Mark Kermode neatly summarises the merits of the Oscar-wining doc:
Investigating the (mostly) unbridgeable gulf between the back and front of the stage, Morgan concludes that talent and stardom may not be intertwined, as each of his interviewees wrestles group dynamics and personal ambition. A sharply cut early montage neatly establishes gospel singing as the bedrock of the blues and beyond, with conversation often slipping spontaneously into song. Springsteen, Stevie Wonder, Bette Midler et al offer insight into the music business while Sting witters about “spirituality”, but it’s the likes of Darlene Love who are the real stars here.
Lisa Fischer was amazing too. This documentary really exceeded my expectations.