During the regime of Manuel Odría (1948–56), state officials in the northern Peruvian Andes came to believe that their efforts to govern were being systematically thwarted by APRA, an outlawed political party forced underground by government repression. Officials concluded that the party had elaborated a subterranean political apparatus of remarkable scope and power, one that was largely invisible to the naked eye. I draw on officials’ fears of a dark and dangerous counterstate to cross-examine the literature on state formation. State theory has been predicated on the inevitability of state power, which makes it difficult to account for state crisis and also to grasp the highly contingent nature of successful efforts to rule. Much can be learned about state formation by examining moments in which political rule falters or fails, for it is then that the lineaments of power and control that otherwise remain masked become visible.