Moon, Edinburgh International Film Festival

Don't be fooled by the generic-sounding title: Moon is one of the most original sci-fi films in years. Better still, it's British and made for the sort of budget – $5m – that wouldn't pay for half a Transformer in Hollywood.

Far more satisfying than Danny Boyle's Sunshine – the last time the British film industry tried to crack the genre – Moon is the first film from Duncan Jones, son of David Bowie. Produced by Sting's wife, Trudie Styler, any thoughts that this might be some music industry vanity project are swiftly banished as its compelling story unfolds.

Helium 3, a real but rare substance used in nuclear fusion research, is being harvested from the Moon, providing 70 per cent of the world's power. Cut to Mining Base Sarang, an isolated unit on the Moon run by a crew of one, Sam Bell (Sam Rockwell). For company he has Gerty, a battered-looking computer, voiced by Kevin Spacey, who keeps the base running smoothly.

Coming towards the end of his three-year contract, Bell is desperate to get home to his wife and child.

"I'm talking to myself on a regular basis," he half-jokes. His only entertainment seems to be watching re-runs of Bewitched and carving a model village out of wood. When Sam sees a hallucination of a girl in the base, it becomes clear he's beginning to endure some sort of meltdown. By the time he sees her again, this time causing him to crash his buggy, it's evident he isn't just suffering from a bad case of cabin fever.

Any further revelations would ruin what is a delicious plot that bears more in common with the themes of Ridley Scott's Blade Runner than, say, Stanley Kubrick's 2001: A Space Odyssey. It deals with perennial sci-fi staples – from alienation to the morality of scientific advancement – in a way that reinvigorates the genre without being po-faced about it.

When the isolated Sam wakes up to the sound of Chesney Hawkes wailing "I Am the One and Only", there's a black humour there that becomes increasingly poignant as the film progresses.

Scripted by first-timer Nathan Parker, and based on a story by Jones himself, what makes Moon so impressive is that it never follows the path you expect. Take Gerty for example: with a little monitor displaying a smiley face that shows different expressions for its state of mind, the obvious comparison is HAL, the rogue computer in 2001. Indeed, Spacey, with that indifferent lilt to his voice, brings to mind Douglas Rain's vocal patterns in Kubrick's film; but Jones and Parker never let Gerty become a HAL clone.

As for Rockwell, this is his Cast Away performance – though he's far more convincing and credible than Tom Hanks' showy turn ever was. Without giving away spoilers, his work also has elements of Nic Cage in Adaptation and Jeremy Irons in Dead Ringers, though Rockwell trumps them all.

If the role is hardly new territory for the actor, he's fully convincing as a man who begins to realise his company has betrayed him. Shot at Shepperton, what Jones and his team achieve is remarkable. It's not that the special effects are anything spectacular (the story doesn't require it), it's just that creating a credible-looking Moon setting for next-to-nothing is an achievement as ambitious as the script itself.