From the 1930s introduction of radio by settlers, to the clandestine broadcasts of guerrilla groups, to radio’s use in the Portuguese counterinsurgency strategy during the Cold War era and in developing the independent state’s national and regional voice, narrates a history of canny listeners, committed professionals, and dissenting political movements. All of these employed radio’s peculiarities—invisibility, ephemerality, and its material effects—to transgress social, political, “physical,” and intellectual borders. follows radio’s traces in film, literature, and music to illustrate how the technology’s sonic power—even when it made some listeners anxious and frightened—created and transformed the late colonial and independent Angolan soundscape.