For the background singers featured in 20 Feet from Stardom, music is a vocation. It is not merely an occupation or a pastime; it is a way of life, a “higher calling,” as the legendary Lisa Fischer would say. For 90 minutes, director Morgan Neville superbly maps out the development of back-up singing in the US throughout the decades, exploring its deep connection with African-American culture and women’s history. It’s fun to finally put names and faces on the oohs and aahs we hear on records aplenty, but the film always finds its grounding on the singers’ own unique voices, where its true soul lies.