A college professor turns songwriter and falls for his lyricist.

Professor Donald Hardwick, a solemn young music teacher, comes to New York to have his symphony published and to visit his wayward aunt Martha, who disgraced the family by falling in love with a saxophone player. At his aunt's house, he meets Linda McKay, a lyric writer, who senses the commercial possibilities in the professor's music. Teaming up with music publisher Ed Clark, Linda converts Donald's compositions to swing, and the duo swing their way up the Hit Parade, scandalizing Donald's classically trained aunts Annabella, Henrietta and Penelope, as well as the college music department and Donald himself. Their success attracts the attentions of Sam Hudson, a rival music publisher who wants the team for his firm. Also interested in their songs is Zelda Manion, a torch singer who wants to exploit the professor's musical talents for her own benefit. Zelda achieves her goal by feeding the professor a potent rum drink, which she identifies as lemonade. Thus ensnared by the power of alcohol, the songsmith earns a reputation as a wild and crazy guy, which brings his three aunts to New York to save him. After Hudson tricks a drunken Donald into signing a contract, Donald's new collaborator, Joe Dirk, exploits the professor's acclaim by plagiarizing a classical piece and signing Donald's name to it. For this act, Donald is brought to trial on charges of music pinching, but he is saved by his aunts, who argue that all composers have borrowed from each other, thus convincing the judge, who writes music himself, to throw the case out of court. Freed from both Hudson and Zelda, Donald returns to Linda, who has stood by him through his notoriety.