Who knew that beloved and ubiquitous pop songs had their own underdogs? '20 Feet From Stardom,' the preternaturally crowd-pleasing documentary that made its debut at this year's Sundance and is guaranteed for all sorts of awards recognition, shines the spotlight on the voices that have “ooh”-ed and “lah”-ed through the soundtrack of popular music. I wouldn't go overboard and call it a masterpiece, but for entertainment and “stand up and cheer” value, it's top of the charts.

Director Morgan Neville (of numerous 'American Masters' and 'Biography' entries) gives the star treatment to a select group of African-American women who appear on the hooks and melodies of all the tunes we sing in the shower. They are the hardworking backbone of classic tunes, and each, for whatever reason, never quite “made it” on their own.

Among them is Lisa Fischer, without question the most talented of the group. With an outstanding vocal range and a winning personality, she sang backup for Luther Vandross and continues to collaborate with the Rolling Stones and Sting. She even won a Grammy, yet only industry insiders know her name. Is she too nice for the cutthroat world of the music biz? Or is it just dumb luck?

It's a question that's brought up time and again with other talented women – from young Judith Hill (late of Michael Jackson's group) to Claudia Lennear, whose solo tracks from the 1970s are presented in this film as unearthed gold. They all have ample talent; they all made a play for the front of the stage; and they all, eventually, retreated to the back once they failed.

The story is a little different, however, for Darlene Love, whose story of exploitation at the hands of producer Phil Spector forms something of a spine for the picture. Before the age of 20, she was singing (and singing lead) on the classic “girl group” tracks of the 1960s, but her name was never released to the public. Her legal screwing got so bad that she spent years as a cleaning lady even though everyone in the world at one time or another hummed along to one of her songs. Her triumphant eventual return to the spotlight on her own terms (thanks to the David Letterman show and the closed NYC nightclub The Bottom Line) is the sweeping emotional turn that ensures this movie will be a word-of-mouth phenomenon.

The other big moments come from Merry Clayton, a former backup singer for Ray Charles (a Raylette) who has enough charisma for her own trilogy of movies. If you ever wondered who was singing alongside Mick Jagger on “Gimme Shelter,” now you know, and the isolated track of her vocal is one of the top goose-pimple moments of the year.

'20 Feet From Stardom' doesn't hesitate to dig in, a bit, into racial politics. Lou Reed's “Walk on the Wild Side” with its uncomfortable refrain, “And the colored girls go 'doo-de-doo-de-doo,'” is heard over the opening credits. African-American women have been doubly exploited throughout American history, and pop culture has been no different. And while even Darlene Love at age 70 seems a contented individual, there is a degree of bite to this film.

Even at just 90 minutes, '20 Feet From Stardom' does get a bit repetitive at times. (And, quite frankly, some of the '90s R&B stuff doesn't hold up quite so well.) The film is at its best when it tells its frank stories. In addition to the individual, striving women we meet are the more workmanlike Waters Family – a group of singers whose resume includes jingles, TV-show themes and even the whoops of the creatures in movie blockbusters like 'Avatar.' This is a film rich in pull-back-the-curtain moments; it's a must see for anyone interested in the crossroads between performing talent and business.

'20 Feet From Stardom' is now playing in select theaters. 

Jordan Hoffman is a writer, critic and lapsed filmmaker living in New York City. His work can also be seen on Film.com, Badass Digest and StarTrek.com.