Nighttime at the Kruger National Park uncovers a dark, secret, war between gamekeepers who protect and poachers who steal. Nelufar Hedayat investigates the black market, tracing the bloody path of rhino horn trade from Vietnamese dealers to South African smugglers.

Trafficked US weapons are fueling violent crime in El Salvador and Guatemala; riding through Central America's notorious ganglands, Nelufar Hedayat investigates how the guns get there, and who pays the ultimate price.