Never Let Me Go is a haunting film. In adapting Kazuo Ishiguro's novel, screenwriter Alex Garland has shaped the material into a series of hooks that roll around and dig into people's hearts at different points.

That's what it is aiming for and that is what it achieves. If there was a 'haunting' equivalent to tearjerker, it'd be using it here.

I didn't get picked up until quite late but I doubt that, by the end, too much of the audience had been spared.

The film starts in a boarding school that hides a secret which I think I can safely reveal because the film doesn't keep it for long. All the pupils are clones bred solely to provide organ donations for the general population who now have life expectancies of around 100. The clones, though, don't have much chance of making it beyond 30.

The simple striking genius of the conceit quickly becomes apparent. It is a compressed cradle to grave saga, offering the opportunity to do the death bed climax while the actors still look young and beautiful. No need for all the ageing prosthetics.

This is the fleeting poignancy of existence, taken to the max. (It is also, a potent metaphor for the stem cell debate. You can imagine some fundamentalist pro-life group seeing the film as a propaganda tool.)

The film is a very British take on science fiction, similar to Children Of Men but without all the dazzling tracking shots. Romanek shoots everything in the most muted colours possible. The events are supposed to take place between the mid-70s and the mid-90s but everything looks like an overcast Thursday in an off- season seaside resort in the 1950s. That's England: even our sci-fi ends up as a period piece; Logan's run made by David Lean.

The story follows three of the clones from their early teens to the time for their 'donations'. The love triangle is beautifully played first by three child actors (Isabel Meikle-Small, Charlie Rowe, Ella Purnell) and then by Mulligan, Garfield and Knightley.

They do their bit and, by the end, the film breaks your heart. It does, though, rather glide through its tale. There is a frustration about how little this alternate reality is fleshed out. We never really experience how society has been changed by this development.

Most infuriating of all, it is not explained why the clones never think to rebel or escape. The way in which they meekly acquiesce to their servitude reminds you of that other acclaimed Ishiguro adaptation, The Remains Of The Day.

Never Let Me Go (12A)

Director: Mark Romanek

With: Carey Mulligan, Andrew Garfield, Keira Knightley, Charlotte Rampling and Sally Hawkins

Length: 103 mins

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