The true story of the Long Island serial killer behind Netflix's new thriller, The Lost Girls.

In late December 2010, a cop was walking his dog along the marshy, windswept Gilgo Beach on New York’s Long Island, looking for a missing young woman, Shannan Gilbert. He found the body of a young woman wrapped in hessian. Only it wasn’t Gilbert.

“The first body we found we presumed was Shannan Gilbert,” police chief Stuart Cameron told People. “Then we found a second body, a third, a fourth… The shock set in.”

Police had stumbled across the work of a serial killer, soon dubbed the Long Island serial killer. The killings are the subject of new Netflix movie Lost Girls.

The four women were identified as Melissa Barthelemy, Maureen Brainard-Barnes, Megan Waterman and Amber Costello. All four women had been strangled and wrapped in hessian. They’d disappeared between 2007 and 2010.

Watch the trailer for Netflix’s new movie Lost Girls. Post continues below. 

Police kept searching. In early 2011, six more bodies were found nearby. One was a man wearing women’s clothes, who had been beaten. One was a female toddler. Three of the bodies had been dismembered. Four of them still haven’t been identified.

Finally, a year after the first body was discovered, police found the remains of Shannan, in a marsh near the beach.

So how could it have taken so long to discover a serial killer was at work?

Shannan had last been seen on May 1, 2010. She was a sex worker and had met a client through Craigslist. She was seen fleeing the client’s house, after calling 911 and yelling into the phone, “They’re trying to kill me!”

Her sister Sherre says she was last seen running along the roads.

“She felt like she was in fear for her life that night,” Sherre told 48 Hours. “She just disappeared into the night.”

The family struggled to get police to investigate Shannan’s disappearance because she was a sex worker. Her mother Mari refused to give up, continuing to hassle the police while holding down two jobs.

“I think they look at them like they’re throwaway,” Mari later told the New York Times. “They don’t care.”

The other four women were also sex workers. Their families had gone through similar struggles as they tried to get police to investigate.

“I contacted them,” Melissa Barthelemy’s family’s lawyer Steven Cohen told 48 Hours. “And they said, ‘She’s a hooker. She’s a prostitute. She’s an escort. We’re not going to assign a detective to this.”

Maureen Brainard-Barnes’s sister Melissa Cann told a similar story.

“The cop basically told us, ‘Maybe your sister just ran away. Maybe she doesn’t care about her kids…’” she said.

Even after all the bodies were discovered, including Shannan’s, Mari had to keep fighting. Police said they believed Shannan hadn’t been murdered but had died after staggering through the marsh while under the influence of drugs. Her family disagreed, saying an independent autopsy showed signs of strangulation.

“There is no evidence whatsoever that Shannan Gilbert died a natural death,” the family’s lawyer John Ray said.

Mari said she wouldn’t give up until her daughter’s killer was found.

“I hope it will bring awareness to any police department anywhere that regardless of who you are and what you do for a living that you are not judged, and that all cases are handled equally,” she told People.

So who was the killer? Clearly someone with a sadistic streak.

Days after Melissa Barthelemy had disappeared, on July 12, 2009, her younger sister Amanda had received a call from her mobile. It wasn’t from Melissa, but from a man who was tormenting Melissa. There were more calls, with the final one received on August 27.

“The last call he said he had killed her,” Barthelemy’s mother Lynn tells People.

Meanwhile, a friend of Maureen Brainard-Barnes, Sara Karnes, had received a similarly disturbing call just after her disappearance in 2007. It was from a man who “spoke properly” and described Maureen “to a T”.

In 2017, a carpenter called John Bittrolff was found guilty of killing two sex workers. The prosecutor suggested he may be responsible for at least some of the deaths attributed to the Long Island serial killer.

However, as yet, no one has been charged with any of the crimes.

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In January this year, on the day the trailer for Lost Girls was released, police put out a photo of a belt found at one of the crime scenes. It has the letters “WH” or “HM” on it, which police believe could be the killer’s initials.

“Why did it take nine years? I don’t know,” says Lost Girls director Liz Garbus. “But I’m glad that they’re putting new things out there and I hope they all continue to do so, so the families can get some resolution.”

Even if the killer is found now, it will be too late for Mari. One of her other daughters, Sarra, suffered a mental collapse. She was diagnosed with paranoid schizophrenia.

In 2016, Sarra stabbed Mari to death. She is now serving 25 years in jail.

The Lost Girls is now available to stream on Netflix. 

Feature Image: Netflix.