It’s a movie about aliens. In South Africa. And it rocks. At first glance, “District 9” looks like a rather bizarre mockumentary in the style of last year’s “Cloverfield.” However, this story of slum-dwelling extraterrestrials, called Prawns, and their human oppressors is far more compelling than any amount of running and screaming.

The movie opens with documentary-style footage of a colossal spaceship resting above Johannesburg. Character interviews tell how District 9, the temporary holding area for the ship’s inhabitants, was allowed to decline into a massive slum. Twenty years later, in the present day, a project is underway to forcibly evict the Prawns and move them to another location.

In the process of ransacking a Prawn residence for illegal materials, the head of the eviction team, Wikus van de Merwe (newcomer Sharlto Copley), is exposed to alien biotechnology and begins to physically transform into a Prawn, forcing him to seek shelter among the very beings he was working to tyrannize.

The movie is brazen in its examination of human tendencies toward cruelty to the Other in society. Certain scenes in the film reflect not only South African apartheid, but also episodes from the Opium Wars and the events preceding the Trail of Tears. In fact, Wikus openly compares the new settlement being constructed for the Prawns to a “concentration camp.”

The military-industrial complex, symbolized by the mega-corporation Multi-National United (MNU), which oversees District 9, also undergoes a cutting critique. Human and Prawn lives are nonchalantly ignored in the organizations obsessive quest for alien weapons technology.

This very technology represents the film’s biggest stumbling block: the third act, the main scene of which is a three-way battle between MNU mercenaries, Nigerian gangsters, and a Prawn war-robot, is violent to the point of an almost literal bloodbath. But the violence seems purposeful instead of merely gratuitous, representing an explosive release of pent-up human id, as if humans in general would, subconsciously, like nothing better than to exterminate the Other among them.

Gore aside, the special effects in this film can only be described as superb. As CGI creations, the Prawns themselves are rivaled only by the creatures in “Lord of the Rings” and 2005’s “King Kong,” both also Peter Jackson productions.

Director Niell Blomkamp delivers a gritty, incredibly real tour de force story that masterfully breaks out of the conventions of the sci-fi genre. “District 9” is sure to be remembered not only for its tale of perseverance in the face of astronomical odds, but its unique message that one does not have to be human to be dehumanized.