In 2010, Gabriela Cowperthwaite read a news article that changed her life. It described how an orca whale had killed a trainer during a show at SeaWorld in Orlando. Cowperthwaite, a Los Angeles filmmaker who liked taking her twins to see orcas at the San Diego SeaWorld, spent the next two years making an investigative documentary, Blackfish, which depicted how the theme parks’ treatment of orcas harmed both the animals and their human trainers. The film cost just $76,000 to produce. Yet it quickly went viral, capturing the attention of celebrities and animal rights groups. Public pressure on SeaWorld mounted. Corporations cut sponsorship ties, regulators opened investigations into the parks’ safety practices, and lawmakers proposed a ban on breeding orcas in captivity. Eighteen months after the release of Blackfish, SeaWorld’s stock price had plunged 60%, and CEO Jim Atchison announced that he was resigning. By 2018, SeaWorld’s stock still had not recovered—all because one woman had read a story about orcas and made a low-budget film.