Twitter. Facebook. Whatsapp. Google Maps. Every day you share everything about yourself - where you go, what you eat, what you buy, what you think - online. Sometimes you do it on purpose. Usually you do it without even realizing it. At the end of the day, everything from your shoe-size to your credit limit is out there. Your greatest joys, your darkest moments. Your deepest secrets.

If someone wants to know everything about you, all they have to do is look.

But what happens when someone starts spilling state secrets? For politician Bethany Lehrer and programmer Danielle Farr, that's not just an interesting thought-experiment. An online celebrity called sic_girl has started telling the world too much about Bethany and Dani, from their jobs and lives to their most intimate secrets. There's just one problem: sic_girl doesn't exist. She's an construct, a program used to test code. Now Dani and Bethany must race against the clock to find out who's controlling sic_girl and why... before she destroys the privacy of everyone in the UK.