Silent Assassin

Jeremy Wade travels to the Paraná River in the remote northeast corner of Argentina to investigate the death of a young girl. Once there, he discovers a second death. The people who live along this river bank fear the creature they call "River Dog." This is a new species to Jeremy, a river monster that somehow got under his radar. His discovery is not only the most alien of all river monsters, it is also the largest totally freshwater river monster Jeremy ever has caught!