A biopic of Vili Vesterinen, a popular Finnish accordion virtuoso (1907-61). After years of playing by the ear and for free at local country dances in his home province Karelia, he is accepted at the Viipuri Conservatory to study double bass. Accordion is frowned upon in classical music circles, and Vili is frustrated for having to learn to read music and pick up notes from his large 'cupboard', as he calls his assigned instrument. Depressed even more after his childhood sweetheart Mirja gets engaged to his best friend, he finally manages to join Dallapé, the most prestigious dance band of pre-war Finland.