"Things that wind up on the cutting room floor of everyone else's documentary become key pieces of this film," says Williams.
Kessler, who eventually moves in front of the camera during the film, thinks those scenes make the documentary more authentic.
"People know that the film is so honest," he says. "They know these moments are not set up in any way."
After working together on the film for more than two years, the two now share an obvious ease with one another. They're even looking for another project to collaborate on.
"We're married," says Williams, smiling. "We have the rest of our lives all mapped out."
Director Drew DeNicola never got the chance to bond so thoroughly with his principle subject. Big Star frontman Alex Chilton met with the documentary filmmakers, but didn't grant an on-screen interview before dying of a heart attack in 2010.
Chilton's death came shortly before a mostly reunited Big Star was to play SXSW. A tribute show was instead hastily assembled. That makes SXSW a very fitting place to screen "Nothing Can Hurt," which is showing as a nearly finished work-in-progress cut.
"Once Alex passed away, the interest in Alex's place in the pantheon was just so much greater than we knew," says DeNicola. "I think that pushed the film further."
The running narrative of the film is how commercial success eluded such an obviously exceptional band like Big Star, which in three albums created some of the finest pop songs of the 1970s. Though a wealth of today's bands cite Big Star as an influence and the group is often called the first alternative or indie band, many music listeners are only familiar with their "In the Street" because it was the theme to "That '70s Show."
"I started thinking about where Big Star lies in music history," says DeNicola. "They happened to sit in this horrible little pocket of time after Woodstock and before the punk revolution."
Follow Jake Coyle on Twitter at http://twitter.com/jake_coyle
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