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March of the Penguins (2005)
Can you ever see a penguin again without hearing Morgan Freeman's luscious voice in your head? But beyond its dulcet-toned talent, Luc Jacquet's innovative story of survival in the wild elevated its shuffling subjects beyond their own adorableness. They weren't just penguins. They were survivors. They were pragmatists. They were us — just marching on in the face of the constant obstacles of an inhospitable world.
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Long after the hippie attendees have passed on to that great mudfest in the sky, Michael Wadleigh's seminal — and superbly shot — rock doc will carry on the legend of the 1969 music festival's three-day revolution. Just as its subject changed music, Woodstock had an immutable effect on the documentary art form. It also happened to give a job to a young whippersnapper named Martin Scorsese, who would go on to make some of cinema's greatest films, both (concert and narrative).
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When We Were Kings (1996)
A passion project 22 years in the making, Leon Gast's exploration of the Rumble in the Jungle — Muhammad Ali and George Foreman's 1974 Zaire-based bout for the heavyweight title — paints The Greatest as a political genius, an underdog, a comeback kid, and an indisputable champion, both in and out of the ring. Colorful appearances by everyone from James Brown to Norman Mailer to Don King, plus a scintillating soundtrack, make the boxing pic a total knockout.
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Scared Straight! (1978)
Decades after its release, the shock doc about juvenile delinquents has become a punch line (and a recurring Saturday Night Live sketch), but it took major roots in American culture at the time of release as community Scared Straight programs began popping up like weeds. It also became the calling card of director Arnold Shapiro thanks to a sequel, 10- and 20-year follow-ups, and an ongoing A&E reality series, Beyond Scared Straight, launched in 2011.
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The Fog of War (2003)
Errol Morris's dialogic profile of controversial U.S. Secretary of Defense Robert McNamara — who served under John F. Kennedy and Lyndon B. Johnson as they formed Vietnam policy, and also had a decision-making role in the 1945 firebombing in Japan and the Cuban Missile Crisis — doubled as a searing indictment of another seemingly unwinnable conflict: George W. Bush's sprawling invasion of Iraq that was very much a part of viewers' everyday lives at the time of Fog's release. Its contemplation of the damning, deadly consequences of power struck a chord as another seemingly unwinnable conflict was a matter of contemporary national debate, and questioned the possibility of making the ''right'' choice in the midst of crisis.
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Harlan County, USA (1976)
From the hollers of Kentucky to Wall Street, Barbara Kopple and her crew spent years spent chronicling the events and aftermath of the bloody 1973-74 Brookside Strike, even placing themselves amid a hale of gunfire alongside the Kentucky coal miners who were fighting for their rights. Kopple's film also spotlighted the miners' wives, who were essential to the effort, providing a textured look at the toll of unfair employment practices. Jerry Johnson, one of the striking workers, even credited Kopple's film with his side's eventual victory.
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The Times of Harvey Milk (1984)
A historic account of a firebrand political figure, Rob Epstein's look at the slain San Francisco LGBT rights activist was the first film on gay issues to take home the Best Documentary Feature statuette. Seamlessly blending retrospective interviews, news footage, and archival footage, it presented a complex portrait of Milk that, in turn, inspired the 2009 Gus Van Sant feature, Milk. That film netted six Academy Award nominations and two wins, for Sean Penn's performance and Dustin Lance Black's script.
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Bowling for Columbine (2002)
Spurred by two teens' deadly shooting rampage at Columbine High School in 1999, Michael Moore's meditation on gun control was an over-the-top exposé about the perils of the Second Amendment. Marked by Moore's signature showmanship — a scene in which the director gets a free rifle as a perk for opening up a bank account, barbed montages set to the Beatles' ''Happiness Is a Warm Gun'' and Louis Armstrong's ''What a Wonderful World'' — the film drew criticism for Moore's blustery tactics and fast-and-loose fact presentation. Still, Columbine shattered documentary box-office records, its $58 million tally surpassed only by Moore's next project Fahrenheit 9/11.
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Hearts and Minds (1974)
With its ironic title (based on Lyndon B. Johnson's claim that the conflict's objective was winning ''the hearts and minds'' of the Vietnamese people), Peter Davis's narration-free anti-Vietnam piece showed that images are more powerful than words. The most striking, and controversial, of those images? The funeral of a Vietnamese soldier, whose family is overcome by grief, pointedly juxtaposed with an interview of General William Westmoreland claiming, ''The Oriental doesn't put the same high price on life as does a Westerner. Life is plentiful. Life is cheap in the Orient.''
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An Inconvenient Truth (2006)
Davis Guggenheim's cold, hard look at global warming could have been a snooze-inducing lecture; instead, it served as a wake-up call for environmental skeptics. With its urgent attitude toward a theory many widely dismissed, Truth was nothing less than scorching, transforming erstwhile VP Al Gore — not to mention PowerPoint — into a bona fide star.
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Common Threads: Stories from the Quilt (1989)
Much like The Times of Harvey Milk, Common Threads was a galvanizing force around an issue that many felt the Reagan administration had swept under the rug — or worse, persecuted. Confronting the tangible toll of the AIDS epidemic, Robert Epstein and Jeffrey Friedman's film took an important step toward representing HIV/AIDS beyond its association with the gay community by including profiles of a child hemophiliac, an IV drug user (though even one of its gay subjects, former Olympic athlete Dr. Tom Waddell, also broke stereotypes of AIDS ''victims''). Equal parts empathetic and outraging, the film remains one of documentary filmmaking's strongest calls to action.
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Inside Job (2010)
Charles Ferguson's dive into the United States' 2007-08 financial crisis plays like an apocalypse flick, only the Four Horsemen are wearing $10,000 suits. Using his academic background, Ferguson breaks down the intentional path of destruction financial power players paved for America, painting a picture of emotion and avarice for laymen who don't understand derivatives and deregulation. And his confrontation of well-compensated economists including Harvard's Martin Feldstein and Columbia University Business School dean Glenn Hubbard? Now that's a payoff.
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American Dream (1990)
Barbara Kopple once again examined workers' rights in a strike situation, this time finding a less black-and-white conclusion than she did in Harlan County, USA. Against the backdrop of the 1985-86 Hormel meat packers' strike in Austin, Minn., humanity shines on both sides of the picket line. The real villain? The titular ideal, no longer attainable in an economic climate growing more and more desperate by the day.