Bruce Sinofsky, co-director of the gut-wrenching Metallica documentary Some Kind of Monster, is dead at 58 from complications relating to diabetes. The band tweeted its condolences tonight, calling Sinofsky "a courageous man with deep empathy and wisdom who wasn't afraid to dig deep to tell the story."

Released in 2004, Some Kind of Monster traced Metallica's journey through one of their darkest periods, after bassist Jason Newsted left and frontman James Hetfield's demons finally forced him into rehab. Sinofsky first worked with Metallica in 1996, when the band contributed music to the score of his HBO documentary Paradise Lost: Child Murders at Robin Hood Hills.

Sinofsky's filmmaking partner Joe Berlinger, in a talk with Variety, praised Sinofsky's "unique combination of courage and empathy," adding that "the extraordinary adventures we had on the road and the deeply stimulating experiences we had in the editing room were life-changing for all of us who knew him thanks to his wisdom and fervor to change the world."

Sinofsky also directed Good Rockin’ Tonight: The Legacy of Sun Records for PBS, along with the 1998 TV special Where It's At: The Rolling Stone State of the Union, which featured Bruce Springsteen, Beck and others. Variety reports that a memorial service for Sinofsky will be held this March.

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