Netflix’s new true crime drama, Lost Girls, tells the story of the hunt for the Long Island serial killer, who’s believed to have murdered at least 10 people and buried their bodies near a beach on Long Island, New York. The film doesn’t focus on the still-unknown killer or the official investigation into the killings, but on the grieving mothers and sisters turned victim advocates who pushed the police and media to take the murders of their loved ones seriously. At the heart of these efforts was Mari Gilbert (played in the movie by The Office’s Amy Ryan), who worked to bring attention to the the murder of her 24-year-old daughter, Shannan. Here’s what you should know.
Who was Mari Gilbert?
The book Lost Girls by journalist Robert Kolker served as the basis of the film, and in it Kolker offers details of Gilbert’s life that didn’t make it to the screen. She grew up in Lancaster, Pennsylvania, but moved with her three eldest daughters, Shannan, Sherre, and Sarra, to upstate New York to escape their heroin-addicted father. Gilbert worked a variety of jobs, including serving as a retail manager, teaching assistant, and Walmart employee, but continued to face personal struggles. Her next partner, the father of her youngest daughter, Stevie, was arrested for domestic violence, and her children spent nearly two years in foster care.
The girls eventually returned home, but Shannan would go on to spend more years in foster care. She was diagnosed as having bipolar disorder at 12 years old, and Mari struggled to manage her eldest child’s at times erratic behavior. Shannan also reportedly didn’t get along with her mother’s abusive boyfriend, further straining their relationship.
By 2010, Shannan was an aspiring actor who lived in Jersey City and worked as an escort. On May 1, she disappeared near Gilgo Beach after making a frantic phone call to police while seeing a customer. Though Shannan had been on the phone with 911 for more than 20 minutes and had been spotted running down the john’s quiet street knocking on doors and screaming for help, police did not arrive on the scene for almost an hour. It took authorities almost a month to connect the call to the missing persons report the Gilbert family had filed for Shannan. Mari Gilbert felt that Shannan’s disappearance wasn’t being treated with urgency, and that her daughter was being dismissed because she was a sex worker. “I think they look at them like they’re throwaway,” she told the New York Times in 2011.
She spoke to the press, putting pressure on police and ensuring that Shannan wouldn’t be forgotten. Seven months later, a police dog found skeletal remains on Gilgo Beach, leading to the discovery of three more bodies, all belonging to sex workers who’d used Craigslist to find their clients. Six more bodies would eventually be found. Shannan wasn’t among these victims, but the search for her had led to the realization that a serial killer was at work in the area.
Shannan’s body was found in a nearby marsh in 2011. Though county officials theorized that she had wandered into the marsh and drowned, an independent autopsy sought by Gilbert’s family found that Shannan may have been strangled to death. None of the murders have ever been solved.
“She was not perfect, but she was loved and she was cared for,” Gilbert told the press in 2011. “She does not deserve to be forgotten.”
How was Mari Gilbert killed?
Gilbert’s other daughters supported her effort to bring attention to their sister’s murder, and often appeared alongside their mother at memorials and when she spoke to reporters. But her third daughter, Sarra, suffered from severe mental illness. In his new afterward to Lost Girls, Kolker described the breakdown Sarra experienced after the discovery of her sister’s remains:
In late 2013, Sarra was watching the American Music Awards on television and became consumed with the belief that she and Shannan had cowritten several hit songs for Rihanna, Beyoncé, and Jay-Z. Not long after that, she developed a second, more ominous set of delusions, involving the people she loved becoming possessed by demons. She would insist that Shannan wasn’t dead, and that she could tell by looking into someone’s eyes if they were possessed. She told people she was a god, and her job was to defeat all evil gods, and that quite often the evil gods took the form of her sisters and mother.
Over the following three years, Sarra spent time in psychiatric hospitals and was diagnosed with schizophrenia. She drowned her pet dog, and lost custody of her son, who entered her mother’s care. On July 23, 2016, Sarra began hearing voices and called her mother for help. When Mari Gilbert arrived, Sarra stabbed her multiple times with a kitchen knife and beat her with a fire extinguisher. Despite her well-documented history of severe mental illness and the fact that Sarra had gone off of her medication before the murder, Sarra was found guilty of murder in 2017 and sentenced to 25 years imprisonment.
In describing Gilbert’s legacy, Kolker wrote that out of all of the family members of the Gilgo Beach murder victims, “Mari was the one who got the most out of the police, forced them to do things they otherwise wouldn’t. And she didn’t just make a lot of noise; the experience of fighting on behalf of her daughter Shannan transformed Mari, too.”