Investigative Journalist Mariana van Zeller Reacts to Intense Moments in the Field | Nat Geo

I'm Mariana Vanel, and this season of Traffic was a whirlwind. Oh, this is so crazy! Like 1, 2, 3, 4, 5, 6, 7, eight arm guys like walking right towards us. Join me on this incredible journey of unprecedented underworld access. How far up do you think the corruption actually goes in South Africa? I'm to the top level. We need to go; it's not safe here.

The episode about body parts for Season 4 of Traffic was really shocking. This is my pen, okay? And inside that pen is a slice of human brain. Yeah, that was a real reaction of shock. I'd actually spent time on the phone with this guy. He's a funeral director, and trying to convince him to go on camera. After a while, he agreed, and he shows up in his suits and he's super serious. He hadn't told us that he was bringing us a little surprise.

So, when he took out the fan, "Can I see it?" "Absolutely." So, this is a little piece of brain. Yes, it is a human brain. Yes, wow! Yeah, and where do you buy it from? Facebook or Instagram? It was, I think, one of the most shocking moments of Season 4. I'm not easily nervous or scared, and in this situation, I really was.

We interviewed an assassin about 15, 20 minutes from my home in Los Angeles, and this was a really unsettling moment. We're driving to meet the assassin, and my contact basically tells me he's just a little nervous and a little, uh, iffy about it. Is he nervous to the point that things can get ugly? Yes, it's unsafe for us.

Yes, 'cause he thought like it was a setup. Like, "If I set up, like I'm killing you and everybody." I remember stopping the car and turning to him and asking, "Wait, wait, wait, what's happening here? I think before we meet him, we should talk." So, he's for sure an assassin?

Oh, I've seen people pay $880,000 right in front of me for a hit. Yeah, I've seen it. To me, just like my ip Po, he just, he could be cool in a second. He just like, "Yeah, that's one crazy right there." And so, we got there, and he was, I mean, you could see he was in a bad mood.

"You guys better block out by covering you, everything, changing my voice to—we're changing your voice, so is the only chance you guys got. I can easily take your H you out right now." The whole time, I'm looking at the end of the road and thinking, "If a police car shows up, he's going to think it was because of us, and we are all dead." So, you know, I get a little bit nervous. So that's when my instincts started kicking in, you know, but that's just me.

So yeah, that was an interesting one. It's one of my favorite episodes of the season. Assassins, we spend months trying to gain access to illegal gambling dens. Finally, we got access to this high-rise in Downtown LA. Within like half an hour or something, we hear yelling from the room. They’re making a ton of [Music] money, and we know sometimes they turn dangerous, but we didn't realize actually how fast they turn dangerous.

"Tell you what, we doing? What we going to do? Understand what's up?" I promise you, you don't know. People start running out and leaving the apartment, and we're stuck in this little corner, and we just rolled with it and kept filming.

So, let's talk about the drama. What happened? I don't know anything. I don't know. But there was a gun and there was a knife. I don't know; I don't know about a gun and a knife. I don't know anything, okay? But it was a crazy moment, and it really showed that we were right to do the story.

This is actually one of the most beautiful places I've ever been to in my life. It's the DRC, the Democratic Republic of the Congo. Unfortunately, it's also torn apart by violence and poverty. Only 5% of the roads are actually paved, so for us to get to this park took us forever. We got stuck; we had, I think it was like six trucks, and we had an extra one in case we'd get stuck 'cause it's such a dangerous part of the country.

It's full of rebels that they say that if a car gets stuck, it's better to just leave it behind. After a long journey, we met with this tribe, and it's very much sort of the message of Traffic. Do you think that people who are killing chimpanzees and gorillas in the wild are horrible people, right? And that's certainly what I thought before going there.

We're not here to judge; we're just here to understand and ask questions. And then you meet people who are essentially dying because they don't have food on the table for themselves and their families, and they're desperate. [Music]

And somebody offers them $10, and that's enough in the Congo to feed their families for a week. $10. When you hear the baby crying and uh screaming and the mother coming, do you feel bad? Do you feel sad? They have no other way, and that's so many times that is the situation of the operators in these black markets.

It's a lack of opportunity that turns them into the black market. Let's not think in a monolithic way. Not every poacher does this because that's what they want to do, but there are those who are compelled to do it because of life's hardships.

I'm so proud of this show because it's completely devoted to these underworlds. It is really what I love to do; it is my passion. Curiosity about the world motivates me and a deep need to understand the darkest corners of the world.

No, you're going to see something that nobody can see. This place—it's not for everyone. Not for everyone. If you want to continue investigating with me, be sure to watch the newest episodes of Trafficked: Underworlds, now streaming on Hulu. [Music]