Directed by Ridley Scott. Starring Noomi Rapace, Michael Fassbender, Guy Pearce, Idris Elba, Logan Marshall-Green, Charlize Theron 15A cert, general release, 124 min

Ridley Scott's so-called prequel to Alien is spectacular, well-acted and certainly watchable, but, ultimately, is much ado about not much, writes DONALD CLARKE

YOU’RE HAVING a laugh. Aren’t you? This is what all the fuss has been leading up to. When George Lucas delivered a prequel to Star Wars he, at least, managed to produce something properly awful. Like a stubborn strain of syphilis, The Phantom Menace is the gift that still hasn’t stopped giving.

Ridley Scott’s humdrum variation on themes from Alien is not nearly that memorable. Much of it is even pretty good. Michael Fassbender – like WALL-E sucking up Hello, Dolly! – plays a cyborg who models his posture and timbre on Peter O’Toole in Lawrence of Arabia. Noomi Rapace is nicely eccentric as a scientist struggling with a residual Christian faith. But the overall impression is of a film with no centre, no soul, no focus.

Despite all the chatter over the past few years, many viewers will approach Prometheus still unsure what the blasted thing is about. More than a few will leave the theatre in a similar state. Whereas the first Alien had an irresistible purity – a haunted house in space – Prometheus hobbles together a ragbag of ingredients into a mildly tasty, but crudely formed, sci-fi barmbrack.

Noting that the Spoiler Police are becoming increasingly hysterical, we will step carefully when detailing the plot.

The film begins with a sequence that appears to show an alien flinging himself into a prehistoric river and decaying into DNA. Several million years later, Elizabeth Shaw (Noomi Rapace) and Charlie Holloway (Logan Marshall-Green), scientists and romantic partners, locate a mysterious cave painting that seems to invite humans to a distant constellation. For reasons the scriptwriters choose to keep largely to themselves, the boffins decide that the relevant aliens have – there’s a worrying intelligent- design subtext here – triggered the process of human evolution. They are our “engineers”.

We then cut to the spacecraft Prometheus as it makes its way towards the aliens’ planet. Elizabeth and Charlie share quarters with Fassbender’s polite robot, Charlize Theron’s corporate drone and the usual selection of hard-asses and neurotics.

Hang on a moment. Isn’t this the plot of 2001: A Space Odyssey? What does this have to do with Alien? Well, there are certainly a fair few nods to the earlier film. Something nasty does emerge from a character’s stomach. Theron’s mean space captain, like Ripley, tries to bar a compromised crewmember from entering the ship. We eventually end up on the planet that will later be visited by the Nostromo with such catastrophic results.

Anybody coming to the film in search of HR Giger’s sleek monsters is, however, destined to suffer severe disappointment. What we have, instead, is a meandering story featuring endless half-formed diversions and groan-worthy plot twists. The script is co-written by Damon Lindelof, co-creator of Lost, and Prometheus shares that show’s habit of asking really interesting questions and then delivering really uninteresting answers.

The film also embarrasses itself by unconvincingly faking concern about the relationship between faith and science. Characters mention that such a conflict exists. Elizabeth wears a cross around her neck. But no incident expands or illustrates or even brushes past that interesting topic.

Still, Scott remains a master at co-ordinating talented craftspeople, and Prometheus profits from suave special effects work, a thumping score by Marc Streitenfeld and – though the 3D projection reviewed here was appallingly dark – persuasively cold cinematography from Dariusz Wolski.

Nobody could fault the professionalism on display. And the opening hour offers enough intriguing quandaries to keep even the least patient viewer distracted. Theron, Fassbender and Rapace all find ways of fleshing out their roles.

But Prometheus suffers from a near-terminal inability to decide what story it wants to tell. If somebody asked you what Alien was about, you could deliver a satisfactory answer in 10 seconds. Any attempt to summarise the new picture would require Venn diagrams, whiteboards and an overhead projector.

The open ending suggests that we might get a sequel (that’s to say another prequel). Maybe it will locate the franchise’s hitherto evasive narrative spine. Will anybody still care?