If I had multiple lives, I'd like to do many things, including being a homicide investigator. I'm not brave enough to chase people and draw down on them. Having spent time with that, it can be an incredibly terrifying job.

I've always been kind of drawn to the extremities of human nature. I wrote my first screenplay when I was 16. The initial idea was a friendship between two prostitutes, and I spent time with a vice squad guy in Cincinnati who brought me to a brothel and gave me the rundown on how street prostitution works.

I think it is the hardest thing in the world. I'm endlessly intrigued by what human nature is capable of, both the horrible things we are capable of and also the heroic things. I'm really interested in exploring that side of human nature.

And as cynical and jaded as many have become, you see the heroic nature of cops, who put aside a lot of their own personal concerns and their families to speak for the dead, which is a sacred thing. Over time there is this thing in them that is very powerful and interesting and provocative to me.

It was a very, very intense and long casting process [for The Killing] because we really had to find the right people who could carry the weight of this story, who had the chops and who had the spirit, where they could bring in so much of their own selves to these characters. So, the casting process took many months.

If I had multiple lives, I'd like to do many things, including being a homicide investigator. I'm not brave enough to chase people and draw down on them. Having spent time with that, it can be an incredibly terrifying job.

Before I write anything, before I create any assumption in my mind about what it's like to be in that world, I go out there first. I'm very drawn to darkness and light, very drawn to cop drama, because there are very few places besides war and murder and a homicide investigation where you see the extremes of human nature - the darkest crevices and cracks in what people do to one another.