After an impressive run of hit singles for Atlantic Records in the late 1960s and early 1970s, Aretha Franklin was in a position where she could creatively call the shots for her career. In January 1972, that found her wanting to return to her roots and record a gospel album.

She could have gone into any studio in the world and gathered any group of musicians that she wanted to, but she decided that a proper live recording in a church was the only way to go to capture the essence of the songs.

Warner Bros. decided they wanted to film the recording process, which was to occur over two nights at the New Temple Missionary Baptist Church in Los Angeles, for a feature-length documentary release. They brought in Sydney Pollack, whose 1969 film "They Shoot Horses, Don't They?" picked up nine Academy Award nominations, to direct.

Unfortunately, as the story goes, Pollack and his crew forgot to use clapper boards at the beginning of each take, which is what allows filmmakers to sync the sound recording to the film image and edit everything together. This massive error meant all of the footage captured sat in a vault for more than 40 years while the actual album went on to become the biggest selling gospel release of all time.

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With both Pollack and Franklin now dead and with the blessing of the singer's family, the languishing footage has been properly edited and constructed into the film it always should have been, thanks to advances in technology. The film, "Amazing Grace," screened March 16 at South by Southwest Film Festival.

The end result is simply astounding. Now credited as "Realized and Produced by" Alan Elliott (who was given all of the filming materials before Pollack died), it's a very warts-and-all presentation. There are moments that have focus issues, shots of people looking directly into the cameras and parts where crew members are visible. It's likely not the exact film that Pollack would have completed, but it stands as a remarkable document from the annals of music history.

Franklin, who would have been just shy of 30 when this was filmed, is clearly right at home with the Rev. James Cleveland, the Southern California Community Choir and her band members. After the first song, she heads to the pulpit to sing while the good pastor swaps places with her to take a seat at the Steinway piano to play. Her powerful voice resonates through the church, and the people gathered in the pews for those nights were treated to something special.

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Night one of the recording is definitely a little more subdued than night two and, in fact, you can tell that word spread about what was happening, because there are more people in the congregation for the second evening, including a visibly moved Mick Jagger.

This is a portrait of an artist at her peak and her most vulnerable, singing praise to the heavens. You don't have to be religious to be moved by the power of her voice and the honesty of her words. By the time the film gets to the showstopping title track, you will believe in the power of Miss Franklin, if not a higher power above.