Heavenly Voices tells the story of the castrato phenomenon, and how the most gifted amongst these singers rose to international stardom. Max Emanuel Cencic and Philippe Jaroussky, two of today's singing stars, take us back in time and talk about operatic entertainment in the Baroque Age. This is illustrated by paintings and prints from the time as well as major performances of today. In this film, many countertenors are featured in famous roles and in interviews, amongst them Jochen Kowalski, Andreas Scholl, David Daniels, Daniel Behle and Valer Barna-Sabadus.