Like a Hollywood action movie, the award-winning documentary Sea of Shadows (https://www.nationalgeographic.com/films/sea-of-shadows/en/#/) starts with a chase: not cars racing through the streets of a US city, but boats flying across the Sea of Cortez as the Mexican navy pursues poachers at night.

What you see is real, yet the suspense and unexpected twists in the story – about saving a nearly extinct species of porpoise, the vaquita, and exposing the criminal syndicates responsible for the slaughter – are as gripping as if they had been scripted.

Andrea Crosta, co-founder of Earth League International, (https://earthleagueinternational.org/) who investigates and exposes wildlife criminals, says: “We are always looking for situations like this one, where everyone thinks it is an environmental problem but in fact it is a crime problem.”..