In the next part of their revealing conversation, Jeff points out a similarity between the apartments of Lisa and the in-shape young dancer dubbed 'Miss Torso' (Georgine Darcy) [nicknamed with a dismembered body part, a strange name given the subject of the film] who is serving drinks and entertaining three male suitors in her apartment. In the midst of their own domestic crisis, both of them use the experience of viewing 'Miss Torso's' apartment to make cutting remarks toward each other about their own strained relationship:

Jeff: ...but we have a little apartment here that's probably about as popular as yours. You remember of course 'Miss Torso,' the ballet dancer. She's like a Queen Bee with her pick of the drones.
Lisa (changing the metaphor): I'd say she's doing a woman's hardest job - Juggling Wolves.
Jeff (watching 'Miss Torso' briefly kiss one of the men on the balcony and attempting to go back inside while he restrains her): She picked the most prosperous-looking one.
Lisa: She's not in love with him or any of them.
Jeff: How can you tell that from here?
Lisa: You said it resembled my apartment, didn't you?

The blinds are still closed on the newly-wed couple. The heavy-set, morose-looking, costume-jewelry salesman Thorwald serves his bed-ridden, invalid, nagging sick wife a tray of dinner (as she angrily snipes: "Well, I hope they're cooked this time.") [Also, a siren grows louder in the background (a foreboding suggestion of an emergency or disaster about to happen).] She tosses away the rose he has placed on the meal tray, symbolic of their unhappy marriage. Then while on the telephone in the living room, the wife gets out of bed and listens to his conversation, mocking him. They argue after she overhears what must be a covert phone conversation he has had with a clandestine lover. [This is the last time the salesman's wife is seen, before her presumed murder.]

[All three women are distorted, possible identities or pathways for Lisa's and Jeff's 'relationship.' The variety of characters visible through his rear window exteriorize the tensions and dynamics of their own lives.]

A middle-aged bachelor, composer/songwriter (Ross Bagdasarian) struggles as he plays at his piano in his posh studio apartment - a man behind him repairs a clock [Director Hitchcock gives his customary cameo appearance]. When served dinner by Lisa, to the accompaniment of the composer's music, Jeff makes a discordant comment about how her high-style dress, manners, and dinner service are beyond him - reminiscent of his earlier complaint voiced with Stella:

Lisa (referring to the composer's music): It's enchanting. It's almost as if it were being written especially for us.
Jeff (referring to the struggle he is having composing): No wonder he's having so much trouble with it.
Lisa: At least you can't say the dinner isn't right.
Jeff (exasperated): Lisa, it's perfect, as always.

Following dinner, they argue about the possibility of living together peacefully. She is eager to get a commitment from her reluctant boyfriend, but it would mean he'd have to abandon his career. Jeff is unable and unwilling to compromise and consider any different life style other than his own freewheeling, traveling life of hardship. In fact, he is traumatized by the thought of marriage and giving up his profession as a traveling photographer (or 'voyeur' actually). He argues that she wouldn't fit in and would become an encumbrance to his freedom. During their rough and stormy argument, they appear on the verge of breaking up for good:

