Jane Craig, the wife of popular detective fiction writer and amateur sleuth Barry Craig, is listening to her husband perform on a radio quiz program when her friend Julie Taylor bursts into the apartment. When Julie tells Jane she suspects that someone is planning a murder at the McCormick Commercial Photography Studio where she is employed, Jane promises to send Barry to investigate as soon as he comes home. Julie then returns to the photography studio and, after leaving a note for Barry, Jane follows her there. When Julie suddenly asks Jane to drop the investigation, Jane accuses her of being in love with her employer, Ralph McCormick. Jane then meets Mac and his two assistants, Kirk Fenley and Harry Duerr, who are engaged in setting up an important photo shoot involving Mrs. Isabel Fleming, a wealthy social leader. As the models take their places, Mrs. Fleming sweeps into the room and refuses to be photographed with Madge Lawrence, one of the models. With no alternative, Ralph dismisses Madge. Barry, meanwhile, arrives home, finds Jane's note and joins her at the studio. A moment later, a scream pierces the air and they trace it to Mrs. Fleming's dressing room, where the dowager lays dead on the floor. Summoned by Mac, Inspector Clinton, Barry's nemesis, arrives on the scene. After the medical examiner declares that Mrs. Fleming's jugular vein was severed by a sharp instrument, an inventory of the crime scene reveals that the carving knife used in the photo shoot is missing. Under interrogation, Mac admits that he is on the verge of bankruptcy and that his wife Erika is Mrs. Fleming's niece, and consequently, the sole heir to the Fleming fortune. At that moment, Erika appears and identifies Madge as the divorced first Mrs. Fleming. Clinton then dispatches a detective to Madge's house to question her, but when he arrives, she is dead, an apparent suicide from an overdose of sleeping pills. When the missing carving knife is found among Madge's possessions, Clinton concludes that she murdered Mrs. Fleming and then committed suicide. Disputing Clinton's conclusion, Barry undertakes his own investigation and learns that Erika was planning to divorce Mac and had been romantically involved with both Fenley and Duerr. Deciding to pay a surprise visit to Julie, Barry discovers that she has suddenly left town without a forwarding address. That same night, Erika is found strangled to death, and Mac, who has no alibi, is taken into custody for the murder. Convinced of Mac's innocence, Barry continues his independent investigation. Deciding to employ a ruse, Barry confronts the last remaining suspects in the case, Kirk and Harry, and informs them that whoever hired Madge is the murderer. Just then Jane, whom Barry had asked to call the studio and pretend to be Julie, telephones. Because Kirk, who answers the phone, realizes that it is Jane, Barry is frustrated that his trick has not worked. Moments later, though, Harry answers the phone and tells Barry that it is a long-distance call from Julie. Suddenly trapped, Kirk, who is the murdered, draws a gun and is about to shoot Barry when Inspector Clinton and his men arrive, just in time to save him and arrest Kirk. When Jane arrives, she happily confesses that she also made the second call and convincingly imitated Julie's voice.