'Trafficked' probes dangerously deep into the criminal underworld

Dressed in a hazmat suit, journalist Mariana van Zeller and her film crew risk their lives observing a fentanyl "cook" mix the addictive and potentially lethal drug in an underground lab in Mexico.

The crew has been taken blindfolded to the lab, where the bulky cook tosses out the comment that his tachycardia (heart rate of over 100 beats) gives him an idea of how potent each batch will be.

In this episode of Trafficked, an eight-part National Geographic series on the drug underworld, Van Zeller is the first outsider to be allowed inside the fentanyl operations from the outset. Her crew films a "tourist" boat collecting 10 barrels of chemicals floating in the sea off Mazatlan port, Mexico.

Unsurprisingly, in a series probing dangerously deep into black markets and smuggling - drugs, tiger trafficking, gun running, counterfeiting, scams and pimping - subjects don't want their faces exposed.

"They don't want us to show their faces or anything, so we put our cameras down," she says when they're meeting members of a drug cartel pipeline on a street.

Von Zeller says that journalist Miguel Angel Vega played a critical role in building relationships with Mexican drug cartels to make this access possible.

Asked why they talk, he says: "It's always about ego because they want to show their muscle. They want to show their guns . Although they fear any of us could be undercover or informants for the DEA [US Drug Enforcement Administration]."

What makes the show stand out is not only the team's courage, but Van Zeller's talent at getting the criminals to open up.

Van Zeller, who's been reporting on the global underworld for 15 years, says: "People don't realise that black markets are all around us, hidden in plain sight. And what fascinates me most is how normal, law-abiding people - people like you and me - get pulled into these criminal worlds."

She also flags the fine line between what's legal or not, meeting with the Hulkish steroid king Dr Tony Huge while he is injecting his "guinea pigs" in the locker room of a gym with experimental body-building drugs.

"I'm feeling the pressure right now. I'm feeling really tiny and terrible," says Van Zeller, massively outranked in size.

But when it comes to figures at the top, like the pimps who are feted in movies, hit songs and bestsellers, there's another dynamic at play - that of cruel efficiency. One pimp in a balaclava tells her how he used a razor to cut the feet of a woman who tried to walk away from him. Then he tells her there are women much worse off in her home town of San Francisco, where she's filming the episode, rendezvousing in laundromat parking lots and on street corners. Pimping networks prove tougher for Van Zeller to infiltrate than gun-running networks.

Some of the figureheads associated with the "shadow economy" are already known to the public - like tiger breeder Joe Exotic, who's behind bars for murder-for-hire, and Doc Antle, charged with wildlife trafficking - both made famous by the Netflix series Tiger King: Murder, Mayhem and Madness.

The tiger breeding industry in the US, where there are an estimated 5,000 to 10,000 captive tiger cubs, fuels the deadly international tiger bones and parts trade, which Van Zeller follows to a casino in Laos.

Posing as tourists, the crew try to get shots of tigers in cages, which have been relocated, but they are forced to depart hastily.

Van Zeller also goes on an anti-poaching patrol in the forest. One of the scenes shows how people put their lives on the line, as Van Zeller and her crew do, to protect threatened wildlife and people.

Trafficked casts light on people behind the criminal curtain illegally working to meet the public's never-ending desire for riches, sex, guns and drugs. 

• 'Trafficked' premiers on the National Geographic channel on January 21.