Mariana immersed herself in the shadowy realm of international fraud, seeking to unravel its intricate workings.

Mariana delves into the complexities of fentanyl, a substance at the heart of the United States' most devastating drug crisis.

Mariana sought out those who crafted and traded the most skillful forgeries of American currency. She found them among artisans, quietly producing and offering their imitations to a select clientele.

Mariana seeks to unravel the complex motivations behind steroid use: the yearning for enhanced appearance, the underlying fragility of self-worth, and the insatiable hunger for more.

Mariana embarks on a quest to unravel the troubling reality of clandestine sexual encounters within the United States.

Mariana charts a course along one of the planet's most persistent smuggling trails, tracing the journey of cocaine from the Peruvian rainforests, across the Colombian coast, and ultimately to the avenues of Miami.

Mariana van Zeller ventures into the shadowy world of tiger trafficking, a clandestine and perilous realm from which few have dared to extract the grim realities.

Mariana's investigation reveals a clandestine network funneling weapons directly into the hands of powerful drug cartels.