Based on a novel by Vera Caspary, a detective searches for the murderer of a beautiful woman.
Detective Mark McPherson (Dana Andrews) investigates the murder of Laura Hunt and questions writer Waldo Lydecker (Clifton Webb), who asks to accompany him. They visit Laura's aunt Ann Treadwell (Judith Anderson). Mark asks her why she gave money to Shelby Carpenter (Vincent Price), who comes out of her bedroom. Shelby goes with Mark and Waldo to Laura's apartment and is caught in a lie about having a key.
At a restaurant Waldo tells Mark how he met Laura (Gene Tierney) five years before. Laura asks him to endorse a pen, but he treats her with contempt. Waldo goes to Laura in her office, apologizes, endorses the pen, and makes a date. Waldo says he helped Laura get clients, but Laura stopped visiting him. Waldo sees a man in her apartment and criticizes him in his column. At Ann's party Waldo and Laura meet Shelby, and Laura offers him a job. Shelby goes out with Laura. Waldo tells Laura bad things Shelby has done and of his relationships with Diane Redfern and Ann. Laura says she plans to marry Shelby, but Waldo helps her find Shelby with Ann. Waldo says he never saw Laura again.
Mark learns that Laura's housekeeper Bessie Clary (Dorothy Adams) removed liquor from the crime scene. Mark examines Laura's things, and Waldo comes in, accusing Mark of being in love with the dead Laura. Waldo leaves, and Mark falls asleep in the chair. Laura comes in and says she was in the country. Laura finds a dress of Diane Redfern's. Mark questions Laura and tells her not to leave or make a call. Laura says she decided not to marry Shelby. By a tap on her phone, Mark hears Laura call Shelby. At her house Mark questions Shelby about her shotgun. Shelby says he had Diane answer the door at Laura's apartment and heard a shot.
Mark takes groceries to Laura for breakfast. Bessie comes in and screams. Shelby brings Laura a flower and kisses her, making Mark jealous. Waldo comes in, sees Laura, and collapses. Waldo wants Mark to arrest Shelby, but Mark changes his mind. Ann asks Shelby to marry her. Shelby tells Laura that he had to hide her shotgun. Ann tells Laura to give up Shelby for Mark. Mark arrests Laura and punches Shelby in the stomach. Mark interrogates Laura about Shelby and then takes her home. Mark goes into Waldo's apartment and breaks into his clock. Waldo tells Laura that Mark is not a warm person. Mark comes in and tells Laura that her shotgun was not the murder weapon. Laura tells Waldo that she does not want to see him anymore. In Waldo's clock in her apartment Mark finds a shotgun, and he explains to Laura how Waldo shot Diane. Mark puts the gun back and goes to arrest Waldo, kissing Laura goodbye. Waldo sneaks in to get the gun. Laura turns on the radio to hear Waldo's program. Waldo loads the gun. Laura pushes the gun aside and runs. Mark breaks in, and the cop with him shoots Waldo.
Waldo's cynical character seems to have been based on
the critic Alexander Woollcott, and this mystery suggests that
the way a writer presents oneself may be quite different from
the reality.