Arriving without much fanfare but a cunning viral advertising campaign, District 9 is certainly one of the lowest key Summer blockbusters, but has more than made up for that with critical plaudits, audience raves and healthy box office.

We must hope the reason is that amid all the shallow bombast and glittery spectacle that has been the hallmark of the Summer's releases, District 9 actually has some intelligence behind it and expects some in front of it, too. But the beauty of it is the film works on several levels.

Talk about picking off a painful scab, this is a South African film taking an allegorical look at apartheid. Yet, this is no preachy let's all sit down and sing Kumbaya message - the situation is complicated. There are probably PhDs to be had from investigating the politics of this feature, not to mention psychoanalysing audience reaction.

Sharlto Copley plays Wikus, and it takes us a while to realise he will be the focus of the film, we don't recognise the actor and from his opening scenes he is clearly a plonker, and another joy here is that we go along with his journey.

A standing ovation is due to WETA's special effects team, the CGI bits `n' bobs that populate the film all have mass and look like they were on the film set - which helps sell the piece of course.

I have some carps - the plot development that serves as Wikus' wake-up call doesn't really make sense and one of the aliens is a bit too cute. But that's it. The sense of humour that pervades the project is very Paul Verhoeven but without becoming as comic book as that worthy's oeuvre, but it does mean that the film is gross - from cat-food munching to human beings suddenly becoming purée - and the makers can count themselves lucky to have escaped with only a 15 certificate. A collection of loose ends (and loose beginnings, come to that) will ensure welcome sequels.

Particularly enjoyable as the summer movie season competition has been fairly rotten this year. This one deserves the accolades and will find resonance with anyone who opposes man's inhumanity to. well anyone or anything really.