A film about Marcel Cellier who discovered for the world „Le Mystѓre des Voix Bulgares“, and their true cinematic story. For more than 50 years the swiss musicologist and researcher Marcel Cellier has been travelling beyond the Iron Curtain, collecting the best of the authentic folklore music of Eastern Europe. Following his steps, the film “travels“ around Romania and Bulgaria of today, revealing the secrets of the legendary Bulgarian choir “Le Mystѓre des Voix Bulgares“, winner of the most prestigious Grammy music award, as well as of the famous Romanian musician Gheorghe Zamfir.