Lisa: There can't be that much difference between people and the way they live. We all eat, talk, drink, laugh, wear clothes...
Jeff: Well, now look, now look...
Lisa: If you're saying all this because you don't want to tell me the truth, because you're hiding something from me, then maybe I can understand.
Jeff: I'm not hiding anything! It's just that...
Lisa: It doesn't make sense! What's so different about it here from over there, or any place you go, that one person couldn't live in both places just as easily?
Jeff: Some people can. Now if you'll just let me explain...
Lisa: What is it but traveling from one place to another taking pictures? It's just like being a tourist on an endless vacation.
Jeff: OK. Now that's your opinion. You're entitled to it. Now let me give you my side...
Lisa: It's ridiculous to say that it can only be done by a special, private little group of anointed people...
Jeff: I made a simple statement, a true statement, but I can back it up if you'll just shut up for a minute!
Lisa: If your opinion is as rude as your manner, I don't think I care to hear it.
Jeff: Oh, come on now, simmer down.
Lisa: You - I can't fit in here - you can't fit in there. I mean, according to you, people should be born, live and die on the same spot.
Jeff: SHUT UP! Did you ever eat fish heads in rice?
Lisa: Of course not.
Jeff: Well, you might have to if you went with me. Did you ever try to keep warm on a C-54 at 15,000 feet, 20 degrees below zero?
Lisa: Oh, I do it all the time. Whenever I have a few minutes after lunch.
Jeff: Did you ever get shot at? Did you ever get run over? Did you ever get sandbagged at night because somebody got unfavorable publicity from your camera? Did you ever...those high-heels, they'll be great in the jungle and the nylons and those six ounce lingerie...
Lisa: Three!
Jeff: All right. Three! They'll make a big hit in Finland just before you freeze to death?
Lisa: Well, if there's one thing I know, it's how to wear the proper clothes.
Jeff: Yeah, yeah. Well try and find a raincoat in Brazil, even when it isn't raining. Lisa. In this job, you carry one suitcase, your home is the available transportation. You don't sleep very much, you bathe less, and sometimes the food that you eat is made from things that you couldn't even look at when they're alive.
Lisa: Jeff, you don't have to be deliberately repulsive just to impress me I'm wrong.
Jeff: Deliberately repulsive! I'm just trying to make it sound good. You just have to face it, Lisa, you're not meant for that kind of a life. Few people are.
Lisa: You're too stubborn to argue with.
Jeff: I'm not stubborn - I'm just truthful.
Lisa: I know, a lesser man would have told me it was one long holiday - and I would have been awakened to a rude disillusionment.
Jeff: Oh, well now, wait a minute. Now wait a minute. If you want to get vicious on this, I'll be very happy to accommodate you.
Lisa: No, I don't particularly want that. (She rises and moves away.) So that's it. You won't stay here and I can't go with you.
Jeff: It would be the wrong thing.
Lisa: You don't think either one of us could ever change?
Jeff: Right now, it doesn't seem so.
Lisa (preparing to leave, she begins to put on her long white gloves that she removed when she arrived): I'm in love with you. I don't care what you do for a living. I'd just like to be part of it somehow. It's deflating to find out the only way I can be part of it is to take out a subscription to your magazine. I guess I'm not the girl I thought I was.
Jeff: There's nothing wrong with you, Lisa. You've got this town in the palm of your hand.
Lisa: Not quite it seems. (She puts on her white scarf.) Goodbye, Jeff. (She turns and starts for the doorway)
Jeff: You mean, 'Good night.'
Lisa (standing in the darkness of the doorway): I mean what I said.
Jeff: Well, Lisa, couldn't we just, uh, couldn't we just keep things status quo?
Lisa: Without any future?
Jeff: Well, when am I gonna see you again?
Lisa (hesitantly): Not for a long time...(pause)...at least not until tomorrow night.

When she goes home, Jeff quietly agonizes for a moment, and then turns toward the peacefulness of his dark apartment courtyard. The darkness is shattered by the sharp sound of a loud female scream and the sound of breaking glass. Later on that night, thunder signals a rainstorm approaching as Jeff dozes next to his window. Watching the neighbors again, he interrupts their privacy by observing their movements:

• The sleeping couple on the fire escape come in from the rain.
• Thorwald leaves his apartment in the pouring rain with his heavy case of sample products at 1:55 am. At 2:35 am, he returns with his case (lighter and presumably empty).
• In the composer's studio, the alcoholic musician staggers in - drunk.
• Thorwald again exits with his heavy sample case.
  Jeff dozes off.
• 'Miss Torso' enters her apartment, while refusing the advances of the same insistent date/one-night stand into her place.
• Thorwald returns with his sample case, again probably empty.
  Jeff dozes off.
• Early the next morning while Jeff sleeps, Thorwald leaves his apartment with an unidentified middle-aged woman dressed in black. [This woman could be Mrs. Thorwald, making all of Jeff's assumptions wrong.]
• During the next day, a workman delivers a block of ice through the alleyway. The female sculptor works on an abstract headless figure of "Hunger" on the ground floor, suggesting both gastronomical and sexual needs. 'Miss Torso' dances while going about her daily chores, and a woman lets her little dog down into Thorwald's garden from the fire escape in a pulley-driven basket.

While Jeff receives a massage from Stella, she jokingly remarks that "the insurance company would be much happier if you'd sleep in bed at night instead of in that wheelchair...Your eyes are all bloodshot. You must have been watching out that window for hours." She is worried that one of the neighbors may catch him - a tell-tale foreboding of the future. Jeff replies that he wouldn't mind if it was 'Miss Torso,' "the eat, drink, and be merry girl."

He tells her about his spying on the neighbors, in particular the mysterious comings and goings on the part of Thorwald the previous stormy night. He questions why he would carry his salesman's sample case at that hour: "Well, what would he be selling at three o'clock in the morning?" Stella quickly jokes with speculation: "Flashlights. Luminous dials for watches. House numbers that light up." On the contrary, Jeff believes "he was taking something out of the apartment." Commenting on Thorwald's bad marriage and how he might "run out on her, the coward," Jeff thinks otherwise: "Sometimes it's worse to stay than it is to run."

As they both look and notice that the shades are no longer down in Thorwald's apartment, Thorwald looks back at them. Jeff cautions Stella to back up out of the light and "get out of sight":

That's no ordinary look. That's the kind of a look a man gives when he's afraid somebody might be watching him.

