Fishermen dying mysteriously off the coast of Japan. Entire populations of sea animals disappearing. Despite decades of work by the international community, the high seas remain law enforcement’s biggest blind spot, and the site of environmental crimes whose effects reach around the world. But some people are attempting to stop these crimes: We follow the investigations of two private-citizen sleuths, one using satellites to expose massive but previously untraceable illegal fleets, another using spycraft to infiltrate a criminal network of poachers and smugglers operating on both sides of the Pacific Ocean.

This episode features Sara Mitchell, professor of political science at the University of Iowa; as well as Jaeyoon Park of Global Fishing Watch and Andrea Crosta, founder and Executive Director of Earth League International.