This chapter sets out the book’s main claims and outlines its theoretical vocabulary. It explores why undersea cables have remained absent in media and communications studies and in public perception. Arguing that a new mode of visibility is needed for cable systems, the chapter delineates the key attributes of our global undersea networks: they are wired rather than wireless; semi-centralized, rather than distributed; territorially entrenched, rather than deterritorialized; precarious, rather than resilient; and rural and aquatic, rather than urban. A new historical approach, network archaeology, is introduced for the analysis of cable geographies. Using the Arctic Fibre cable project as a case study, the chapter introduces a number of critical concepts, including pressure points, turbulent ecologies, strategies of insulation and interconnection, and traction, to describe the spatial aspects of cable networks. Methodology is outlined and individual chapter descriptions are given.