- [Inspector Russell and Alice Norton's fiancee are questioning John after he fatally attacks Mildred]
- Jimmy Kane: We heard a woman screaming.
- John Harrington: Screaming?
- Inspector Russell: Yes. We certainly heard.
- John Harrington: Oh, Inspector! You're allowing yourself to be influenced by a very impressionable young man, I'm surprised at you. It's not worthy of you, you know.
- [John motions Russell and Kane to his living room TV set, and turns it on to a broadcast of "Black Sabbath"]
- Maria: [from the TV] No... no, don't touch me! Leave me alone!
- [she is greeted by Gorca - Boris Karloff - and she screams multiple times as he approaches her]
- John Harrington: Were these the screams you heard?
- Inspector Russell: Very interesting. You like horror films, do you? I don't find them very entertaining. I keep thinking that... reality is more terrifying than fiction.
- [first lines]
- Mildred Harrington: John? John!
- John Harrington: [shaving] Just a minute, Mildred.
- John Harrington: [voice-over] My name is John Harrington. I'm 30 years old. I am a paranoiac. Hmph... "paranoiac". An enchanting word. So civilized, and full of possibilities. The truth is, I am completely mad... the realization which annoyed me at first, but is now amusing to me. Quite amusing. Nobody suspects I am a madman... a dangerous murderer. Not Mildred, my wife... nor the employees of my fashion center... nor, of course, my customers.
- [scoops a fly out of his drink]
- John Harrington: Poor little fly. Why are you so daring? You're so fragile... and yet you're born, you reproduce yourself, and you die, like man. The difference is that you don't think, and you don't need to remember. You don't fear death because you ignore it. Your insignificant life is a mere biological accident. But death exists, I can assure you, and that's what makes life a ridiculous and brief drama.
- [feeds the fly to his pet parrot]
- John Harrington: But the fact remains that I have killed five young women, three of whom are buried in the hothouse: Carol, Mary, Margaret. They were the friendliest, the most attractive ones. There is one problem. I must go on wielding the cleaver. It's most annoying. But when I begin to hear the footsteps... those stealthy footsteps... I know I must kill. And I shall have to keep on killing, until I find out the whole truth. That's it: until I find out the whole truth.
- John Harrington: [narrating] Do you hear those footsteps? Someone is tip-toeing inside my brain. Who? Why do I hear those footsteps?
- Helen Wood: I'm just an ordinary girl: I adore luxury, and I'm terribly lazy. And I like to amuse myself doing terribly crazy things!
- John Harrington: Oh? What kind of things?
- Helen Wood: Well - I just turned twenty-three, and I've had several lovers!
- John Harrington: How many lovers have you had?
- Helen Wood: Oh, I've never counted. Not many. Why aren't you happily married?
- John Harrington: Every man needs women for different reasons... apart from love.
- Helen Wood: Apart from love, why do you need them?
- John Harrington: Perhaps... to find out something about myself.
- Helen Wood: You know I could help you find out about yourself.
- John Harrington: I wouldn't want to... to use you in that way.