During World War II, mathematician Alan Turing tries to crack the enigma code with help from fellow mathematicians.

Alan Turing: Do you know why people like violence? It is because it feels good. Humans find violence deeply satisfying. But remove the satisfaction, and the act becomes... hollow.
Joan Clarke: Do you know, this morning I was on a train that went through a city that wouldn't exist if it wasn't for you. I bought a ticket from a man who would likely be dead if it wasn't for you. I read up, on my work, a whole field of scientific inquiry that only exists because of you. Now, if you wish you could have been normal... I can promise you I do not. The world is an infinitely better place precisely because you weren't.
Alan Turing: When people talk to each other, they never say what they mean.
[pause]
Alan Turing: They say something else and you're expected to just know what they mean.
Final quotes: His machine was never perfected, though it generated a whole field of research into what became known as "Turing Machines". Today we call them "computers".
Joan Clarke: I know it's not ordinary. But who ever loved ordinary?
Joan Clarke: Alan, what's happened?
Alan Turing: [pause] We can't be engaged anymore. Your parents need to take you back. Find you a husband elsewhere.
Joan Clarke: What's wrong with you?
Alan Turing: I have something to tell you. I'm... I'm a homosexual.
Joan Clarke: Alright.
Alan Turing: No, no, men, Joan. Not women.
Joan Clarke: So what?
Alan Turing: I just told you...
Joan Clarke: So what? I had my suspicions. I always did. But we're not like other people. We love each other in our own way, and we can have the life together that we want. You won't be the perfect husband? I can promise you I harboured no intention of being the perfect wife. I'll not be fixing your lamb all day, while you come home from the office, will I? I'll work. You'll work. And we'll have each other's company. We'll have each other's minds. Sounds like a better marriage than most. Because I care for you. And you care for me. And we understand one another more than anyone else ever has.
Alan Turing: I don't.
Joan Clarke: What?
Alan Turing: Care for you. I never did. I just needed you to break Enigma. I've done that now, so you can go.
Joan Clarke: [slaps him] I am not going anywhere. I have spent entirely too much of my life worried about what you think of me, or what my parents think of me, or what the boys in Hut 8 or the girls in Hut 3 think, and you know I am done. This work is the most important thing I will ever do. And no one will stop me. Least of all you.
[pause]
Joan Clarke: You know what? They were right. Peter. Hugh. John. You really are a monster.
Alan Turing: Are you paying attention? Good. If you are not listening carefully, you will miss things. Important things. I will not pause, I will not repeat myself, and you will not interrupt me. You think that because you're sitting where you are, and I am sitting where I am, that you are in control of what is about to happen. You're mistaken. I am in control, because I know things that you do not know.
[pause]
Alan Turing: What I will need from you now is a commitment. You will listen closely, and you will not judge me until I am finished. If you cannot commit to this, then please leave the room. But if you choose to stay, remember you chose to be here. What happens from this moment forward is not my responsibility. It's yours. Pay attention.
John Cairncross: The boys, we're going to get some lunch.
[no response]
John Cairncross: Alan?
Alan Turing: Yes?
John Cairncross: I said we're going to get some lunch.
[no response]
John Cairncross: Alan?
Alan Turing: Yes?
John Cairncross: Can you hear me?
Alan Turing: Yes.
John Cairncross: I said we're off to get some lu-...
[disrupts himself]
John Cairncross: This is starting to get a little bit repetitive.
Alan Turing: What is?
John Cairncross: I had asked, if you wanted to come have lunch with us.
Alan Turing: No, you didn't, you said you were going to get some lunch.
John Cairncross: Have I offended you in some way?
Alan Turing: Why would you think that?
John Cairncross: Would you like to come to lunch with us?
Alan Turing: What time's lunch time?
Hugh Alexander: [Frustrated] Christ, Alan, it's a bleeding sandwich.
Alan Turing: What is?
Hugh Alexander: Lunch.
