Mick Jagger, Bruce Springsteen, Sting and Stevie Wonder are all interviewed in Twenty Feet From Stardom, a documentary film about backup singers. After premiering at this year's Sundance Film Festival, it will have two screenings this week at South by Southwest in Austin, Texas and will open in select cities on June 14th. Darlene Love, Merry Clayton, Lisa Fischer, Tata Vega, Judith Hill, Claudia Lennear, Gloria Jones and Dr. Mable John are among the singers spotlighted in the movie. All have recorded under their own names, but are equally, or better, known for singing behind others.