Having your name written on a coffee cup is now a normality. It’s something to make your order feel personal. But what if a coffee shop wrote more than that? If, in the time it takes to make a coffee, they found out everything about you from what you share online and added it to your coffee cup?

We took a normal, busy coffee shop in London and did exactly that. Young adults were offered a free coffee if they liked the cafe’s Facebook page, a completely normal offer in 2016. Their ‘Like’ and profile were fed to a team of researchers, who searched social networks and the web for details the customer had made public. That data was fed to a barista in the cafe, who wrote the information onto the customer’s coffee cup. Hidden cameras captured customers reacting to their identity out in the open.

The stunt takes place at a busy coffee shop in London, a coffee shop popular with young adults. Signs and staff promote the “Like us for a free coffee” offer outside of the cafe. The second a “Like” pops up, it is tracked by the research team, who hide in a van outside. Researchers have a rough time of 3 minutes to find as much as possible about the person by what they share. In those 3 minutes, the customer presents their “Like” to the barista and orders their coffee. Their data is then radioed from the researchers to the barista, wrote on the cup and served.

The online film documenting the stunt was immediately picked up and shared by major UK banks, financial services and even police forces. HSBC, Lloyds, RBS, Crimestoppers and The Metropolitan Police, to name a few. Overall, 2.5 million people viewed the stunt. UK media channels, like BBC Radio, The Independent and Sky News, spread the film and started a nationwide conversation on how to tackle identity fraud.

On the day of the stunt, behaviour change in our coffee shop customers was evident. Their initial reactions were, of course, of shock, which you’ll see in the film. Post-stunt behaviour went as far as all customers immediately updating their privacy settings on Facebook and other platforms.