Domhnall Gleeson plays Caleb Smith, a programmer who's just won a contest to go spend a week with the reclusive founder of the very successful company Caleb works for. Oscar Isaac plays the manipulative and extremely intelligent company founder Nathan Bateman. Their initial encounters are uncomfortable, even creepy. They're isolated a long way from anywhere on Nathan's huge estate, the only other person a Japanese woman who speaks no English at all - "so I can talk trade secrets around her and not worry." But there's one more ... person. There's Ava (Alicia Vikander), the artificial intelligence in a human-like body on the other side of a pane of glass that Caleb finds out he's here to test.
The movie moves slowly and there's almost no action, but this is a movie to give your full attention to: the writing is fantastic and brain-twisting ideas about intelligence and behaviour come thick and fast. This is the polar opposite of Million Dollar Arm which I watched yesterday: while charming, that one required no thought whatsoever and in fact actively encouraged you to believe their views on how people should behave and change. This one wants you to think. It seems they've decided that AI isn't a very good thing, but the movie encourages you to reach your own conclusions. This is what Science Fiction should be: superbly done and incredibly thought-provoking.