Never Let Me Go is a difficult movie to review. The premise itself is not revealed until the end of the first act, and really shouldn’t be spoiled, even if the trailer lays out basically the whole film, and most reviews shamefully discuss plot points you are best to let the film unveil. I have heard it described as science fiction, but I'm not sure. Can a film set in the past be science fiction? Even if as the opening titles point out, it’s an alternate past, where every aspect seems to be much the same bar one. Kathy, Ruth and Tommy – played as young adults by Carey Mulligan, Keira Knightly, and the new Spiderman Andrew Garfield – appear to be wards of the state, living in a fussy English school named Hailsham where value is placed on their artistic ability and physical health. Kathy and Tommy share a connection, but both are too timid as teenagers to act on it, allowing Ruth, with a much stronger personality, to insert herself and dominate them both.

This love triangle forms much of the plot, but Never Let Me Go isn’t really concerned with story. It is handled in an interesting way, but mostly exists in order to give the characters something to do while the audience considers the implications of the movie's key idea. 99 times out of 100 this idea would beget an action movie, and I was willing Never Let Me Go to go there, not because I wanted to see some explosions, but because in choosing not to, in having the characters face their fates as they do, it is a far more difficult story to come to terms with. This is about a love triangle, but it’s also about the cruelty humans are casually capable of, about mortality, the importance and the meaninglessness of any choices that we make, the sameness of all of our fates, and the way we blindly accept them.

Never Let Me Go is an adaptation of Kazuo Ishiguo's amazing novel, which is even better than this very good film. Screenwriter Alex Garland has stripped back a lot of its subtlety in adapting it, occasionally stating its themes verbatim in narration, rather than letting the audience realise them, as in the novel. He has also made some necessary cuts for film, getting to the point more quickly than the book did. Mark Romanek, a music video director maybe best know for Johnny Cash's 'Hurt', and the Robin William’s film One Hour Photo, does nothing wrong, which is all he is required to do with a story, script and cast this good. Knightly is riffing off her established persona, and Mulligan and Garfield prove again, after star turns in An Education and The Social Network respectively, why they will go on to be huge movie stars. I realise this is a frustrating review, but hopefully that frustration might bring you to the film, because it really is very very good.

 Never Let Me Go is out now in most major cinemas. Head here for Sydney screening times.