Film director and producer Gabriela Cowperthwaite did not set out to make a film that would force a national moral reckoning over how we keep whales in captivity, slash the profits of Sea World, and make her the unexpected enemy number one of a multi-billion dollar industry. But that’s what happened. Her acclaimed film Blackfish tells the thrilling and heartbreaking story of Tilikum, an orca whale who killed three people while in captivity. Shot on a budget of just $76,000 and released in 2010, Blackfish has been viewed by more than 60 million people and has become one of the most impactful documentary films of all time. In the six years since its release, Sea World has ended its orca breeding program and pledged to phase out orca shows all together by the end of 2019. We speak with Gabriela about the making of Blackfish, the hazards of keeping cetaceans captive, and how her film catapulted her to the frontier of marine animal activism.