How can crisis, breakdown, violence, and collapse be explained in the social sciences? This paper engages with this broad question by studying an extraordinary episode of mass tension and anxiety in postwar Sri Lanka caused by a mystery male predator known as the “grease devil.” Reports of widespread attacks on women in mid-2011 by this shadowy, ubiquitous, and powerful being led to heightened levels of vigilance and fear across large parts of rural and peri-urban Sri Lanka. It had a particularly strong impact on the formerly war-torn northeastern part of the island, where it led to violent confrontations between affected communities and the police and military. Drawing on primary research and by engaging with a range of literatures across the historical and social science literature, this paper attempts to reconstruct and understand the grease devil crisis. In doing so, it identifies and evaluates the different ways in which the crisis could be explained and the extent to which these approaches produce analytically relevant insights.