In a year full of surprise hits without stars, District 9 stands out as an even more unlikely box office champion than the crowd-pleasing comedy The Hangover or the supernatural thriller Paranormal Activity.

The low budget production (it cost an estimated $30 million) with a cast of unknowns directed by another unknown (Neill Blomkamp) bucked conventional Hollywood wisdom by proudly wearing its message on its alien sleeve and slyly combining an apartheid allegory with a good dose of action.

The result? District 9, which boasted the guiding hand of Lord of the Rings' Peter Jackson as producer, cleaned up at the box office, raking in over $200 million globally.

Even more impressively, the film, featuring a non-actor -- South African Sharlto Copley -- in the lead, also became one of best-reviewed releases of the year.

That was the real surprise, the great critical reception we got, Copley, 35, told Reuters. I'd anticipated that people would find all kinds of holes (in the plot) and problems with my performance, but I think critics overlooked a lot of things simply because it's such a fresh film.

District 9 combines familiar commercial elements like aliens and violence with a new setting, some sharp political subtext and a character - Copley's nerdy bureaucrat Wikus -- that is unexpected in a genre piece.

Copley plays a South African official in charge of relocating some 2 million extra-terrestrials from a shanty town in Johannesburg but who ends up being hunted by his own employers.

I made the film for me, which is the only way I think you can make a film as a director, said Johannesburg-born Blomkamp. It's the only yardstick you have, and I thought it would appeal to a small core of diehard sci-fi fans, so all the mainstream critical praise just caught me off guard.

OSCAR CHANCES

So what chance does District 9 have of breaking through at this year's Oscars now that the best picture category has been increased from 5 to 10 nominees?

Everyone is very curious as to how it's going to play out, said Leonard Maltin, film critic for the TV show Entertainment Tonight.

It's one of the best-reviewed films of the year, and for good reason. It's one of the most original films of this, or any, year, and I think it's worthy.

Historically, the Oscars have recognized fantasy and science fiction genre films in every category but the big one, Maltin said. So maybe this is the year.

Blomkamp, 30, said he would be shocked if it got a best picture Oscar nomination but I think Sharlto deserves a (best actor) nomination, though I don't know how realistic that is.

Whatever happens at awards time, Copley and Blomkamp are already being wooed by Hollywood.

My career's changed overnight, admits Copley who's currently shooting The A-Team, a hard-core action version of the campy 1980s TV show that co-stars Liam Neeson and Bradley Cooper.

It was my favorite show as a kid, and now I'm playing Murdock, so it's a dream come true. And it all happened because of District 9. One of the producers saw it and then went after me for the role.

But while Copley is happily meeting directors, studio executives and weighing up 20 new scripts, Blomkamp sounds more reserved.

I'm a bit more of an anomaly. 'District 9's success has allowed me to go back to what I really want to do, which is to be in a powerful creative position where I can't be messed with too much, he said.

But I'm not Peter Jackson or Jim Cameron, so I can't be at that level of creativity with a $200 million budget -- but I can certainly have it with a budget even slightly higher than District 9, and that's my goal.

Blomkamp has already signed on to do his next film - another sci-fi idea which is very much mine, and which I'm busy writing, and which I can keep control over, he adds.

So Hollywood has come knocking, but I'm not opening the door the whole way.