Sigurdur Thordarson makes his debut as a computer hacker at the age of 12, hacking his school’s website. At 14, Siggi leaks documents to Icelandic media and exposes corruption in the Icelandic banking sector, which becomes front-page news. Siggi is revealed as the source and becomes known as the ‘teenage whistleblower’. In 2010, Siggi’s reputation brings him into contact with WikiLeaks founder Julian Assange. Siggi becomes an integral part of WikiLeaks and Assange treats him like his own son. They travel the world, leaking secret documents to the media while the US government looks on in frustration. But eventually he clashes with the increasingly manic Assange, who turns against him – and at 18, Siggi makes a drastic decision that will change his life forever.