Her

Starring Joaquin Phoenix as Theodore Twombly, "Her" is set in a nearby future. It is an urban, technology-rich environment with which we can readily identify - not some wacky far-off science fiction world. Twombly makes a living by writing personal love letters for people with difficulties expressing their feelings- though ironically his own marriage has crumbled. The film was written and directed by Spike Jonze.

I think we all know what a computer operating system is. Well in Twombly's world, a new kind of intelligent operating system has been devised which is so advanced that the voice of the system attunes itself to its owner. Twombly wear an earpiece and he can for example instruct the voice to read his emails or play him particular pieces of music. He gives this increasingly seductive digital companion a name - Samanatha - who, incidentally, is voiced by the actress Scarlett Johansson.

As you may have already guessed, Twombly begins to fall in love with Samantha. She seems so much a genuine presence that he even takes her on a double date to Catalina Island with an office colleague and his girlfriend. They also wear the requisite earpieces.

Making his way between home and work, it begins to dawn on Twombly that many of his fellow city dwellers are also in intimate relationships with their operating systems and he asks Samantha how many other users she is in love with. She says 641.

At the end of the film, Twombly sits on the roof of his apartment block with the girl from next door - Amy (Amy Adams) who has also had relationship problems with a real man and with her own operating system voice. They look out over a beautiful, electric twinkling cityscape and she rests her head on his shoulder - as if the promise of genuine human love remains beyond the bounds of the film.

Science fiction and fantasy don't readily appeal to me. I normally prefer films that are very much rooted in real human experience - such as "Twelve Years A Slave" or "Long Road to Freedom" but "Her" was genuinely engaging and Joaquin Phoenix played his role with appropriate amounts of understatement and vulnerability. You look around yourself today and you see people who are quite obsessed with their mobile devices - headphones in, smiling inanely, sometimes holding conversations through hidden microphones - like lunatics walking around talking to nobody. It is already becoming a world in which everyday reality is retreating as people embrace the comfort of their virtual sanctuaries. And it seems to me that Spike Jonze has simply stretched that slightly frightening notion a little further - holding up a mirror to give us a partial image of what we might become.