Taking off from the premise that French maps of the Sahara have long served as instruments of colonial violence, this paper seeks to explain why documentary film and photography have been among the instruments most capable of registering the enduring radioactive effects of the seventeen nuclear weapons detonated by the French military in the Algerian Sahara between 1960 and 1966. My focus is a small village called Mertoutek, whose residents were in the direct path of a radioactive cloud released during the subterranean detonation of a bomb named ‘Béryl’ at nearby In Ekker in 1962. One of the few existing documents of this disaster—and its enduring effects—is a film by Elisabeth Leuvrey called At(h)ome (2016), which is inspired by landscape photographs taken of the site by Bruno Hadjih. Leuvrey’s and Hadjih’s works combine image and sound to chart an invisible toxic territory of unknown, possibly infinite, scale. Authorized by secret clauses in the Evian accords and carried out at secret military bases hidden in the desert, tests like ‘Béryl’ were designed to be invisible except in carefully choreographed media propaganda events. Knowledge of this history has almost completely vanished from public record and collective memory, despite widespread international protest at the time—including 11 sessions of debate at the UN in 1959. At(h)ome, I argue, is an aesthetic cartography of a dangerous archival blank zone where old taboos on naming French colonial violence intersect with the present nuclear secrets of both the French and Algerian nation-states.