Brilliantly realised, complex and humane, Minority Report is easily on a par with Blade Runner as one of the best adaptations of Philip K Dick's work ever made. There hasn't been a science fiction film this good for 20 years. Forget shiny buildings and action-packed chases - Minority Report has both, but it has so much more, elevating it far above the status of popular pulp.

Spielberg has taken Dick's short story and spun it out into a powerful plot which retains the labyrinthine twists of the original and adds a few more, comfortably filling two and a half hours. Here we see a world as detailed and paranoid as the original, yet warmer, more human and very close to home; this only serves to make events as they unfold more chilling. It's certainly timely, but the things which it has to say will probably always be relevant. This isn't science fiction as escapism; it's science fiction as a political tool, as a means of making statements about the human condition. It's science fiction film-making at its very best.

This isn't to say that Minority Report is a perfect movie; like any work on such a grand scale, it has its flaws. Sometimes Spielberg's habitual sentimentality creeps in just a little too far, yet this serves well as a counterpoint to the more vicious angles of the plot. Visually it is stunning, often reminiscent of Kubrick. Flashy future technology and architecture have been cleverly interwoven with the familiar, even the old-fashioned, to create a world which we can believe is not too far away from our own; a world which has changed, but not unrecognisably.

This is a world where, in the District of Columbia, murder has been done away with thanks to the use of precognitive individuals who can spot crimes before they happen, giving the authorities a chance to intervene. All sorts of questions are raised hereby, to do with free will and whether or not one can be guilty of a crime one never actually committed, but Spielberg has the sense not to linger on them for long, since there are other matters of equal importance to be explored.

Perhaps his greatest triumph is that he draws strong performances from all of his actors. A superb script enables several formidable, rounded characters to emerge, by contrast with Dick's own spare characterisation. Tom Cruise is perfect in the central role, eschewing the glamour which many feared might ruin his performance. This is perhaps the best work of his career to date, rivaling Eyes Wide Shut. The supporting cast are all excellent, which is vital to the process of misleading the audience as to just whom one can or can't actually trust.

Some of the audience with whom I saw this movie evidently came away disappointed; they'd been expecting trademark Cruise glamour, Spielberg cutesiness and a pulp action plot. What they had been forced to endure instead was something which demanded that they use their brains. Minority Report is not a film for the lazy, nor for those who want to go away afterwards with the cheerful feeling that everything is alright. It is dark and challenging, and very good at getting under one's skin. Like all great art, it will offend. But give it a chance, and it'll give you a great deal in return. It may be many more long years before we see its like again.