Spike Jonze has the first idea for Her ten years ago when he read an article about artificial intelligence.
Jonze is back in the director's chair for Her, a film that follows a growing relationship between a lonely writer and his operating system.
Jonze said: "The very tiniest seed came about 10 years ago when I saw this article online that said you can interact live with an artificial intelligence.
"So I went to the website, and I IM-ed this address, and I was like, 'Hi, how are you?' and I got responses like, 'Great, how are you?' And you can talk to it and tease it - not a him or her, it's just typing - and get a little banter going, getting mocked and so on.
"I got this sort of buzz thinking: this thing's actually keeping up with me."
Jonze teams up with Joaquin Phoenix, while Scarlett Johansson has lent her voice to operating system Samantha.
Her has been surrounded in controversy this week as the Hollywood Foreign Press deemed Johnasson voice performance as ineligible for a Best Actress Golden Globe nod.
Johansson has already picked up a Best Actress gong at the Rome Film Festival.
Her is the first film for Jonze sine documentary Pretty Sweet, and first live action feature since the fantastic Where The Wild Things Are.
Her is released 24th January 2014.
Tagged in Spike Jonze