- The Doctor: Immortality isn't living forever. That's not what it feels like. Immortality is everybody else dying.
- The Doctor: People talk about premonition as if it's something strange. It's not. It's just remembering in the wrong direction.
- Clara Oswald: How's it coming?
- The Doctor: Reversing the polarity of the neutron flow. I bet that means something, sounds great.
- Clara Oswald: Okay, it's official. Silence is even worse in a Scottish accent. Are you going to tell me what you're brooding about?
- Ashildr: I've always been different. All my life I've known that. The girls all thought I was a boy. The boys all said I was just a girl. My head is always full of stories. I know I'm strange. Everyone knows I'm strange. But here I'm loved. You tell me to run, to save my life. I tell you that leaving this place would be death itself.
- [Heidi wakes up with a start]
- The Doctor: Morning.
- Heidi: What happened?
- The Doctor: The big bang, dinosaurs, bipeds, and a mounting sense of futility.
- The Doctor: Do babies die with honour?
- [translating the baby's cries]
- The Doctor: 'I am afraid, Mother. Hold me, Mother, I am afraid.'
- Clara Oswald: Um, he speaks baby.
- The Doctor: [continues translating] 'Turn your face towards me, Mother. For you're... you're beautiful. And I will sing for you. I am afraid, but I will sing.'
- The Doctor: [leading sword practice among the Vikings] So, when I say 'move' you move! When I say 'jump' you say, 'How high?' Unless there's, of course, a gap of some kind, which of course means you jump horizontally.
- [a tall Viking raises his hand]
- The Doctor: Yes, what is it, Lofty?
- Lofty: Sir, my name's not actually Lofty. It's...
- The Doctor: No, it's not. It's 'Lofty' - I've got too much to think about without everybody having their own names, so it's 'Lofty.'
- [points to him]
- The Doctor: You're 'Lofty.'
- [points to a Viking with long hair]
- The Doctor: You're Daphne,
- [points to a Viking with an oversized helmet]
- The Doctor: you're Noggin-the-Nog,
- [points to a bald Viking]
- The Doctor: ZZ Top,
- [points to one with braids]
- The Doctor: and you're, uh, Heidi.
- [last lines]
- Clara Oswald: Whatever you did for Ashildr, I think she deserved it.
- The Doctor: Yes. Yes, she did. But Ashildr isn't just human any more. A little piece of alien inside her, so in a way she's... in a way... she's a hybrid.
- [first lines]
- Clara Oswald: Doctor! Doctor!
- The Doctor: You're the very next thing on the list.
- Clara Oswald: Doctor! Help me!
- The Doctor: Clara, I'm under attack from four and a bit battle fleets, in case you think I'm slacking.
- The Doctor: [Clara has just been beamed from the Mire's ship] Clara! Clara!
- [He stops running towards her and gives her a thumbs-up]
- The Doctor: I'm not a hugger.
- [He swoops her up and twirls her around]
- The Doctor: Oh, and this is not a hug!
- [in a deleted scene]
- The Doctor: Give me 20 good soldiers and I can win any battle.
- Clara Oswald: Who said that?
- The Doctor: I did. How did it sound?
- Clara Oswald: We don't have 20 good soldiers. You've got the Vikings' answer to Dad's Army.