Federico, his girlfriend Laura and her cousin, Caterina, are three young people full of hope, united by a great friendship that seems indissoluble. The three work in a department store but, when Caterina decides to attempt a musical career, given her vocal skills, everything changes. Caterina becomes a successful singer and Federico falls in love with her. Caterina, who however does not want to make her cousin Laura suffer, pretends not to reciprocate the young man by making him put his head in order. Meanwhile, the plots of various secondary characters evolve, in particular the fresh marriage between the security guard Antonio and the secretary of the department stores Adelina.