Alex Gibney’s new documentary explores the future of cyber warfare – including a virus that can hack computers offline. But is it a worthwhile film? Nicholas Barber has a verdict.

In Alex Gibney’s new documentary, Zero Days, one interviewee recalls how he felt that he was living in a Bond movie, and you can see what he means. The film is a fast-moving, nerve-racking international thriller involving espionage, classified operations, sneak attacks on foreign nuclear facilities and the shadow of armageddon. All that’s lacking is a hero as reassuringly capable and honourable as James Bond.

Instead, Zero Days is reminiscent of that scene in Skyfall when Q tells 007 that he can do more damage with his laptop before his morning cup of Earl Grey than Bond can do in a year. Secret agents with guns and exploding pens are now the stuff of historical dramas, it seems. Today’s spycraft is all about malware and worms and Programmable Logic Controllers – so anyone seeing Zero Days should prepare for sheaves of techno-jargon. But Gibney, the director of Going Clear, We Steal Secrets and the Oscar-winning Taxi to the Dark Side, has once again taken a potentially bamboozling subject and arranged it into such a clear and compelling narrative that even an IT-ignoramus – me – can follow it.

It seemed to be able to hop into any computer in the world

As ever, Gibney is helped by an array of top-notch talking heads, the best of whom are two US-based cyber-security specialists, Eric Chien and Liam O’Murchu. In 2010, a client of theirs in Belarus asked them about a virus he had spotted on his computer. When they looked into it, they found that it was like nothing they had ever seen before. For starters, its purpose was a mystery. For another thing, it was far too sophisticated to have been designed by hacktivists or identity-thieves.

Catching the bug

It seemed to be able to hop into any computer in the world, even those which weren’t connected to the internet. Crucially, it contained several “zero day exploits” which meant (I think) that it could carry out its unknown mission without any warning or external triggering signal. Gibney has to rely on some traditional cyber-thriller visuals at this point – screens full of figures, bundles of cables, rows of flashing lights – but it’s still nail-biting stuff. And it gets even more tense when Chien and O’Murchu discover that the virus, which they name Stuxnet, is targeting a uranium enrichment plant in Iran. Surely, they reason, the US and Israeli governments must be behind it. But wouldn’t that make Stuxnet a weapon of war?

It is chilling to hear that computer viruses can now cause ‘real-world physical damage’

It wouldn’t be fair on Zero Days to say too much about where the trail leads next, even though most of the material in the film has already been made public. But Gibney does an exemplary job not just of spinning a detective yarn, but also of widening his scope to include global politics, US presidents from Nixon to Obama, and so many secret services that you’d need a computer to count them.

Unsurprisingly for a film about information technology, it doesn’t have the human element that makes Gibney’s best work so enthralling: the origins of Stuxnet are still so highly classified that none of its architects will talk about it. The film also loses some of its urgency in its last half-hour, as Chien and O’Murchu’s sleuthing gives way to academic discussions of the uncharted territory of cyber warfare. But it is still chilling to hear that computer viruses can now cause “real-world physical damage” on a scale that experts would have laughed off as ‘Hollywood-esque’ just a decade ago. And Gibney succeeds in letting viewers see how far-reaching the consequences of Stuxnet have been – and how far-reaching they could still be.

It’s enough to make you nostalgic for the time when a gun and an exploding pen were all you had to worry about.

★★★★☆

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