In Philadelphia, the soprano Prudence Budell returns from Europe after a period of five years training in the best Europeans music schools. Her millionaire grandmother Abigail Trent Budell sponsors an opera company under the command of the famous maestro Jose Iturbi to give a chance to Prudence to lead an opera. They hire the also famous tenor Guido Russino Betelli, but Prudence does not feel comfortable with him on the stage. When Prudence accidentally sees the American-Italian truck driver Johnny Donnetti singing opera, she convinces Jose Iturbi to give a chance to Johnny. They fall in love for each other, but when Prudence visits his work to tell that he will be hired, she meets Mary and she believes Johnny is in love of his colleague.