Armed with National Geographic's trademark inside access, takes viewers on a journey inside the most dangerous black markets on the planet. Each investigation in the eight-part series embeds with Peabody and duPont Award-winning journalist Mariana van Zeller as she explores the complex and often violent inner workings of a smuggling network. While she dives deeper and deeper into these underworlds, Mariana reveals - with characteristic boldness and empathy - that the people operating these trafficking rings are often a lot more like us than we realize.