Alan Turing: Oh, I don't like sandwiches.
John Cairncross: Nevermind.
Alan Turing: I like solving problems, Commander. And Enigma is the most difficult problem in the world.
Commander Denniston: Enigma isn't difficult, it's impossible. The Americans, the Russians, the French, the Germans, everyone thinks Enigma is unbreakable.
Alan Turing: Good. Let me try and we'll know for sure, won't we?
Alan Turing: Of course machines can't think as people do. A machine is different from a person. Hence, they think differently. The interesting question is, just because something, uh... thinks differently from you, does that mean it's not thinking? Well, we allow for humans to have such divergences from one another. You like strawberries, I hate ice-skating, you cry at sad films, I am allergic to pollen. What is the point of... different tastes, different... preferences, if not, to say that our brains work differently, that we think differently? And if we can say that about one another, then why can't we say the same thing for brains... built of copper and wire, steel?
[first lines]
Alan Turing: Are you paying attention?
Stewart Menzies: [candidates are taking a timed test] Six minutes... is that even possible?
Alan Turing: No, it takes me eight.
Joan Clarke: [raises her hand]
Alan Turing: You're finished?... Five minutes thirty four seconds.
Joan Clarke: You said to finish under six minutes.
Joan Clarke: No one normal could have done that. Do you know, this morning... I was on a train that went through a city that wouldn't exist if it wasn't for you. I bought a ticket from a man who would likely be dead if it wasn't for you. I read up on my work... a whole field of scientific inquiry that only exists because of you.
[pause]
Joan Clarke: Now, if you wish you could have been normal... I can promise you I do not. The world is an infinitely better place precisely because you weren't.
Alan Turing: Was I God? No. Because God didn't win the war. We did.
Hugh Alexander: If you run the wires across the plugboard matrix diagonally, you'll eliminate rotor positions 500 times faster.
Alan Turing: This is actually not an entirely terrible idea.
Joan Clarke: That's Alan for "thank you."
Joan Clarke: So what? I had my suspicions. I always did. But we're not like other people. We love each other in our own way, and we can still live the life together that we want. You won't be the perfect husband? I can promise you I harboured no intention of being the perfect wife. I'll not be fixing your lamb all day awaiting your return from the office, will I? I'll work. You'll work. We'll have each other's company. We'll have each other's minds. Sounds like a better marriage than most. Because I care for you. And you care for me. And we understand one another more than anyone else ever has.
Alan Turing: [Explaining the Turing Test] "The Imitation Game."
Detective Robert Nock: Right, that's... that's what it's about?
Alan Turing: Would you like to play?
Detective Robert Nock: Play?
Alan Turing: It's a game. A test of sorts. For determining whether something is a... a machine or a human being.
Detective Robert Nock: How do I play?
Alan Turing: Well, there's a judge and a subject, and... the judge asks questions and, depending on the subject's answers, determines who he is talking with... what he is talking with, and, um... All you have to do is ask me a question.
Alan Turing: Advise about keeping secrets: it's a lot easier if you don't know them in the first place.
Alan Turing: Hardest time to lie to somebody is when they're expecting to be lied to.
Alan Turing: [after telling the story] Now you decide am I a machine,am I a human,am I a war hero,or am I a criminal.
Detective Robert Nock: I'm not the person to answer that.
Alan Turing: Then you're of no use to me whatsoever.
Alan Turing: Uh, that's my sandwich.
Hugh Alexander: You don't like sandwiches.
Alan Turing: It wasn't just programmable, it was reprogrammable.
Alan Turing: Think of it. A digital computer. Electrical brain.
Stewart Menzies: Oh, Alan... we're gonna have such a wonderful war together.
Stewart Menzies: Mr Turing, do you know how many people have died because of Enigma?
Alan Turing: No, I don't.
Stewart Menzies: Three.
Alan Turing: Three?
Stewart Menzies: While we've been having this conversation.
