Several young music enthusiasts find a helpful supporter of their passion—singing and making music—in the endearing, friendly elderly gentleman Mr. Herzlieb, who works as a night watchman at a pawnshop specializing in musical instruments. Using a shortwave transmitter, they are even able to broadcast their pop songs all the way to Brazil, after which the music lovers are offered a gig. A German "Schlager-Film" (a musical comedy with popular songs).

Giorgia Moll
as Mary Miller

Jan Wennick
as Jan

Bubi Scholz
as Ralf Moebius

Kjeld Wennick
as Kjeld

Renate Holm
as Frau Renate Henkel

Rudolf Platte
as Herzlieb

Trude Herr
as Trude Pippes

Teddy Stauffer
as Robert Miller

Silvio Francesco
as Silvio

Rex Gildo
as Rex