Maria Kaika’s City of Flows challenges the modern belief that nature, the city, and the home are separate domains. Through the case of urban water, she argues that the modern metropolis is not detached from nature but produced through the continuous urbanization of nature. Modernity’s Promethean project sought to tame rivers, droughts, disease, and environmental uncertainty through dams, reservoirs, pipes, sewers, and domestic technologies, thereby making cities appear autonomous from natural processes. Yet this autonomy is illusory: the modern home’s simple act of turning on a tap depends on vast hidden networks of labour, capital investment, engineering, political authority, and ecological transformation. Kaika’s central case studies are Athens and London, whose water histories show three phases of modernization: early attempts to discipline dangerous urban nature, the heroic infrastructural era that celebrated technological mastery, and the late twentieth-century crisis in which “tamed” nature reappears as scarcity, drought, privatization, and environmental risk. The work therefore exposes modern infrastructure as both material and ideological: it delivers comfort while concealing the socio-natural relations that make comfort possible. Kaika concludes that cities and nature must be understood not as opposites but as hybrid processes, woven together through flows that are simultaneously ecological, political, technological, and economic.