The film follows four families, with different nationalities (French, German, Russian and American) but with the same passion for music, from the 1930s to the 1960s. The various story lines cross each other time and again in different places and times, with their own theme scores that evolve as time passes. The main event in the film is the Second World War, which throws the stories of the four musical families together and mixes their fates. Although all characters are fictional, many of them are loosely based on historical musical icons (Édith Piaf, Josephine Baker, Herbert von Karajan, Glenn Miller, Rudolf Nureyev, etc.) The Boléro dance sequence at the end brings all the threads together.
Robert Hossein
as Simon Meyer / Robert Prat
Nicole Garcia
as Anne Meyer
Geraldine Chaplin
as Suzan / Sara Glenn
Daniel Olbrychski
as Karl Kremer
Jorge Donn
as Boris & Sergei Itovitch / Lead Dancer of Boléro
Rita Poelvoorde
as Tatiana & Tania Itovitch
Macha Méril
as Magda Kremer
Évelyne Bouix
as Evelyne / Edith
Francis Huster
as Francis
Raymond Pellegrin
as M. Raymond
Paul Préboist
as Le grand-père d'Edith
Jean-Claude Brialy
as Le directeur du Lido