Hamburg in the summer of 2017, the top diplomats of the G20 countries are meeting in the port metropolis for a weekend in July. With his camera, photographer Markus Dorfmüller documents the work of the police and the state of emergency in society during these days. The new publication combines the resulting photographs with a selection of approximately 20,000 archived Twitter messages that refer to the official police hashtag #G20HAM17 and, in combination with the photographic images, describe the relationship of the city's inhabitants to the police. In his accompanying essay, Marinus Reuter discusses the close pact that the metropolis made with its police power at the time of industrialisation in order to be able to expand undisturbed. The picture that develops is of an urban landscape in which the whimsical rumours of social media become the precinct of modern police public relations, while a renaissance of the old protective police force takes hold on the streets.