Riddle of the Golden River. Inspector Winwood Mysteries, #12

On his return from holiday DCI Steve Winwood finds he has three recent murders on his doorstep. The only connection is the method of the killings; a heavy blow to the head and then a sharp blade through the heart. Then there is the problem of his nemesis, Chief Superintendent Diane Bliss who has little time for his attitude towards modern policing. He is called to see Chief Constable Mchael Chapman who wants him to investigate a fraud.
The only clue he is given is a short riddle: 'If you want to know the secret of the golden river, look no further than Aberto Pereira'. Steve argues that this is a case for the Fraud Squad but Chapman insists inferring that those caught up in a financial scam are high ranking police officers as well as politicians and footballers. But why is this all centred on a sleepy town like Rutherford. Because says Chapman Steve knows Rutherford better than anyone else.
It takes old fashioned police work and the skills of his Sergeant Miles Davis with spreadsheets and financial products to solve the murders and the fraud which become intrinsically wound together. A short story that brings Winwood to contemplate retirement. Again.