The film starts just inside the triptych of back windows facing a courtyard that connects several apartment buildings in New York City's West Village. The camera then moves through the windows to go outside, scan the busy complex, and then circle back inside to reveal a close-up of L.B. "Jeff" Jefferies (James Stewart) sleeping and sweating profusely - it is a very hot morning. The camera ventures back outside just in time for everyone's alarms to go off, and wanders from window to window, capturing the locals in their getting-ready rituals. Back in Jeff's apartment, we see that he is asleep in a wheelchair with his left leg in a cast. The camera wanders around his apartment, revealing a smashed camera, a stack of magazines, and a number of framed images of exciting and/or dangerous moments, taken from close range.
Jeff is shaving when his phone rings. It is his editor at the magazine where he works, congratulating him for getting his cast off, but Jeff reminds the man that he will be wrapped in plaster for one more week. While Jeff is on the phone, he watches an attractive young woman in a lower-story apartment ("Miss Torso") dance around in her bikini, while a salesman argues with his wife in the apartment directly across from his. Jeff begs his editor to send him back out on assignment, as he is going stir crazy after six weeks inside his apartment. However, his editor refuses to do so until Jeff's leg is healed, saying that he is "too valuable" to the magazine. Over the course of this conversation, Jeff expresses his distaste at the idea of getting married. After hanging up, Jeff watches his neighbors for a while, amused by an older woman with a hearing aid trying to give the salesman, Mr. Thorwald (Raymond Burr), some tips on the flowers he is planting. The salesman shoos her away rudely.
Then, Jeff's chatty nurse, Stella (Thelma Ritter) arrives and warns Jeff about the legal consequences for "Peeping Toms." She tells him that she can smell trouble in the apartment because Jeff keeps watching his neighbors, seeing things he "shouldn't see." While Stella massages him, Jeff confesses that his girlfriend, Lisa, expects him to marry her but he thinks she's too perfect-Park-Avenue for him. He wants someone more "ordinary." Stella urges him not to end the relationship because she is certain that Jeff and Lisa will be able to work out their differences. When Stella retreats into the kitchen, Jeff watches an attractive pair of newlyweds move into an apartment in the adjacent building. They embrace lovingly and then pull the shades closed.
That evening, Jeff's apartment complex is alive and buzzing while he naps close to the window. He is awakened by a kiss from the beautiful Lisa Carol Fremont (Grace Kelly). She is wearing a string of pearls and a beautiful dress straight from Paris. She has ordered delivery of an ornate dinner and a bottle of nice wine from a fancy restaurant and promises that she'll make Jeff's last week in a wheelchair one that he will "never forget." Lisa goes on to tell Jeff about her day of glamorous fittings, fashion shows, and cocktails, while Jeff subtly mocks her. Lisa becomes serious, urging him to leave the magazine and stay in New York - she can get him a job shooting fashion portraits. He tells her to stop "talking nonsense", which clearly upsets her.
While Lisa arranges their dinner, Jeff watches "Miss Lonelyhearts", a woman on the bottom floor of the opposite building, set a table for two even though she is all alone. Miss Lonelyhearts actually sits down and carries on a conversation with a man who does not exist, eventually giving up her charade and laying her head on the table in sorrow. Further upstairs, Miss Torso is now dressed in a glamorous gown, entertaining a gaggle of men with cocktails and laughter. Lisa feels a kinship with Miss Torso, saying that the young blonde is not in love with any of the men that surround her. Jeff watches the salesman bring his wife dinner in bed and, after that, he makes a phone call in the other room. While the salesman is on the phone, his wife gets out of bed; she says something that upsets him. In another apartment, a songwriter plays a beautiful song on the piano.
After dinner, Lisa and Jeff have a serious conversation about the differences between them; he believes that they don't fit into each other's worlds. Lisa describes Jeff's job as being "a tourist on an endless vacation", which he takes as an insult. Jeff goes on to describe the difficult conditions that Lisa would have to endure as his wife; eating strange foods in unfriendly environments, always on the move and often in danger. He doesn't think that she's meant for "that kind of life." They find themselves at an impasse. Jeff's stubbornness frustrates Lisa; she loves him and just wants to be with him. He asks her why they can't just keep seeing each other as they have been, but Lisa doesn't want to be in a relationship with no future, even though she claims that she will be back the following night. After Lisa leaves, Jeff looks out his window; all of his neighbors have gone to sleep. He hears a scream and the sound of glass shattering, but cannot identify the source.
