Starting in 2010, police searching for a missing woman found 10 sets of human remains in the scrub along a barrier island parkway, not far from the sands of New York’s remote Gilgo Beach. Police almost immediately feared some were left by a serial killer.

Over the years, investigators used DNA analysis and other clues to identify the victims. In some cases, they were able to connect them to remains found elsewhere on Long Island years earlier. Investigators concluded that an 11th person found dead — the initial subject of their missing persons search — accidentally drowned.