DOCTOR: Even if that was the truth, the fact that you're suggesting it shows there's been no change, no hope, no point. We don't sacrifice people. It's wrong, because it's easy.

MISSY: You know, back in the day, I'd burn an entire city to the ground just to see the pretty shapes the smoke made. I'm sorry your plus one doesn't get a happy ending, but, like it or not, I just saved this world because I want to change.

MISSY [OC]: Your version of good is not absolute. It's vain, arrogant and sentimental. If you're waiting for me to become all that, I'm going to be here for a long time yet.

BILL: No, wait. What about free will? You believe in free will. Your whole thing is. You made me write a three thousand word essay on free will.

DOCTOR: Yes, well, I mean, you had free will, and look at what you did with it. Worse than that, you had history. History was saying to you, look, I've got some examples of fascism here for you to look at. No? Fundamentalism? No? Oh, okay, you carry on. I had to stop you, or at least not stand in the way of someone else who wanted to, because the guns were getting bigger, the stakes were getting higher, and any minute now it was going to be goodnight, Vienna. By the way, you never delivered that essay, anyway.

BILL: Because the world was invaded by zombie Monks!