During Stalin's Great Terror, more than a million Soviet citizens were arrested or killed for political crimes they did not commit. Who carried out these purges, and what motivated them? Alexander Vatlin opens up the world of the Soviet perpetrators using detailed evidence from one Moscow suburb. Spurred by ambition or fear, local secret police rushed to fulfill quotas for arresting "enemies of the people"—even when it meant fabricating evidence. Vatlin confronts head-on issues of historical agency and moral responsibility in Stalin-era crimes.