Thorwald is intensely watching the little dog sniffing around the rose bushes in the flower bed of his garden, until the pet is shooed away by a neighbor. [Initially, in a startling moment, it appears like Thorwald is staring at Jeff's apartment.]

To intrude further into the apartment (beyond merely using his naked eye) when his curiosity increases and he becomes engrossed with the evidence of his alleged murder theory, he asks for Stella to take out his binoculars as she leaves. She warns: "Trouble, I can smell it."

Not satisfied with the binoculars, he reaches for a huge, high-powered telephoto lens - not to take pictures but to observe. [The lens is clearly Hitchcock's version of an optical erection, stimulating and allowing him even greater pleasure in his viewing experience. The cast on his leg is a representation of his impotence - unable to act or perform.] With the lens, he sees Thorwald in his living room replacing sample items into his case. And at his kitchen sink, he is viewed wrapping a large saw blade and a butcher knife in newspaper. He also curiously notes that Thorwald's sick wife is absent from the apartment.

Later that evening, the heat has intensified during the day and it is now 82 degrees. While other neighborly residents go about their routine activities, the camera pans back to Jeff's window, where it finds Jeff and Lisa passionately hugging and kissing in his apartment. She has dressed provocatively and come back to make up with him:

Lisa: How far does a girl have to go before you notice her?
Jeff: Well, if she's pretty enough, she doesn't have to go anywhere. She just has to be.
Lisa: Well, ain't I? Pay attention to me.
Jeff: Well, I'm, I'm not exactly on the other side of the room.
Lisa: Your mind is. When I want a man, I want all of you.

While she kisses, hugs and caresses him, she is overlooked and romantically ignored as Jeff becomes more and more obsessed by his neighbor's activities - his voyeurism and impotence are intrinsically linked. They are on totally different wavelengths: he is more interested in his theories and in telling her about what he witnessed the previous night - than kissing her.

Jeff: Don't, don't you ever have any problems?
Lisa: I have one now.
Jeff: So do I.
Lisa: Tell me about it.
Jeff: Why, why would a man leave his apartment three times on a rainy night with a suitcase and come back three times?
Lisa: He likes the way his wife welcomes him home.
Jeff: Oh no. No, no, no. Not this salesman's wife. And why didn't he go to work today?
Lisa: Homework. It's more interesting.
Jeff: What's interesting about a butcher knife and a small saw wrapped in newspaper? Huh?
Lisa: Nothing, thank heaven.
Jeff: Why hasn't he been in his wife's bedroom all day?
Lisa: I wouldn't dare answer that.
Jeff: Well, listen. I'll answer it, Lisa, there's something terribly wrong.
Lisa: And I'm afraid it's with me. (Lisa leaves him to go to the couch and smoke a cigarette.)
Jeff: What do you think?
Lisa: Something too frightful to utter.
Jeff: He went out a few minutes ago in his undershirt. He hasn't come back yet. That would be a terrible job to tackle. [The camera gazes at 'Miss Torso' at the same time.] Just how would you start to cut up a human body?
Lisa (turning on a lamp light next to her): Jeff, I'll be honest with you. You're beginning to scare me a little.

He interrupts her to say that Thorwald has returned to his apartment, carrying a heavy rope and walking into his wife's shaded bedroom. Thorwald, in silhouette, bows and raises up as if he's working (cutting up?) with something in the bedroom. Unconvinced by Jeff's speculative ideas, Lisa suddenly rises and turns his wheelchair away from the window. She is critical that he has become an obsessed Peeping Tom:

Lisa: Jeff, if you could only see yourself!
Jeff: Whatsa matter?
Lisa: Sitting around looking out of the window to kill time is one thing but doing it the way you are with binoculars and wild opinions about every little thing you see is, is diseased!
Jeff: What do you think I consider it - recreation?
Lisa: I don't know what you consider it, but if you don't stop it, I'm getting out of here...What is it you're looking for?

Jeff argues that he is only concerned about the salesman's invalid wife, and that doesn't make him "sound like a madman." Lisa offers a logical reason for why the invalid wife hasn't been attended to all day: "Maybe she died." Jeff pursues her line of reasoning: "Where's the doctor? Where's the undertaker?" Lisa insists that she may be sleeping or "under sedatives." She believes Jeff is irresponsible and wildly speculating, and that "there is nothing to see." Lisa firmly grabs hold of his wheelchair so that he can't turn it around to take a look. Jeff thinks that there is something to see:

