As we all know, it is the proper duty of every British subject to come to the aid of the TARDIS. - Steven Moffat

We've kind of got to tell a lie. We'll go back into history and there will be black people where, historically, there wouldn't have been, and we won't dwell on that. We'll say, 'To hell with it, this is the imaginary, better version of the world. By believing in it, we'll summon it forth'.

I think people have come to think a plot hole is something which isn’t explained on screen. A plot hole is actually something that can’t be explained.

Do you know how you make someone into a Dalek? Subtract Love, add Anger.