The Doctor: Which one are you? Human or Zygon?
Osgood: I don't answer that question.
The Doctor: Why not?
Osgood: Because there is no question to answer. I don't accept it.

Clara: Oh my God, that's me.
Jac: I think we should wait.
Clara: Look, they're here. They're growing duplicates of us. We have to destroy them. I've seen this happen before. It happened to that little boy. They took his parents and then they took him.
Jac: But I don't see how these are duplicates. That's not how Zygons work. They don't grow duplicates. They kidnap the originals so, these... These are the humans!

I'm sorry, Clara is dead. Kate Stewart is dead. The UNIT troops are all dead. Truth or consequences.

Bonnie

Osgood: Never really met Clara. Pretty strong, yeah?
The Doctor: She was amazing.
Osgood: No, not was... is. It's not from the Zygon. It's from Clara.
The Doctor: How?
Osgood: She's not dead. She's in a pod somewhere.

The Doctor: Let me negotiate peace. You can't commit mass murder...
Kate: Then why did you leave the gas with us?
The Doctor: The boxes are safeguards for both species.

Bonnie: It's empty, isn't it? Both boxes. There's nothing in them, just buttons.
The Doctor: Of course, and you know how you know that? Because you've started to think like me.

You know, I'm over two thousand years old. I'm old enough to be your messiah.

The Doctor

The only way anyone can live in peace, is if they're prepared to forgive.

The Doctor

The Doctor: I need to know. Which one are you?
Osgood 1: I'm Osgood.
The Doctor: Human or Zygon?
Osgood 1: I'll answer that question one day. And do you know when that day will be?
Osgood 2: The day nobody cares about the answer.

Clara: You must have thought I was dead for a while?
The Doctor: Yeah.
Clara: How was that?
The Doctor: Longest month of my life.
Clara: It could only have been 5 minutes.
The Doctor: I'll be the judge of time.

They came to find me. This is my station. My lab. I've pieced together the rescue as best I could.

Rassmussen

Nagata: What are you doing?
The Doctor: I've hacked into your helmet-cams.
Nagata: What?
The Doctor: Reviewing the footage. There's something not right here.
Nagata: We don't have helmet-cams.

Doctor Who Quotes

There's a horror movie named Alien? That's really offensive. No wonder everybody keeps invading you.

The Doctor

The Doctor: It's a risk.
Graham: Oh, like none of our other trips have ever been risky.
The Doctor: I have apologized for the Death Eye Turtle Army! Profusely.