They are a voice, but not usually a name. The role of the backup singer is explored in this fascinating new documentary by director Morgan Neville. In it, we have interviews with musical icons such as Sting, Mick Jagger and Bruce Springsteen, all of whom speak about the important role backup singers play in their music.

Some of the greatest ever songs are renowned for their backup singers, even if we don’t know the singers’ particular names. And what we learn from this documentary is that often they hold the key to a song’s greatness. The “Doo doo doo doo doo doo doo doo doo” in Lou Reed’s Walk on the Wild Side is just as critical as “Rape, murder, it’s just a shot away” is to Gimme Shelter. The voice is the purest form of music; it’s the most natural instrument in the world. Backup singers add colour and vitality to songs.

Twenty Feet from Stardom exposes a darker side to the lives of backup singers though. Any singer who wants to make it big on their own cannot remain a backup singer forever. The corporate nature of the business they work in demands perpetual youth and glamour. One USC Cultural Studies professor says Ike Turner treated his singers like “hoes.”

Aside from the problem of losing youth and glamour though, a greater one exists: you are owned by a business prepared to drop you or mistreat you at a second’s notice. The business also views your contribution as secondary. One Rock ‘n’ Roll Hall of Famer, Darlene Love, had to clean homes after being dropped mid-career.

Still, this is an uplifting documentary, with singers who have the voices of angels displaying their extraordinarily gifted talents to us. They prove just how critical they are to music. Culturally, we would be poorer without them.

Harry Wise