The Day the Earth Stood Still is a movie starring Keanu Reeves as the doom-sayer, the alien in a dark blue suit whose ultimatum is actually a foregone conclusion. The fate of the earth is sealed by a step mother and her child as they huddle under a Central Park pedestrian bridge, waiting for the swarm of silver gnats to disperse.

The film's low-key ending reflects the film's overall charm. Like Independence Day, it is an end-of-world story. But unlike the earlier film, The Day the Earth Stood Still is not tied up in patriotic knots. In fact, the supremacy of the United States is, here, deeply questionable.

Once he's emerged from the placental blubber that had helped him survive the trip to earth from somewhere in deep space, enclosed in a gorgeous designer bowling ball with a surface marked by swirling clouds and patches of light, and accompanied by a 'guardian' of milennial height and super powers, Clotu, played by Reeves, gets to talk with the secretary of defense in the US administration.

Clotu wants to talk with the totality of world representatives assembled at the United Nations. This explains the choice of Manhattan for the arrival. "Do you represent a civilisation?" asks the woman. "I represent several civilisations," replies Clotu. "Are you aware of an imminent attack on the Earth?" "I want to speak to all world leaders." "You can speak to me." "Do you represent all the countries of the planet?" "I represent the President of the United States."

It's a nice moment of irony, a distinctly post-Iraq moment. It reflects today's world of emerging, non-Western powers. Subtle irony replaces bravado and it's a welcome change. Where, in Independence Day, the aliens were rather ugly and supersized - truly alien - in the new film the alien is clad not in fighting trim and mounted in a space ship but is dressed in a plain, blue serge suit.

The story unfolds and, it's soon clear, Clotu is not out to conquer for gain or glory. He's here, rather - and the following will spoil the ending if you haven't already seen the movie - to inform the Earth that they have been selected for extermination in view of their deleterious effect on the environment. "The Earth is one of a very small number of planets that can sustain complex lifeforms," Clotu explains to the astrobiologist (step mom) in vindication of the decision to wipe out humanity.

Animals love the glowing spheres that have descended at different locations throughout the globe, collecting specimens. Madam secretary is perspicacious enough to recognise that the purpose of the spheres is to be an ark for all terrestrial life.

Another nice touch is the fact that events unfold in public, whereas in so many sci-fi flics with similar scenarios the government (usually the US government) is able to keep it all a secret for years, until the catasrophe. Here, images are grainy because "taken from the Internet" and show how people around the world react to the sphere come among them.

John Cleese, as a Nobel Prize winner, executes a pivotal role nicely. His elegant home, with paintings on the walls, low-slung and minimal furniture, and Bach playing on the stereo, is pure elite kitsch. Nevertheless, Cleese pulls off the cameo really well, providing the justification for Clotu's decision to finally spare the human race: people only change when they are at a crisis, and never before.

Visually, the movie is also quite restrained. The highly engineered robot that accompanies Clotu is made of an attractive silvery material, and it has one shining beam of a red eye that tracks from side to side within a Ned Kelly like opening where its face should be.

The method of destruction - which actually starts near the end of the film - is ingenious, involving tiny, replicating insects that are what the robot is actually constructed out of. The observing men try to 'flash' the robot to cinders, as he stands captive in a specially designed underground bunker for alien observation. But he remains unscathed.

Lifting his grey hands, palms inward, the robot's fingers begin to shred and powder, then swirl in a grey cloud. Slight tracks, as though an insect were eating away at it, appear in the glass of the observation dock. Panic sets in amoung the men observing the robot and the cloud of grey gnats cracks through the glass, explodes out of the fortress-like bunker and then proceeds to eliminate the manufactures of mankind.

The swarm is massive and goes in all directions. Like the Internet, there is nothing to attack, nothing to hit. It is ubiquitous, and cannot easily be contained.