The City Musick and renowned vocal ensemble I Fagiolini collaborate in the first of a series of recordings of music by Orazio Benevoli and his contemporaries in seventeenth-century Rome, the focal work being a world premiere of Benevoli's Missa Tu es Petrus. The Roman musical style featured many large scale works of the 'Colossal Baroque' - multiple choirs with voices and instruments, often employing a curious technique called 'reining in the donkey' in which lower parts move hastily underneath a static soprano line, supposedly rather like a priest perched on, and trying to hold back, a frenetic donkey.