Damon.

Okay, that’s a snarky way of putting it. The year is 2154, and the only aliens in the gigantic slum that is now Los Angeles are the illegal kind, who constitute the vast majority of Earth’s population. In the role of the United States is Elysium, a massive space station orbiting the planet, on which reside the wealthy elite, who’ve fashioned a gated paradise for themselves in which crime, disease and unhappiness have all been eradicated. All attempts by the 99 percent to infiltrate Elysium have failed, but when factory worker Max (Damon) contracts radiation poisoning and discovers he has just five days to live, he decides he has nothing to lose. Outfitted in a ludicrous exoskeleton, he heads off to kick ass, to the consternation of Elysium’s defense secretary (Jodie Foster), who barks angry orders at him in an undefined accent.

District 9 wasn’t what you’d call subtle, but its mock-historical conceit and disgusting creatures, along with an eccentric lead performance by the unknown Sharlto Copley (who turns up here as a maniacal enforcer with a rocket launcher), gave it plenty of extra-allegorical heft. Elysium, alas, has little to offer apart from its heavy-handed political treatise. Damon has rarely looked so bored—even as Jason Bourne he had more to do than clank around toting massive weaponry—and a late-breaking attempt at pathos involving a little girl with leukemia feels perfunctory. Blomkamp has an original voice, but he’s saying the same thing he did last time. Just a whole lot louder.