This programme takes an unflinching, raw look at the origins and evolution of the most violent and dangerous gangs in the US. From humble beginnings by El Salvadorian refugees, MS-13 now terrorizes the streets of America, wielding machetes and brutality toward anyone who crosses them. We also uncover the criminal culture of motorcycle gangs such as Hell?s Angels, Mongols, and Outlaws. For decades, these clans have been linked to countless beatings, kidnappings, and murders, and today they are using the power of their image to spread their deadly message around the globe. Learn what life is like in their worlds, and observe law enforcement do their best to contain gangs in a deadly, ongoing game of cat and mouse.