- 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. My sister and I were the living embodiment of the peace we made. I will give all the lives that I have to protect it. You want to know who I am, Doctor? I am the peace. I am human and Zygon.
- The Doctor: Like a hybrid.
- Clara Oswald: [using his mobile, the Doctor gets Clara's voice mail] Hi, this is Clara Oswald. I'm probably on the tube or in outer space. Leave a message.
- The Doctor: Hello, it's Doctor Disco. I'm in the 21th century, don't know what month. I'm staking out some of the most dangerous creatures imaginable...
- [the Doctor stares at two young girls in a playground]
- The Doctor: ...operating under deep cover, trying not to attract suspicion. Give me a call, Clara. Nightmare scenario - I'm worried.
- The Doctor: [walking into the UNIT command post] At ease! I'm the President of the world. I'm here to rescue people and generally establish happiness all over the place. The Doctor - Doctor Funkenstein.
- Walsh: Yes, we know who you are.
- The Doctor: [points to the question marks on Osgood's lapels] Oh, I see you've accessorized it.
- Osgood: Yes
- The Doctor: The old question marks.
- Osgood: You used to wear question marks.
- The Doctor: Oh I know, yes I did.
- Osgood: They were nice. Why don't you wear them anymore?
- The Doctor: Oh, I do. I've got question mark underpants.
- Osgood: Makes one wonder what the question is.
- The Doctor: Oh, and do you still have the presidential aircraft?
- Clara Oswald: I thought you didn't like being President of the World.
- The Doctor: No, but I like poncing about in a big plane.
- Clara Oswald: Doctor, do you want to be alone with that thing?
- The Doctor: It's a command computer. You operate it by titivating the fronds.
- Clara Oswald: Are you enjoying that?
- The Doctor: I snogged a Zygon once. Old habits.
- Kate: It's a nerve gas. Unravels their DNA. Basically turns them inside out.
- Clara Oswald: Where do you keep it?
- Kate: We don't. It was taken. The formula, the lot.
- Clara Oswald: Who took it?
- Kate: Somebody with a Tardis.
- The Doctor: Are you phoning me with your backside again, or are you really sending me a distress signal?
- The Doctor: Colonel, take it easy. They're trying to unsettle you; they're trying to make you paranoid, panicked.
- Walsh: Any living thing in this world, including my family and friends, could turn into a Zygon and kill me, any second now. It's not paranoia when it's real.
- [last lines]
- The Doctor: The invasion has happened; you're probably surrounded by Zygons. Get to the Tardis. Get yourself safe. And apparently my plane is never going to land, but let's see what we're going to do about that!
- Bonnie: I'm sorry. But Clara's dead; Kate Stewart is dead; the UNIT troops are all dead. Truth or Consequences.
- The Doctor: Clara!