The Consensus Murders

Josh, a humor columnist for a city daily newspaper and his fiancé, Sally, become involved in the investigation of a series of assassinations that come to be called The Rooftop Murders. Well known citizens with obvious shady pasts, but who have never been convicted, become the victims. The same rifle is used in each case. The only clue is a 30/30 casing left behind at each crime scene - each one bares a message for the city. The authorities are baffled. Josh and Sally are up to the task.