Two young men strangle their "inferior" classmate, hide his body in their apartment, and invite his friends and family to a dinner party as a means to challenge the "perfection" of their crime.

Mrs. Atwater: Do you know when I was a girl I used to read quite a bit.
Brandon: We all do strange things in our childhood.
Brandon: I've always wished for more artistic talent. Well, murder can be an art, too. The power to kill can be just as satisfying as the power to create.
Brandon: What are you doing?
Rupert Cadell: It's not what I'm going to do, Brandon. It's what society is going to do. I don't know what that will be, but I can guess, and I can help. You're going to die, Brandon. Both of you. You are going to die.
[opens a window and fires three shots]
Rupert Cadell: Brandon's spoken of you.
Janet Walker: Did he do me justice?
Rupert Cadell: Do you deserve justice?
Phillip Morgan: Rupert only publishes books HE likes... usually philosophy.
Janet Walker: Oh. Small print, big words, no sales.
Brandon Shaw: Rupert's extremely radical. Do you know that he selects his books on the assumption that people not only can read but actually can think?
Brandon Shaw: Good and evil, right and wrong were invented for the ordinary average man, the inferior man, because he needs them.
Brandon: Nobody commits a murder just for the experiment of committing it. Nobody except us.
Rupert Cadell: [Phillip and Brandon have been arguing about strangling chickens] Personally, I think a chicken is as good a reason for murder as a blonde, a mattress full of dollar bills or any of the customary, unimaginative reasons.
Janet Walker: Well, now, you don't really approve of murder, Rupert? If I may?
Rupert Cadell: You may... and I do. Think of the problems it would solve: unemployment, poverty, standing in line for theatre tickets...
Brandon Shaw: Determined to get drunk, aren't you?
Phillip Morgan: I am drunk.
Brandon Shaw: And just as childish as you were before when you called me a liar.
Phillip Morgan: You had no business telling that story.
Brandon Shaw: Why did you lie anyway?
Phillip Morgan: I had to! Have you ever bothered for just one minute to understand how someone else might feel?
Brandon Shaw: I'm not sentimental if that's what you...
Phillip Morgan: No, that's not what I mean; but it doesn't matter. Nothing matters... except that Mr. Brandon liked the party. Mr. Brandon gave the party. Mr. Brandon had a delightful evening. Well, I had a rotten evening!
Brandon Shaw: Keep drinking, and you'll have a worse morning.
Phillip Morgan: At least if I have a hangover, it'll be all mine!
Brandon: We killed for the sake of danger and for the sake of killing.
Brandon Shaw: Of course, he was a Harvard graduate. That might be grounds for justifiable homicide.
Brandon Shaw: Mrs. Wilson, champagne!
Kenneth: Oh, it isn't someone's birthday is it?
Brandon Shaw: Don't look so worried, Kenneth. It's, uh, really almost the opposite.
Brandon: But why should I want to come back?
Phillip Morgan: Yes, why?
Brandon: For the pleasure of our company, or another drink?
Rupert Cadell: That's a very good idea. May I have one for the road?
Phillip Morgan: I never strangled a chicken in my life!
Brandon Shaw: It is a little difficult trying to keep up with your romances. After me came Kenneth, now it's David. Why the, the switch from Kenneth to David anyway?
Janet Walker: Obviously I think he's nicer.
Brandon Shaw: Well, he's certainly richer.
Janet Walker: That's a new low... even for you, chum.
Rupert Cadell: Did you think you were God, Brandon?
Brandon Shaw: I've always thought that it was out of character for David to drink anything as corrupt as Whiskey.
Phillip Morgan: Out of character for him to be murdered, too.
Rupert Cadell: You're quite a good chicken strangler as I recall.
Brandon: That's where we're superior, Phillip. We have courage. Rupert doesn't.
Mrs. Wilson - Their Housekeeper: [placing a tray of food on the table] Mr. Cadell got a bad leg in the war for his courage. And you've got your sleeve in the celery, Mr. Phillip.
Brandon: The good Americans usually die young on the battlefield, don't they? Well, the Davids of this world merely occupy space, which is why he was the perfect victim for the perfect murder. Course he, uh, he was a Harvard undergraduate. That might make it justifiable homicide.
Rupert Cadell: Well well well Kenneth Lawrence, how you've grown.
Kenneth: Hello ,uh, Mr...
Rupert Cadell: Come on, Ken. School's out, you can say it.
Kenneth: Rupert, you're the same as ever. It's awfully good to see you again.
Rupert Cadell: Why?
[last lines]
Phillip Morgan: They're coming.
Brandon: [David screams, to Phillip] Open it.
[they put David in the trunk and close it]
Brandon: Now look, I'm not going to get caught because of you or anyone else. Nobody is going to get in my way now.
Rupert Cadell: After all, murder is - or should be - an art. Not one of the 'seven lively', perhaps, but an art nevertheless. And, as such, the privilege of committing it should be reserved for those few who are really superior individuals.
Brandon Shaw: And the victims: inferior beings whose lives are unimportant anyway.
Rupert Cadell: Obviously. Now, mind you, I don't hold with the extremists who feel that there should be open season for murder all year round. No, personally, I would prefer to have..."Cut a Throat Week"... or, uh, "Strangulation Day"...
Janet Walker: [referring to Brandon] Why can't he keep his hands off people?
Rupert Cadell: By what right do you dare to say that there's a superior few to which you belong?