Italian writer and journalist Roberto Saviano reveals the inner workings and gruesome violence of South America's drug cartels, along with the global impact of the cocaine market.

Cocaine is more than just a drug.

With consistently high global demand and the potential for huge markups between production and distribution, cocaine forms one of the most lucrative markets in the world.

Roberto Saviano is an Italian writer and journalist whose book Gomorrah, detailing the crimes of the Neapolitan drug trafficking mafia, brought him both fame and death threats.

Now, Saviano goes back to the source of the drugs pushed by the Italian mafia, to the cartels of South America.

In ZeroZeroZero, Saviano finds an unspeakably violent and powerful criminal underworld that arguably isn't an underworld at all, but is linked to and sometimes even sanctioned by the same states that claim to fight it.