Ina Massine [Kathryn Grayson] is an opera diva who divorced throat specialist Dr. Lincoln I. Bartlett [Van Johnson] three years ago. Now she regrets this decision and does her best to win back his affection. Linc, however, is engaged to Agnes Oglethorpe Young [Paula Raymond], the daughter of his mentor, Dr. Carleton Radwin Young [Lewis Stone]. Nevertheless, Ina is determined to reconcile and grabs every chance to try to seduce him. Linc remains loyal to his fiancée, though, and soon grows irritated by Ina's attempts.
On the night of the premiere of her latest opera, La Bohème, Ina is troubled by a sore throat and calls Dr. Carleton Radwin Young [Lewis Stone]. Linc, who is substituting for Young that night, suspects Ina is faking. However, when he examines her, he diagnoses a tropical disease she had possibly gotten in South America.
Ina performs that night despite his diagnosis, and the next morning, after becoming upset with Linc and screaming at his portrait in her apartment, she is suddenly unable to speak. She goes to see Dr. Young, who diagnoses functional aphonia, a speaking disorder caused by shocking news. Young advises psychiatric help and tells Linc that a new love interest for Ina could solve the problem. Ina is assigned as Linc's client, much to Agnes [Paula Raymond]'s annoyance. Although Linc assures Agnes several times he has no feelings for Ina, the situation complicates their lives.
Linc contacts his brother, Chris Bartlett [Barry Sullivan], hoping he will be able to romance Ina. He sets up a date between the two, but Ina shows no interest in Chris and is only able to think of Linc. Later that night, Ina is able to break through Linc's wall of defense, convincing him to spend the evening with her. They enjoy drinks and dancing at a night club, where they are spotted by some of Agnes' friends. On their way back home, Ina again attempts to seduce him. Although Linc does not respond to her, he seems to have softened up.
A couple of nights later, with Ina staying in his apartment to take care of him, Linc, suffering from a severe cold, is bothered by a feverish nightmare. Linc wakes up screaming for Ina. When he wakes, he realizes he still has feelings for his ex-wife. He goes to the couch where she had been sleeping to hug her, and her voice suddenly returns. Just then, Agnes and Chris walk in on them. Agnes, feeling betrayed, breaks off the engagement despite Linc's attempts to explain. Ina announces that she too is fed up with the love triangle and storms out wearing Linc's pajamas. She soon returns, however, and is told by Chris that Linc is now suffering from functional aphonia. Ina figures out that this means Linc still loves her. She agrees to marry him again and they kiss, thus restoring his voice.
