[Princess Margaret] was loud, an extrovert, an exhibitionist, loved fashion, loved color, loved music, loved drama, loved the theater, wanted to be a ballerina or actress, was always the little one putting on the school plays, and [princess] Elizabeth reluctantly did it and got stage fright.

It's this amazing combination to play, really, of somebody who's actually very fragile and hasn't really grown up properly yet - at least in a healthy environment - and has suffered immense loss with her dad - like that line where she says, [in the words of her father [King George VI], "Yes, 'Elizabeth is my pride but Margaret's my joy." She holds onto it!

That external struggle mirrors the struggle of this life force of energy that [princess Margaret] was.

My dad is a big extrovert - he's a doctor - but he always loved [William] Shakespeare and he took us to tons of theater.

It was always said you couldn't have two sisters less alike. In a way [princess] Elizabeth was always internalizing everything and [princess] Margaret was always externalizing everything, so that became the basis. The storyline becomes about these two sisters: they're fighting for their position or trying to establish their identity in the world alongside each other and in relation to this establishment which only those two were a part of.

I did a lot before [being cast] because I knew how important it would be for playing somebody real, or attempting to - to show the team [the role] was something I would be fascinated to do. I read a couple of biographies and I watched everything I could find [about princess Margaret].

I watched her do speeches, but the only footage we could find of [princess] Margaret was archive footage, which was of her public presentation of herself.