The film, directed by Laura Poitras, explores the life of the whistleblower whose revelations about the NSA sent shockwaves around the world

Laura Poitras’s film Citizenfour, looking at the exiled whistleblower Edward Snowden, has been nominated for the best documentary Oscar.

Poitras spent eight days with Snowden in Hong Kong as his revelations about the NSA were published in the Guardian, and instantly created a major diplomatic event. Along with input from Glenn Greenwald, the film also looks at the aftermath of the revelations, with Snowden moving to Russia while the US, having shown to be spying on its citizens on a vast scale, scrambled a response.

The film continues an arc for Poitras, who ended up on a US Homeland Security watchlist for her Iraq-based My Country, My Country, and who looked at the NSA’s spying in a 2012 film The Program with another whistleblower, William Binney.

With its incredible access and agenda-setting subject, Citizenfour could well consider itself the favourite in the category. It faces competition from Wim Wenders’ The Salt of the Earth, a biographical documentary looking at photographer Sebastião Salgado; the similarly minded Finding Vivian Maier, whose stunning street photography was discovered long after her death; Last Days in Vietnam, looking at the chaos of Saigon as the Americans departed following the war; and Virunga, a Netflix-produced doc exploring a national park in Congo under threat from militia.

There was no space, however, for the much-fancied Life Itself, a film about legendary US film critic Roger Ebert, who died of cancer in 2013. Given the Academy tends to love anything about show business itself, the team will likely be disappointed it didn’t get a nomination.

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