A multiple murder involves peasants and Paraguayan government forces. Suddenly, a peasant testifies against his own side. He is an unnamed secret witness. Perla Álvarez sets out to look for him. However, this person becomes elusive and new questions arise in the process. Curiosity turns into an investigation and Perla wants to know who is behind the massacre. Far from finding any answers, she becomes trapped in the incongruities of the legal system, while the witness becomes a myth. Perla calls off the search with more doubts than when she started out, and while looking out on the extensive soybean fields she awaits for better times to come.