Jeff: I've seen it through that window. I've seen bickering and family quarrels and mysterious trips at night, knives and saws and ropes, and now since last evening, not a sign of the wife. All right, now you tell me where she is...
Lisa: Maybe he's leaving his wife, I don't know, I don't care. Lots of people have knives and saws and ropes around their houses and lots of men don't speak to their wives all day. Lots of wives nag and men hate them and trouble starts. But very very few of them end up in murder if that's what you're thinking.
Jeff: It's pretty hard for you to keep away from that word isn't it?
Lisa: You could see all that he did, couldn't you?
Jeff: Of course, I...
Lisa: You could see because the shades were up and, and he walked along the corridor and the street and the back yard. Oh Jeff, do you think a murderer would let you see all that? That he wouldn't pull the shades down and hide behind them?
Jeff: Just where he's being clever. He's being non-chalant about things...
Lisa: Oh, and that's where you're not being clever. A murderer would never parade his crime in front of an open window.
Jeff: Why not?
Lisa (pointing to the newlyweds' window): Why, for all you know, there's probably something a lot more sinister going on behind those windows.
Jeff: Where? (He smiles) Oh, no comment.

The two of them watch Thorwald tie up a very large wooden crate with a rope, in front of a rolled-up mattress in his wife's bedroom. Lisa is suddenly an intrigued convert to Jeff's point of view. She instinctively realizes that the key to his heart is through his eyes. Significantly, their relationship is suddenly sparked into life and transfigured, and she joins him in an unexpected turnabout. Lisa concludes that his insane, sinister, and imaginative conclusions may be accurate:

Let's start from the beginning again, Jeff. Tell me everything you saw...and what...you think it means.

Much later that night, Lisa (who serves as Jeff's legs) calls to tell him the name and address of the salesman from his apartment letterbox:

The name on the second floor rear mailbox reads Mr. and Mrs. Lars, that's L-A-R-S, Lars Thorwald...125 West 9th Street.

When she asks what Thorward is doing now, Jeff replies (with a deeply ironic statement that actually describes himself): "He's just sitting in the living room in the dark. Hasn't gone near the bedroom." The next morning, Jeff tells New York police detective buddy Thomas J. Doyle (Wendell Corey) on the phone that there is "a little neighborhood murder" that he should come over and investigate. After serving him breakfast, Stella speculates comically about the gruesome, morbid details of how Thorwald disposed of the body:

Just where do you suppose he cut her up? 'Course, the bathtub! That's the only place where he could have washed away the blood. (Jeff looks uneasy and pauses during his meal. He puts down his fork. He nearly chokes on his coffee during Stella's next line.) He better get that trunk out of there before it starts to leak.

Jeff sees 'Miss Torso' hanging out intimate undergarments on her outside clothesline. The t-shirt-clad bridegroom opens the shade of the newlywed's room and leans out, getting some fresh air. His bride calls him back: "Har-ry?" Stella and Jeff watch two parcel-post delivery men arrive at Thorwald's apartment to pick up the wooden crate. Stella runs down to get the name of the freight company from the side of the truck, but she gestures from the alley back to Jeff that she was unsuccessful.

In the next scene, plainclothes cop Tom has arrived. He views the apartment across the courtyard through Jeff's binoculars, but is skeptical of Jeff's theories and deductions about the missing wife. He rebuffs and dismisses his friend's findings, calling them inadequate and full of misinterpreted evidence:

Tom: Didn't see the killing or the body. How do you know there was a murder?
Jeff: Because everything this fella's done has been suspicious. Trips at night in the rain, and knives and saws and trunks with rope, and now this wife that isn't there anymore.
Tom: I admit it all has a mysterious sound. Could be any number of things - murder's the least possible.
Jeff: Well, don't tell me he's an unemployed magician amusing the neighborhood with his sleight-of-hand. Now don't tell me that.
Tom: It's too obvious, a stupid way to commit murder in full view of fifty windows? Then sit over there smoking a cigar, waiting for the police to come and pick him up?
Jeff: Officer, go do your duty. Go pick him up!
Tom: Jeff, you've got a lot to learn about homicide. Why, morons have committed murder so shrewdly it's taken a hundred trained police minds to catch them. That salesman wouldn't just knock his wife off after dinner and toss her in the trunk and put her in storage.
Jeff: I'll bet it's been done.
Tom: Most everything's been done - under PANIC. This is a thousand to one shot. He's still sitting around the apartment. That man's not panicked.
Jeff: You think I made all this up, huh?

Tom believes there must be "a very simple explanation" for everything. Laconically, the detective promises to "poke into it a little" on his own before reporting it to the department, finding out where the wife's "trip" took her. After he leaves, Jeff again peers over his window sill, and notices the little dog furiously digging around the rose bushes in the garden. Thorwald approaches the dog and pats it on its way: "Get along." In a parallel shot, Jeff sees the detective through the alley way loitering and 'sniffing around.'