You go to great pains to get the details right in the film...

I work off of authenticity. I want to get the feeling and tone right. I regard this as almost a fable. It's like Adam and Eve; the Serpent is the Marquis, who presents the apple. This type of drama is re-enacted over and over again. When the people are set free from the asylum, how will they behave once they have the knowledge of good and of evil? That's what the story is about.

Do you think Sade still bears reading?

There are sections of Sade that are witty and philosophical. In many ways, Sade was dealing with not only his own demons but Rousseau, and people like that. He was trying to answer things about how he felt nature played on our souls. Rather than the noble savage, he envisioned something else. He certainly bears reading. For me, you can't read him at a single sitting, because in some ways in his glee, he overdoes it at some times. It can become gruelling.

What do you think of Hollywood these days?

There are a lot of nice people in Hollywood and on occasion they make great movies. If I have any problems, it comes from speaking my piece. I'll say what I want to say, and I'll defend it. I'm a relatively easy-going person; though once I get involved with a project I get pretty obsessed. You can think of nothing but what you're working on. For me a film is a great educational process; for me it's a university unto itself.

Read an interview with one of the stars of " Quills" actor Joaquin Phoenix.