Metaphorically titled, The End of the Amazonia is focusing specifically on the mouth of the river in the lower Amazon, where it empties into the Atlantic Ocean. Coverage begins on the fishing communities that are the dominant industry in the region - over 60% of GDP here is in some way related to fishing - and the vast marshlands that are peppered throughout the waters it takes place in, which collectively make up a land mass larger than some European nations (Denmark, Sweden, or Belgium).
Various forms of wildlife are chronicled as they work their way into an estuary where skilled laborers bury their arms to the shoulder in the mud of mangrove swamps in pursuit of a crawfish that is considered by many to be a delicacy. The hunters are so good at what they do, they are able to determine whether the specimen in their grasp, still unseen deep in the mud, is a male or female - they do not capture females, leaving them in place so they can continue to breed and maintain the population that facilitates their livelihood.
Because of the overlap of fresh and salt waters that occur where the river meets the ocean, odd zoological phenomenon are often recorded in the area - such as white sharks being found up river, and ocean dolphins beaching themselves on riverbanks miles from their native ocean waters. The beaches here lead to the presentation of a theory Amazonian natives from the area as far back as twelve thousand years ago may have invented the original bathing suit - clay-fiber "tangas" that covered the same genitalia area that modern-day bikini bottoms cover on women.
Being the final episode of a series on the river as a whole, the third act of the film is dedicated to behind the scenes experiences the crew had - many positive, some terrible. Some of the practices and tactics the crew concocted in order to capture hours and hours of footage are highlighted, as well as some of the troubled people and causes the group was able to aid in their time spent there.