When Did The Long Island Serial Killer Last Attack? 'The Killing Season' Investigates The Disturbing Case

Documentarians Josh Zeman and Rachel Mills' interest in the unsolved Gilgo Beach murders inspired them to take a close look at the murders of sex workers whose bodies were discovered between December 2010 and April 2011. In their new series The Killing Season on A&E, the pair begins by investigating murders committed by the Long Island Serial Killer. As they strive to make connections between the victims, Zeman and Mills find themselves traveling all over the country, from Florida to New Jersey to New Mexico — and the series lays bare the hard truth that sex workers are at grave risk because they avoid law enforcement and often aren't considered truly "missing" until it's much too late. After police discovered the bodies of Maureen Brainard-Barnes, Melissa Barthelemy, Megan Waterman, and Amber Lynn Costello, it seems highly likely that the killer has chosen a new location to discard human remains but remains active. So, when was the last murder committed by the Long Island Serial Killer?

Much like the case itself, it's complicated and there are no clear answers. First of all, there's the very real possibility that more than one serial killer is targeting sex workers in New York. So, although we've dubbed him "the Long Island Serial Killer," it's poissble that more than one killer is out there committing these horrific crimes. In an interview with Bustle, Zeman says he was initially skeptical of the theory that more than one serial killer is at work — but his lengthy investigation for The Killing Season completely changed his mind:

"I remember hearing that there seemed to be an unsolved serial killer case, and I have to admit that I was shocked when I started to hear the rumors that it was two serial killers and not one — it sounded like some kind of bad Hollywood film. But after looking at the evidence, I now completely believe that there were two serial killers."
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Brainard-Barnes, Barthelemy, Waterman, and Costello weren't the only bodies found on Gilgo Beach. As Suffolk County District Attorney Thomas Spota said, "It is clear that the area in and around Gilgo Beach has been used to discard human remains for some period of time." These four women's bodies were wrapped in burlap sacks, but other sets of remains found on Gilgo Beach were not wrapped in burlap. Brainard-Barnes, Barthelemy, Waterman, and Costello were all identified as sex workers who used Craigslist, which is another indication that they were killed by the same person.

Additional bodies were discovered in the vicinity, but law enforcement emphasizes that it's possible these murders aren't the work of the same killer. Rather, a killer may have chosen the remote area of Gilgo Beach because they saw it as an ideal place to discard human remains without being spotted. Regardless of whether or not these individuals were killed by the same person, the last known victim of the Long Island Serial Killer is Costello, who disappeared on September 2, 2010 as reported by Newsweek. By the next day, her roommate Dave Schaller had a feeling something terrible had happened to her — the pair always kept in touch, and she even occasionally held dates at their residence so Schaller would be present in case anything turned violent. He was deeply concerned, but was told that he shouldn't worry because she'd turn up. Costello's body was discovered three months later in December 2010.

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Costello is the last known victim of the Long Island Serial Killer, but that doesn't mean he has stopped killing. In an interview with Bustle, Zeman speculates that he has perhaps moved on to a different place now that he's on the radar of New York law enforcement. However, there are multiple possibilities. "He's either moved on to a different place, he's in jail for something else, or he's dead," Zeman says. "It's also possible that something else has fulfilled his desire for killing."

It's entirely possible that the Long Island Serial Killer has found a new hunting ground and the missing women have not yet been discovered — as we see in The Killing Season, police seldom prioritize missing sex workers. But, let's pray that one of Zeman's other hypotheses is correct and no more women will be victimized by the Long Island Serial Killer.

Image: A&E