by the time they arrived, shannon gilbert had vanished. when the police came back later, they questioned the driver who took off after her. the driver told them that he brought shannon out from the city out to long island. police also questioned the man, according to the driver, was throwing the party when they left. that man was joseph brewer who did not return our phone calls to speak with us about this story. police told him gilbert wasn't just a party guest at brewer's house. >> brewer was the one that hired this young lady to come out here. >> shannon gilbert was an escort who posted ads on craigslist. because of her work as an escort, shannon's sisters sarah and sherry often worried about her. >> why did you guys come all of the way down here? >> because my sister disappeared. >> when did you first know that your sister had gone missing? >> we first found out that sunday, her boyfriend called me and said ha she hadn't come home in two days. >> did you have any thoughts? >> honestly i thought she ran off, found some friends and partie

he later learned the woman was 23-year-old shannon gilbert. i picked up the phone to call 911 and she bolted out the door. a car was going by, said they had a party around she got upset and left. he was looking to find her to bring her back to the party and he took after her. >> in the car? >> in the car. a that was the last time i saw her. >> reporter: clay says he waited 45 minutes for the police. by the time they arrived, shannon gilbert had vanished. the police questioned the driver. he told police he brought shannon from the city to long island. the man throwing the party was joseph brewer who did not return our phone calls to speak with us about this story. police told coletti gilbert wasn't just a party guest at brewer's house. >> brewer's the one that hired him to come out here. >> shannon gilbert was an escort to posted ads on craigslist. because of her work, shannon's sisters often worried about her. why did you guys come all the way down here? >> because my sister disappeared. >> when did you first know that your sister had gone mis

by the time they arrived, shannon gilbert had vanished. when police came back later, they questioned the driver would took off after her. the driver told him he brought shannon from the city out to long island. police also questioned the man who was throwing the party that shannon attended. that was joseph brewer, who did not return our phone calls to speak with us about this story. police told coletti gilbert wasn't just a party guest at brewer's house. >> brewer's the one that hired this young lady to come out here. >> shannon gilbert was an escort who posted ads on craigslist. because of her work astin escort, shannon's sisters often worried about her. why did you guys come all the way down here? >> because my sister disappeared. >> when did you first know that your sister had gone missing? >> we first found out that sunday. her boyfriend called me and said that she hadn't come home in two days. >> did you have any thoughts then? >> honestly, you know, i just thought maybe she found some friends, partied for two days and then she was go

. >>> this past december, police out searching for shannon gilbert in the area where she disappearedle on not one, but four badly decomposed bodies. >> okay, good morning, everybody. >> reporter: the police commissioner delivers news that terrifies shannon gilbert's family. >> i don't think it's a coincidence that four bodies ended up in this area. we could have a serial killer. >> reporter: four of the victims were found in a burlap-like material. that indicates two things. one, that it's very likely that those four victims were killed by the same person -- a serial killer. and the second thing is suggests is that the killer most likely killed his victims elsewhere and transported them here to be dumped. in january, police put names to the remains. shannon's family is relieved. she's not one of them. but they're still alarmed. all four victims are eerily similar to shannon in age, height and looks, and every single one advertised on craigslist as escorts. had police searched far enough? one of the bodies police identified was amber lynn costello. her sister, kim overstreet, is looki

shannon gilbert was not one of them. but like shannon, all the victims worked as online escorts.ng to meet clients. tim's 24-year-old daughter melissa was last seen in new york city more than a year and a half earlier. >> my fiance and i were actually watching, they were televising where they found the bodies, and we just looked at each other and we started crying, and we had a sinking feeling that it was her. >> reporter: now, it is one of the largest criminal investigations in long island's history. but when melissa bartholemie even the family's attorney, stephen cohen, could not get the nypd to take notice. >> i contacted them, 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. >> reporter: about a week after melissa disappeared, her 15-year-old sister amanda, shown from behind to protect her identity, got a call from melissa's phone. >> and 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. >> and this voice is saying, o