The Facebook/Cambridge Analytica case headlined technical news the whole Spring of 2018. This case is not the first (and certainly not the last) that demonstrates privacy issues with Facebook and the ecosystem around it; yet, it gained notoriety because of its scale and alleged direct effect on the outcome of the US presidential election. In this talk we look behind the scenes and under the hood and analyze the IT, economic, psychological and legal background necessary to understand the full impact of the Cambridge Analytica case. We touch upon the underlying economic theory on externalities that defines interdependent privacy and sets the scene at a high level; the permission system of the Facebook API that enabled the collection of personal data at scale; the breakthrough psychology research that enabled the use of these data to influence political elections; and the legal impact through the lens of the GDPR.