A young woman teaches commercial writing and makes her students practice by writing letters addressed to an imaginary recipient from Vienna. One day, the love letter the woman writes to this non-existent man is accidentally sent by one of her students –and falls into the hands of a real person.
Two young people fall in love and run away from home. They soon run out of money and he, who has a decent voice, finds work in a low-class variety show, where he is captivated by the charms of a dancer.
L'angelo del crepuscolo