On August 12, 2017, white nationalists and neo-Nazis marched through Charlottesville, Virginia, chanting "Jews will not replace us," and the rally ended with a car driven into a crowd of counter-protesters, killing Heather Heyer. This Frontline and ProPublica investigation follows reporter A.C. Thompson as he works to identify the marchers from crowd-sourced photos and video, tracking individuals back to their jobs, hometowns, and online networks. Interviews with organizers, victims, and law enforcement officials examine why local and state police stood back as violence broke out in the streets, and internal planning documents and chat logs reveal how the rally's organizers coordinated in advance. The film traces the broader rise of organized hate groups in the years leading up to Charlottesville, using the event as a case study in how online radicalization moves into physical confrontation. It closes with questions about accountability, both for the individuals caught on camera and for the institutions that failed to stop them.