This photo taken on April 7, 2016, in Munich, at the office of the German daily 'Sueddeutsche Zeitung' shows several issues of the newspaper, titling the so-called 'Panama Papers'. AFP When John Doe, the anonymous whistleblower behind the Panama Papers, approached us, he handed us an opportunity. When the resulting investigation into the offshore finance industry was published on April 3, 2016, the world was handed a test. As investigative journalists, we seized the opportunity.