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 1980s. 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.
In Moscow, 1936, an aspiring dancer Tatiana marries a man, Boris, who will give her a son just before he is killed during World War II. In Berlin, Karl Kremer's success as a pianist is confirmed when he receives praise from Hitler – something which will haunt him throughout his life. In Paris, a young violinist Anne falls in love with a Jewish pianist, Simon Meyer; they marry and produce a son, but they end up on a train bound for a Nazi concentration camp. In New York, Jack Glenn is making his name with his popular jazz band. Twenty years on, their children are reliving their experiences, and Anne Meyer continues her hopeless quest to find the son she was forced to abandon.
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.