Alfred Hitchcock told Francois Truffaut that Rear Window is a "purely cinematic film." Indeed, from the opening frames, Hitchcock uses a calculated mix of techniques to prepare the viewer for the experience. For starters, the film begins inside Jeff's apartment. This shot introduces the fact that most of Rear Window takes place from Jeff's subjective perspective. He is immobilized, and therefore, our understanding of the events unfolding around him is also limited to what Jeff can see from his fixed station. The camera then goes out into the courtyard, catching glimpses of the everyday lives of Jeff's neighbors. This is the closest Hitchcock gives us to an establishing shot; he is carefully setting the audience up to feel the claustrophobia that is making Jeff so restless. In fact, the production itself likely felt claustrophobic to the people working on the film, as well; the Rear Window set was the largest indoor set ever built at Paramount Studios.
Hitchcock was a master of making his audience relate to his protagonists. By aligning us with Jeff's malaise, we, too, begin to share his curiosity about any possible suspicious behavior; as the film goes on, we even yearn for Thorwald's actions to add up to something sinister. Hitchcock told Truffaut that he thought 9 out of 10 people would do exactly as Jeff does (i.e. watch their neighbors) even though, like Jeff, we know it is wrong. As if to prove this point, Hitchcock's introduction of Jeff makes the viewer into a voyeur, as well. Even though Jeff is asleep, the camera (i.e. the eye of the viewer) glides across his broken leg, and then to his smashed camera, his close-up photographs of fires, explosions, and other death-defying moments, and finally, to several stacks of magazines. With this shot, Hitchcock is telling us everything we need to know about Jeff through images and asking us to put the pieces together. We, then, are no different than Jeff himself.
A MacGuffin is a plot device that motivates a film's characters and advances their motives. Hitchcock often used MacGuffins to show his audience that his films were about more than what they appear to be on the surface. Throughout Rear Window, Jeff's obsession with his neighbors gives him a way to avoid dealing with his own issues. Ultimately, the drama that plays out in Jeff's courtyard is the MacGuffin, while the central conflict of Rear Window is actually the relationship between Lisa and Jeff. The script and structure of this opening sequence supports this. For example, Jeff's editor calls him to find out if he is getting his cast off and can come back to work. However, the subject of their conversation quickly turns to Jeff's bachelor status. When his editor encourages Jeff to settle down and get married, Jeff replies, "Can't you just see me, rushing home to a hot apartment to listen to the automatic laundry and the electric dishwasher and the garbage disposal and the nagging wife?" While Jeff is speaking this line, the camera is focused on the Thorwald's apartment across the courtyard. We see a red and sweaty Mr. Thorwald coming home from work, rolling up his sleeves, and arguing with his wife. Jeff's words are quite literally describing the scene that he is watching unfold; he is watching his anxieties about marriage play out in front of his eyes. This allows Hitchcock to set up the Thorwalds as a way for Jeff to avoid discussing his fear of marriage with Lisa.
Later, when Lisa arrives, her conversation with Jeff about the neighbors is actually about the emotional obstacles that have kept their relationship from moving forward. Jeff points out the sad, single woman downstairs whom he has dubbed "Miss Lonelyhearts", expressing his belief that Lisa could never be in that situation, to which Lisa replies, "oh, you can see my apartment from here?" Below the surface of their conversation, Jeff is insinuating that Lisa will never be lonely, and Lisa is basically replying with, "how do you know?" Jeff then segues to Miss Torso, the beautiful, blonde dancer who always has men falling at her feet. He believes that Lisa's apartment looks more like Miss Torso's, whom he calls "a queen bee with her pick of the drones." Lisa refutes his assessment and points out that Miss Torso does not love any of the men she is with. This time, Jeff asks Lisa how she can tell, and she replies, "you said it resembled my apartment, didn't you?"
In this brief exchange, Hitchcock has presented the main conflict between Jeff and Lisa. Jeff thinks that Lisa can have any man she wants, and can't seem to understand why she would want to be with a poor photojournalist. Meanwhile, Lisa doesn't care about wealth or status. She doesn't want the men who flock around her, vying for her attention. She wants to be with Jeff because she's in love with him and without him, she feels lonely - even when she is surrounded by people. However, over the course of their conversation (just like when his editor and Stella were lecturing him), Jeff can't pay attention to Lisa. He keeps looking out the window, thus proving Stella's point that Peeping Toms should really be looking inward instead of focusing on other people's business. To this point, the late Roger Ebert once said that Jeff is "in love with the occupation of photography, and becomes completely absorbed in reconstructing the images he has seen through his lens. He wants what he can spy at a distance, not what he can hold in his arms."