Commissario Soneri, a detective from Parma, investigates an unsolved case of an unidentified dead body found in the Po River three years ago. To close the case, Soneri needs to look a little further. He can't however endure burying a person without a name, so he decides to reopen the case. The investigation leads him to river life, where he tries to break the wall of silence, typical of small communities harbouring poachers, petty criminals and big time profiteers.