I approach every part I'm asked to do and decide to do from exactly the same angle: who is this person, what does he want, how does he attempt to get it, and what happens to him when he doesn't get it, or if he does?
I have a photograph at home of Fred Astaire from the knees down with his feet crossed. It's kind of inspiring because it reminds me his feet were bleeding at the end of rehearsals. Yet when you watch him, all you see is freedom. It's a reminder of what the job is about in general, not just being in musicals.
I never talk about 'Harry Potter' because I think that would rob children of something that's private to them. I think too many things get explained, so I hate talking about it.
One thing I will say - my job gets harder and harder. The more you understand about what you are capable of, the less the instrument can do it physically. It's an inverse equation, if that's the right phrase. I just slammed those two words together. It sounded right.