Był jazz (1984)

Original title: Był Jazz

Set in 1952, film tells the story of young musicians playing - then forbidden - jazz music in basements and attics around Poland. The group hires itself to social parties, youth dances, etc, each time waiting for the management to disappear in order to shift gears to hot music. The crowd either loves it or does not know what to do. Occasionally they are harassed by the police.