Jeff Jeffries (James Stewart) is confined to his apartment by a broken leg. The rear window of his apartment faces a courtyard where he can see into windows of neighboring apartments. His only contacts with the outside world, though, are restricted to his visiting nurse, Stella (Thelma Ritter), his girlfriend, Lisa (Grace Kelly), and his policeman friend (Wendell Corey). Because he's so bored, Jeff starts using binoculars to spy on his neighbors. Then, one night, he becomes convinced that the man across the way, Lars Thorvald (Raymond Burr) has murdered his invalid wife and smuggled her body out in pieces. At first Lisa and Stella don't believe his stories, but later they become convinced that there is some merit to what he's been saying. He enlists them to do a bit of sleuthing for him. Lisa scares him when he sees her exploring the man's apartment. During the time she's gone, Thorvald visits Jeff's apartment and makes threats. He then catches Lisa in his apartment. Jeff calls the police, but watches helplessly as Lisa works to save herself from Thorvald.