A look at the complex inner-workings of the global underworld, black and informal markets.

Mariana goes in search of the elusive chemists who make the world's LSD.

Mariana exposes the dangers of the growing and deadly ghost guns industry.

Mariana investigates how illicit oil is fueling terrorist groups worldwide.

Mariana explores surrogacy's dark side; a babies-for-cash black market.

Mariana investigates the lucrative black market for private data.

Mariana journeys into gangland to understand the violence plaguing LA.

Mariana embeds with crypto scammers who show her how they make millions.

Mariana investigates the growing popularity of bare-knuckle fighting.