The Secret/Agent exists always in the silent, negative space of texts, practices, things, and discourse that focus attention on Security across the complex. This chapter examines some of the origins of the US government's attempt to fetishize secrecy on the US atomic complex. It also examines the ways material systems and nonhuman actors provide a framework for revisiting historical accounts in order to illuminate and make sense of such discursive practices. The chapter argues how secrecy itself functions as an agent, enabling discursive institutional practices that put communities at risk for decades in the name of security. It illustrates that posthuman theories can trouble and expands people traditional methodological approaches for studying historical accounts, bringing to light these discursive practices to provide not only a richer understanding of these complex research sites but also a space for addressing and irritating these practices.