Mara Salvatrucha, known as MS-13, began in the early 1980s in Los Angeles' Pico-Union neighborhood, formed by Salvadoran immigrants who fled their country's civil war and needed protection from the city's established Mexican and Black gangs. The film traces how that defensive posture curdled into one of the most violent criminal organizations in the Americas, marked by members who tattoo their bodies and faces and communicate through their own sign language. Deportation policy becomes a recurring culprit: high-ranking member Jose Abrego was deported four times, and each removal seeded new cliques back in Central America rather than shrinking the gang. By the 2009 National Gang Threat Assessment, MS-13 counted 30,000 to 50,000 members worldwide, with cliques from Los Angeles to the Washington D.C. suburbs to Toronto. The FBI's 2004 task force and ICE's Operation Community Shield, which racked up over 20,000 arrests by 2011, show law enforcement's response, while the gang's alliance with the Sinaloa Cartel against Los Zetas marks its move into transnational drug trafficking.