Shortly before the War, Jan Lazlo, a Hungarian musician who has emigrated to France, falls for a young woman. Alas, the lady forsakes him and the poor man tries to overcome his grief by writing "Gloomy Sunday", a song so desperate that it can drive its listeners to suicide. Max, a music publisher, likes the song and decides to launch it by all means, foul or fair. Bob, his accomplice, manages to talk his mistress Michèle into committing a fake suicide. She obeys him and the scheme is a success a...