Neill Blomkamp's telling of District 9 is done almost entirely through the lens of (mock) documentary and news cameras. While this is far from new, it does keep the story moving quite nicely and gives the events a touch of reality (for example, news crews covering a "terrorist attack" in Johannesburg).

Another strong point of the movie is its characterization, both human and alien. Wikus van der Merwe starts out as a bumbling and simple-minded bureaucrat, who soon becomes the most wanted man in the world (and certainly South Africa). Sharlto Copley does an admirable job in his first professional feature film, capturing van der Merwe's fear, anger, paranoia and his lingering humanity. The rest of the characters make up the numbers; David James plays Venter, the colorless mercenary sent to hunt van der Merwe down; Louis Minnaar is Piet Smit, the scheming and two-faced director of the alien-relocation organization, and also Wikus' father-in-law. Eugene Khumbanyiwa turns in a great performance as the wheelchair-bound (and unfathomably dangerous) Obesandjo, a Nigerian warlord. Jason Cope plays "Christopher Johnson", the primary alien protagonist and our audience surrogate for the unwelcome visitors.

The aliens - derogatorily referred to as "prawns" - add another element to the movie. We never learn anything about their culture, their origin, or their planet. We don't even know what they call themselves, or what their own names are. While that's standard fare for the usual "invading alien" movies (Independence Day, The War of the Worlds), what makes it more interesting here is that the aliens are victims, sympathetic characters. They never intended to be stranded on Earth, and all they want to do is go home. Instead, they're condemned to live in slums, reviled by their rescuers, and are constantly monitored by paramilitary troops. Little touches, like a statue outside District 9 of a human and an alien holding hands, lend authenticity to the idea of a social experiment, and a genuinely well-intentioned gesture of help, gone wrong.

It would have been the easiest thing in the world to have turned District 9 into a morality tale about any ethnic group that's ever been persecuted (take your pick) - but Blomkamp makes the aliens interesting enough that it doesn't require a huge leap of imagination to think that something like this could actually happen. It's so well done that it's much easier to imagine than you'd think.

The movie does lag a bit in the final act, which turns into a basic bullet festival. Fortunately, it doesn't last too long, and given the progress and evolution of the story, makes sense in its context and is entertaining in its own right. In other words, it's not gratuitous. The CGI of the alien mothership and the aliens themselves is brilliantly done, and serves to add to the gritty realism of District 9. The special effects and science fiction elements are done in moderation and rarely (if ever) over-the-top, meaning this movie will appeal to those who might otherwise eschew anything with spaceships and aliens as part of its story.

Blomkamp and Copley present District 9 as much more than a standard science fiction/alien movie. This is a very deep, well-told and well-created story that bears repeated watching (strong stomachs might be helpful) and much, much afterthought.