Emma Watson: You also announced that you're going to collaborate on a theatre production.
J.K. Rowling: Yes that was a really interesting idea that Sonia Friedman came up with. I've been so resistant for a long time about theatre productions. Quite a few people wanted to do a Harry Potter musical. I didn't really see Harry as a musical so we said no to all of that, but Sonia came along with a very thoughtful, very interesting idea. I'm quite excited about that.

Emma: Will Hermione be in it?!
Rowling: Well Emma if you are offering to play Hermione... [both laugh] I tell you what I really want. I want you and Dan and Rupert in really heavy make-up in the background of a scene in Fantastic Beasts, and I'll join you and we'll sit in a bar room having a laugh for an afternoon. Do you not think that would be fantastic?

Emma: That sounds like the most fun I can imagine having!
Rowling: And we can mess around as extras in the background.

And then we can see if anyone can spot us. I personally would like to be in drag, just to make sure no one can spot me at all.

Emma: GENIUS!
Rowling: There are so many things that you could say you have achieved, what is the most meaningful to you? What is your greatest triumph?

Of what I've written, Deathly Hallows was a phenomenally emotional experience and my favourite of the Potter series by a mile. It wasn't just about the writing, it was wrapping up a story that had taken me through seventeen years of my life and had meant as much as any literary creation can mean to any writer. I mean, not just because it transformed my life materially, which of course it did, but that comes a poor fourth or fifth compared to the other things that Harry Potter did for me.

But, I hope that the best is still to come. Nothing will ever top Potter in terms of popularity, I've accepted that, but on my death bed I may look back on one of my least popular books and it may well turn out to be the one I was proudest of, because different things matter to the writer.