Stewart Menzies: [he looks at his watch] Oh look, there's another. I rather hope he didn't have a family.
Alan Turing: You will never understand the importance of what I am creating here!
Hugh Alexander: Damn you, you and your machine.
Commander Denniston: This is Stewart Menzies. MI6.
Charles Richards: There are only five divisions of military intelligence. There is no MI6.
Stewart Menzies: Exactly. That's the spirit.
Alan Turing: He likes you.
Joan Clarke: Yes.
Alan Turing: You - you got him to like you.
Joan Clarke: Yes.
Alan Turing: Why?
Joan Clarke: Because I'm a woman in a man's job, and I don't have the luxury of being an ass.
John Cairncross: What's wrong?
Alan Turing: What if... what if I don't fancy being with Joan in that way?
John Cairncross: Because you're a homosexual? I suspected.
Alan Turing: Sh- should I tell her that I've had affairs with men?
John Cairncross: You know, in my admittedly limited experience, women tend to be a bit touchy about accidentally marrying homosexuals. Perhaps not spreading this information about might be in your best interest.
Alan Turing: I care for her, I truly do, but... I-I just don't know if I can pretend...
John Cairncross: You can't tell anyone, Alan. It's illegal. And Denniston is looking for any excuse he can to put you away.
Alan Turing: I know.
John Cairncross: This has to stay a secret.
Peter Hilton: You're not God, Alan. You don't get to decide who lives and who dies.
Alan Turing: Even a broken clock is right twice a day.
Detective Robert Nock: Mr Turing, can I tell you a secret?
Alan Turing: I'm quite good with those.
Detective Robert Nock: I'm here to help you.
Alan Turing: Oh, clearly!
Detective Robert Nock: Can machines think?
Alan Turing: Oh, so you've read some of my published works?
Detective Robert Nock: What makes you say that?
Alan Turing: Oh, because I'm sitting in a police station, accused of entreating a young man to touch my penis, and you've just asked me if machines can think.
Detective Robert Nock: Well, can they? Could machines ever think as human beings do?
Alan Turing: Most people say not.
Detective Robert Nock: You're not most people.
Alan Turing: Codes are a puzzle. A game, just like any other game.
Stewart Menzies: Why are you telling me this ?
Alan Turing: We need your help, to keep this a secret from Admiralty, Army, RAF. Ah... as no one can know, that we've broken enigma, not even
[Commander]
Alan Turing: Dennison
Stewart Menzies: Who's in the process of having you fired ?
Joan Clarke: You can take care of that.
Alan Turing: While we develop a system to help you determine how much intelligence to act on. Which ahh attacks to stop, which to let through. Statistical analysis, the minimum number of actions it will take, for us to win the war - but the maximum number we can take, before the Germans get suspicious
Stewart Menzies: And you're going to trust of this all to statistics ? To maths ?
Alan Turing: Correct.
Joan Clarke: And then MI6 can come up with the lies we will tell everyone else
Alan Turing: You'll need a believable alternative source for all the pieces of information that you use
Joan Clarke: A false story, so that we can explain how we got our information, that has nothing to do with Enigma, and then you can leak those stories to the Germans
Alan Turing: And then to our own military
Stewart Menzies: Maintain a conspiracy of lies at the very highest levels of govt ?... Sounds right up my alley.
Commander Denniston: Well, you realize that six hundred miles away from London there's this nasty little chap called Hitler who wants to engulf Europe in tyranny.
Alan Turing: Politics isn't really my area of expertise.
Hugh Alexander: You know to pull off this irascible genius routine, one has to actually be a genius.
Hugh Alexander: Because there's nothing like a friend's engagement to make a woman want to do something that she'll later regret with the fiancé's better looking chum.
Christopher Morcom: Sometimes it's the very people who no one imagines anything of who do the things no one can imagine.
John Cairncross: If you tell them my secret, I'll tell them yours.