[The Joker is a] psychopathic, mass murdering, schizophrenic clown with zero empathy. … Last week I probably slept an average of two hours a night. I… - Heath Ledger

I'm not good at future planning. I don't plan at all. I don't know what I'm doing tomorrow. I don't have a day planner and I don't have a diary. I completely live in the now, not in the past, not in the future.

Having a child changes every aspect of your life — for the better, of course. The sacrifices are large, but what you get in return is even bigger than the sacrifices you make. I feel, in a sense, ready to die because you are living on in your child. Not literally, not ready to die — but you know, that sort of feeling in a profound way.

I sat around in a hotel room in London for about a month, locked myself away, formed a little diary and experimented with voices — it was important to try to find a somewhat iconic voice and laugh. I ended up landing more in the realm of a psychopath — someone with very little to no conscience towards his acts … just an absolute sociopath, a cold-blooded, mass-murdering clown .... [being given] free rein [by director Christopher Nolan was] fun, because there are no real boundaries to what The Joker would say or do. Nothing intimidates him, and everything is a big joke."