So the Singularity happened. All because a guy lost his arm.

Who's the main character and what is his clear obtainable goal?

Cool. Don't forget that if this is a film, you need to visually represent the antagonist somehow. Were you thinking along the lines of a robot, cyborg, or something like "Hal-9000"?. Or an "imaginary human form" like the Oracle lady in the Matrix. A clever way of doing this was in the movie "Moon" Starring Sam Rockwell.

If the AI is just a bunch of computer code, then I suppose this could work too. Remember Jurassic Park?

(Off topic, some say the inspiration for the Radiohead album Kid-A is the concept of the first artificial human).

Anyway, I'm fascinated.

Thanks for that - I appreciate it. There is an antagonist, and it's not the initial AI or society (& not nanobots :) ), but one of the offspring of the first AI. It's about how the internal society of artificial intelligences (intelligentsia?)begins to work, form and self regulate, and does so before it's really noticed by the outside world. The rogue AI is a serial killer of sorts, but killing of the other personalities, the other AIs. This is about the why of that and the repercussions both within the networks and on the outside of them.