Al Jazeera’s Investigative Unit goes undercover to expose the criminal networks that control Africa’s gold trade. In episode 2 of its documentary series Gold Mafia, the media house reveals how illicit cigarettes are used to fund a massive money laundering scheme involving Zimbabwean gold.

The undercover reporters pretend to be criminals with over a billion dollars of dirty money that needs to be cleaned. They infiltrate rival gold gangs and meet South Africa’s most notorious money launderer, known as Mo Dollars. The investigation shows how he uses a complex network of shell companies and fake invoices to hide his illegal activities.

The confidential documents obtained by the investigators reveal the scale and sophistication of the money laundering operation, which involves politicians and bankers in southern Africa. The investigation also shows how the global demand for gold fuels a shadow economy that often operates with the collusion of financial institutions, regulators and governments.

Gold Mafia is a four-part series that exposes the corruption and plunder in Zimbabwe’s mining sector. The first episode, which aired on March 23, was praised for its ‘explosive’, ‘extraordinary’ and ‘amazing’ reporting.

Episode 2, Smoke & Mirrors, was released March 30. The remaining episodes will be available on April 6 and 13.