Ilha da Queimada Grande sits about ninety miles off the coast of Santos, Brazil, and holds the only wild population of the golden lancehead viper, roughly 2,000 snakes found nowhere else on Earth. VICE's Rocco Castoro and Jackson Fager join a Brazilian Navy crew on its annual maintenance run to the island's lighthouse, automated since the 1920s after the last keeper vanished while picking bananas, part of a local legend in which his rescue party died one by one searching for him. Walking the brush, researchers spot a viper every ten to fifteen minutes near the shore and as often as one every six square yards further in, snakes that feed on migrating birds in the treetops. The film also tracks the black market around the species, where smugglers known as biopirates can sell a single specimen for up to $30,000, driven partly by interest in the venom's potential medical uses. Access to the island is restricted by the Brazilian government, and the crew's own descriptions of the place, half awe and half warning, carry as much weight as the footage.