What's your response to people — like me! — who were disappointed that AD wasn't a character we already knew or had met before, like Spencer's sister Melissa?

"Well, the character wasn’t exactly unknown! We met the character several times over the past ten episodes, which was the wink. But it really would be impossible to make all of the viewers happy. Some people wanted it to be one of the girls, which, to me, made no sense whatsoever. Why would they torture themselves in that way? As the writers, we thought with it being Spencer's twin, you got the best of both worlds. It was almost like having it be a Pretty Little Liar, but one step removed, because at times you forget that you’re watching Alex instead of Spencer. So for me, it was getting to have your cake and eat it too."