Rio de Janeiro’s police officers habitually work on the edge of a border – between rationalised and ordered routines on one hand, and risk, disorder and incipient violence on the other. The article argues that this edge has distinct emotional components and concrete spatial consequences for the production of the city as a bordered space. Conceptually, the article combines spatial thinking about the production of territoriality with an emotional understanding of the police as ‘edgeworkers’ grounded in cultural criminology. Empirically, this piece uses ethnographic material from research with ordinary civil police officers and Special Forces in Rio. Across three empirical sections, the article explores police emotions and their significant spatial effects. First, the article mobilises the metaphor of ‘drying ice’ that police officers use to symbolise their everyday struggle with Rio’s urban conflict, and which leads them to produce spaces of secrecy. Second, the article shows how the police consider their job to be a vocation, a stance which simultaneously produces spaces of exposure. Finally, the Special Forces’ activities are compared to those of soldiers in war zones, assessing how the officers as edgeworkers find ways of escaping their emotional dilemma, thereby producing the city as a space of war.