Some of the world's most dangerous places are not declared warzones, but regions where drug trafficking, ethnic tension, poverty, gang violence and political corruption have combined to create the most violent hotspots on Earth. In these areas, the situation is often so volatile that major news organizations have fled. Only a handful of photojournalists remain, armed with just their cameras, to document the horrors and attempt to make sense of the conflicts. Witness, follows three combat photographers into conflict zones in Mexico, Libya, South Sudan and Brazil. In following these photojournalists, Witness shows how, even when everyone else seeks cover, the war photographer stands.