If you’re looking for a truly terrifying film to watch this Halloween, there’s no better choice than The Great Hack. 

Rather than haunted dolls or murderous Swedish cults, this Netflix documentary deals with a far more realistic source of terror: the idea that tech companies have become so powerful, they can manipulate us in ways we’re completely unaware of.

An in-depth look at Cambridge Analytica scandal

You’re probably vaguely familiar with the story of Cambridge Analytica, the Robert Mercer and Steve Bannon-connected tech company that imploded in early 2018 after a former employee claimed they had been using their technology to sway elections. 

But most people don’t know the details of the story. This is mainly because it played out in the news over a long period of time, involved a lot of different people in a lot of different countries, and, as it dealt with the manipulation of vast amounts of data, was hard to follow. 

The Great Hack does a good job of making the story engaging — and also possible to understand — in under two hours. 

The film tells the story by following three characters: Carole Cadwalladr, a journalist with the UK’s Observer newspaper who broke several of the stories that led to Cambridge Analytica’s downfall; David Carroll, a professor at New York’s Parsons School of Design who sued Cambridge Analytica in the UK in an effort to reclaim the data they’d gathered on him; and the film’s most fascinating character, Brittany Kaiser, a whistleblowing former Cambridge Analytica employee who we’re introduced to as she lounges, Bond villain-like, in a cliff-top infinity pool “somewhere in Thailand.”

Together they explain how the company was allegedly able to influence elections. In the case of the 2016 US presidential election, Cambridge Analytica did this by gathering huge amounts of personal data through Facebook.

That data came via a Facebook quiz app that launched in 2014.

The quiz was promoted as a fun way for users to find out more about the type of personality they have. The 270,000 people that used the app likely didn’t think too hard about the fact that the app’s terms and conditions allowed it to gather their personal information — and the personal information of everyone in their friends list. Cambridge Analytica claimed that, as a result of the app, it gathered 5,000 pieces of data on every single American voter.

Using this trove of information, they were able to identify a group of Facebook users they referred to as “persuadables” — undecided voters with easily swayable personalities. 

“We bombarded them with ads until they saw the world the way we wanted them to,” says Kaiser in the film, describing how Cambridge Analytica filled the persuadables’ feeds with pro-Trump, anti-Hillary content, some of which was fake news. 

At one point, the film features hidden camera footage of a Cambridge Analytica employee discussing a “Crooked Hillary” campaign they’d pushed on Facebook during the elections. “This stuff infiltrates the online community and expands but with no branding,” the employee says. “It’s unattributable, untrackable.”

It wasn’t just the US that was the target of Cambridge Analytica’s manipulation efforts. The film touches on a variety of campaigns in countries around the world.

In one particularly fiendish scheme, the company allegedly manipulated people in Trinidad and Tobago into not voting, using a fake grassroots campaign aimed at young black people, that encouraged them to abstain from the vote as some sort of anti-establishment statement.  

How effective was Cambridge Analytica? 

There is some dispute as to how powerful Cambridge Analytica actually was. Many believe that the founders were, like a lot of tech company owners, snake oil salesmen, who were overselling the power of their technology in order to make money. This film and other coverage of the company have been accused of being too paranoid in their treatment of the subject.

But, that's ultimately what makes this film so scary. 

Despite journalists and law enforcement agencies thoroughly investigating Cambridge Analytica, we still don’t know for sure what they actually did. For it to be even slightly plausible that a company could invisibly influence our behavior and, in turn, global politics, is terrifying. It would mean that reality, the most basic thing we have, might not even be the thing we think it is. 

What’s even scarier is that stories like this rarely change the way we treat our personal data. Through our phones and social media accounts, we continue to hand over massive amounts of our information to tech companies, no questions asked. 

“While we were being dazzled by what digital media could do for us, it was taking notes on everything we did, compiling a digital footprint that allowed us to be targeted by advertisers as well as political parties,” says David Carroll in the film. “We were so in love, no one read the terms and conditions.”

Regardless of how powerful Cambridge Analytica actually was, this film will hopefully make you stop and think about how your data is being gathered and used. At least until the credits start rolling and Netflix utilizes the personal data it’s gathered on you to autoplay another film it thinks you might like.