There is no filmmaker working today quite like Spike Jonze. He’s the master of thoughtful, playfully reality-bending cinema with punchy messages.

HER tells the story of Theodore Twombly (Joaquin Phoenix), a writer who’s life is persistently haunted by a disastrous breakup with his wife Catherine (Rooney Mara). Theodore loses all drive in his life, along with his ability to maintain any kind of stable relationship. He just works, plays video games and gets his lustful fix from pornography and phone sex, much to the despair of his best friend Amy (Amy Adams). Everything changes when he purchases an intelligent operating system with a vivid and lifelike personality, calling herself Samantha (Scarlett Johansson). Theo and Samantha become fast friends, eventually beginning an unavoidably unconventional romantic relationship.

Joaquin Phoenix turns in an affecting, believable and surely difficult performance. He’s in every scene and practically speaking, talking to himself (to Samantha in the film). Though she was cast late in the day, no-one else could possibly match the husky, cheeky expressiveness of Scarlett Johansson’s voice, and she gives real personality to her amalgamation of Siri and Cleverbot. You can completely understand Theo falling for her, and Samantha for him. Amy Adams is a great supporting player, her character is funny, intelligent and subtly vulnerable, as well as being unrecognisably dressed-down in the same way Cameron Diaz was in BEING JOHN MALKOVICH. Rooney Mara’s Catherine is a life-destroying mythical figure to begin with, only glimpsed in Theo’s painful flashbacks, before she turns up in person to finalise their divorce, and when she does Mara makes a big impact in a short space of time.

The first half of Her is chiefly focusses on Samantha learning how to be human. Except for their inability to touch (articulated explicitly in a disturbing scene where Samantha hires a flesh-and-blood sexual surrogate for Theo) their relationship ends up being just as normal as any other – they laugh, they cry, the joke, they argue, they go to the beach. The second half holds up a mirror and has Theo try (and fail) to understand the complexities of how an A.I. “thinks”, building to a gut-punch of a dramatic twist.

Jonze at first appears highly critical of mankind’s increased reliance on technology, filling the screen with crowds in their own little media worlds, seemingly talking to themselves and actively avoiding any real contact with another person. Jonze’s attitude to the subject matter changes as the film progresses, to the extent that we are asked in the subtext “who are we to judge what is normal?” We’re completely on Theo’s side and feel for him when his ex-wife berates him for being “madly in love with his laptop”. He gets something out of his relationship with Samantha, he can be himself and open up in a way he hasn’t been able to with a real person since Catherine. He takes Samantha on a double-date with a work colleague (Chris Pratt) and it hardly matters that one of the four personalities is contained within a handheld electronic device – it just seems like a normal social situation. On the same note, we are asked what “real” is, in terms of his relationship and the age-old science fiction concept of whether a machine can have a soul, or genuine emotions, a thought that ultimately causes friction for Theo and Samantha in a pair of emotionally volatile scenes towards the end of the film.

While he eventually comes down on the side of “do what you like as long as you’re happy”, Jonze uses technology as satire to great comedic effect in the film’s first act. The near-future technology consisting of giant i-Pads, instantaneous voice activated e-mail and internet and projected video games probably isn’t far off from the truth of where we’re heading, and all are strikingly designed. Also rather tellingly, Jonze imagines a future where every task in our lives can be fulfilled on demand with minimal personal effort. Theo’s job involves composing love letters for others, putting himself in their place to express emotions they cannot (or can’t be bothered to). Through this profoundly odd service he offers, Theo can express some of his personality through others, but is still too insecure to show all of himself to those he becomes fond of. That is the ultimate tragedy of his character, that he can only pretend to open up, until he meets Samantha. When he’s not talking to his OS, he only seems even remotely comfortable in his (strictly non-romantic) relationship with his friend Amy, but even then would prefer to talk about her life than his. A blind date with a woman (Olivia Wilde) goes swimmingly well until she asks for a minor commitment from him, and the promise of sharing more, which scares Theo away.

The film moves along nicely, taking time to build the central relationship layer-by-layer, and I was overjoyed that I couldn’t guess where the story was heading most of the time. I’ll just say there are surprises aplenty along the way that will have an impact on your heart, your mind, and your soul, and leave it at that.

It’s exhilarating to have a film that is so satisfying on both an intellectual and emotional level. It would be very easy for a man-machine love story to come off as cold and detached, but Jonze never forgets the importance of the central human relationship. He discusses big sci-fi ideas, but that’s not what the film is ultimately about. It’s about a man and the difficulty he has in opening up to others, and as a shy man myself, that speaks to me on a profound level. Her is uplifting, hilarious, brainy and moving, the perfect sci-fi/romance hybrid that offers us a vision of the not-very-distant future that, depending on your perspective on life, could be hopeful or hopeless. Sorry, GRAVITY, but I have a new favourite film of 2013. SSP