Theodore is leading a hum-drum, isolated existence in a near-future LA when the new operating system 'os1' is released. The newly developed 'Artificial Intuition' provides Theodore with a new companion who proves to be more human than even her creators expected. 'Samantha' is a construct that quickly turns from digital slave to friend to lover. In shorthand, it's a movie about a guy who falls in love with an advanced Siri.

The synopsis leads you down a path of expectation that is entirely inaccurate. Her pleasingly surprises you at several turns. Theodore isn't the socially recluse hero you expect him to be (like that of Lars and The Real Girl which tackles some similar themes). Rather, Theodore is relatable, likeable and at a time in his life where you can completely believe his attraction to Samantha. Samantha isn't just a human voice, either. If watching and listening closely, you understand how she moves and learns throughout the film. She's an entirely believable artificial intelligence system. Her arc is, for want of a better phrase, 'accurate' given the concept of who she is - a machine. In fact the whole film, which would strictly speaking be termed a 'sci-fi' is shrouded in a veil of realism. 

There are several keys to this massive achievement. The first is the design. The costumes and world that Her inhabits is strikingly familiar, yet just out of reach. Yes, this is a world that could easily exist in ten to twenty years. Spike Jonze, the director, is smart enough never to hi-light this. Cheaper, more block-buster directors would spend long aching crane shots taking us through the futuristic LA, or pull out on wide landscapes of the city. We never get this, and the film is better off for it. The characters don't see their surroundings as remarkable, so neither do we. Simple as that. Our future is made real.

The cast is small, but Joaquin Phoenix does a predictably brilliant job. I simply can't imagine who else you would cast in the role. Amy Adams also continues to prove herself as an incredibly astute actress. Scarlett Johanson, the voice of Samantha, is amazing, and incredibly well-conceived by Jonze. 

The film lingers a little in the second act. Theodore's relationship with Samantha goes through two separate crisis points, making the plot feel stretched just twenty minutes too tight. Jonze knows how to write a brilliant scene, and his dialogue is wonderfully naturalistic, but the overall structure of the movie suffered for the point he was trying to make.

Her is not the film you expect it to be. After it, you'll never look at Siri the same again.