This essay examines scholarship on the demonology of the Dead Sea Scrolls (DSS). It places a special focus on how the notions of evil spirits found in the Book of Watchers (1 Enoch 1–36) were adopted, adapted, and reconfigured in various ways in the scrolls. Concepts crucial to many groups within Second Temple Judaism (impurity, dualism, apocalypticism, and monotheism) functioned to influence how the evolving concept of demonic beings was received and deployed in Hellenistic Jewish thought. The DSS provide the largest and most significant data set for analyzing these developments. The essay concludes by suggesting a critical methodological issue for future research on Jewish demonology.