I had virtually nothing to do in number four. In fact, when there's nothing to do like that, and they say, 'Do you want to come in for a couple of weeks?' you go, 'Well, I'm busy. Oh, God. All right.' Because the thought that somebody else might wear my wig is just too painful. But I have a little bit more to do in this.

I get to have a wand battle with Gary Oldman, possibly my favorite actor in the universe. We get to play around like two 10-year-olds - and with kind of unlimited sci-fi imagination. It's fun. We just go, 'Well, how about if I ... .' And anything you finish that sentence with, they go, 'Yeah, OK. You can do that.' So it was magnificent.

I fell to my knees and begged. It didn't do any good. I'm sure she doesn't need plot ideas from me. But I made my point. We'll see. Like everybody else, I'm holding my breath to July to see what's in there. I just want to bust out of prison, that's all. I don't want to stay in Azkaban most of my life.