Girl told 'I'm watching your sister rot' on phone before cops' horrifying discovery

Gone Girls: The Long Island Serial Killer is now streaming on Netflix and below we look at the sping-chilling phone calls a teenage girl received from a mysterious man just days after her sister vanished

A teenage girl received disturbing calls from her missing sister’s phone before a horrific discovery was eventually made.

Amanda was just 15 when her older sibling, Melissa Barthelemy, 24, vanished without a trace. Melissa was from near Buffalo before she moved to New York City as a hairdresser after graduating beauty school.

However, unbeknown to her loved ones, Melissa found herself working as an escort, and in July 2009, she stopped making contact with her family.

Her mum, Lynn Barthelemy, later said: “Did she get hurt? We pull out the phone book, we get on the internet. We start calling hospitals.”

She also said she contacted NYPD to make a missing persons report, but claims she was dismissed.

However, a week later, Amanda started to get disturbing phone calls from Melissa’s device. Their mum recalled: “When Amanda answered the phone, you know, she was so excited. ‘Oh my God, Melissa’s finally calling me.’ And then, there’s a guy on the other end.”

Amanda confirmed she was “relieved” when her sister’s name popped up on her screen before things took a dark turn.

Lynn explained: “He was softly spoken and had a very controlled and comfortable manner of speech, which made his horrific messages all the more devastating… he began to toy with her… And for the first time, she heard the voice of the killer.”

One call involved the mysterious person claiming to be from the NYPD while in others he “said some pretty horrible things to Amanda”.

The mum said this included “sexually explicit” words about what he “was going to do to Melissa” while taunting her sister.

After the third call, police began tapping the phone to track down locations like in Manhattan, the Empire State Building and Times Square.

In one chilling call, he told Amanda: “I’m watching your sister rot.”

Grim Discovery

Over a year later, in December 2010, Melissa’s body, along with the skeletons of three other women, were found bound and wrapped in sacks. They were discovered off the highway near Gilgo Beach in Long Island. The grim finding came just two days after police found a body in a sack with her wrists bound in the same area.

The four women were eventually identified as Melissa Barthelemy, Megan Waterman, Amber Costello and Maureen Brainard-Barnes. They were all in their 20s and working as escorts and it became clear that a serial killer may be on the loose.

Suffolk County police meanwhile later told 48 Hours they believed the person calling Melissa’s sister was in fact her killer.

Gone Girls: The Long Island Serial Killer

Netflix just dropped a true crime documentary about the case with fans claiming they “couldn’t look away” from the gut-wrenching series.

It examines 11 murders that happened between 1993 and 2011 in New York state, including the women mentioned above.

The devastating episodes feature family members and law enforcement officials who speak about the missing sex workers and how they were overlooked until Melissa and the other women who were found at Gilgo Beach in 2010.

Despite the bodies being found 15 years ago, there wasn’t a significant breakthrough until two years ago, when police revealed their primary suspect as New York architect Rex Heuermann.

A DNA breakthrough matched him to some of the victims and was arrested in July 2023.

Heuermann, who is married with kids, has currently been charged with seven murders, and a trial date has not yet been set.

Gone Girls: The Long Island Serial Killer is available to stream on Netflix.