This is the fifth in a series.

Memorial Day weekend 1969 at the Jersey Shore is remembered for more than great weather and sandy beaches. That year two college girls were found brutally stabbed to death just a few yards from milepost 31 on the Garden State Parkway and their abandoned car.

All leads seemed to go nowhere; a composite drawing of a suspect and a $20,000 reward didn’t produce an arrest. Pressure on the police led to frustration, which was reflected in a May 29, 1970 Associated Press article posted from Somers…