A phantom persona of LISK – Long Island Serial Killer – was created after law enforcement found the remains of 10 victims along New York's Gilgo Beach in 2010 and 2011.
For the next 12-plus years, LISK's persona become more sinister. Theories turned into conspiratorial ghost stories, and LISK became a boogeyman who could be hunting anywhere.
Little did anyone know, LISK is allegedly Rex Heuermann, a married father of two living about 16 miles from his alleged dumping ground among a neighborhood with current and former cops. The 59-year-old commuted to Manhattan, where he worked as an architect.
But that's actually the norm for serial killers, according to a 2005 FBI report, which noted that many live "boring" lives on the surface.
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"The majority of serial killers are not reclusive, social misfits who live alone. They are not monsters and may not appear strange," the FBI report says. "Many serial killers hide in plain sight within their communities.
"Serial murderers often have families and homes, are gainfully employed and appear to be normal members of the community. Because many serial murderers can blend in so effortlessly, they are oftentimes overlooked by law enforcement and the public."
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The phrase some experts use is "extraordinarily ordinary," which describes these three notorious serial killers' lives before they were convicted murderers.
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Dennis Rader preyed on victims in and around Wichita, Kansas, where he brutally killed 10 people from 1974 to 1977 and taunted news outlets and the police with letters and phone calls.
Known as "BTK" – bind, torture, kill – the U.S. Air Force veteran was a married father of two who worked in code enforcement and remained on the loose until his arrest in 2005.
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His daughter, Kerri Rawson, said she and her family were "completely blindsided."
"They were looking for him for 41 years, and I didn't even know what BTK was, that acronym, until 2004, when my dad came back into the media to play games," Rawson told Fox News Digital. "My dad would go murder somebody and then come over to dinner with a family."
Before his arrest, Rader was just her dad. He gardened, camped, hiked, fished and went to church. There are pictures of him with Rawson when she was a young girl, fishing and holding her on his shoulder, so she could top the Christmas tree with a star.
"He was this community leader, church leader, Boy Scout leader. And then there's the after, after he was arrested," Rawson said. "I know, on the outside, people are still like, ‘How do these guys have families?’ But you see it over and over, right?"
Rader was specifically mentioned in the FBI report as an example of a serial killer who was an upstanding member of his community and lived a "normal" life as a married father of two.
John Wayne Gacy is one of the most notorious serial killers in history.
He killed at least 33 teenage boys and young men in Cook County, Illinois, in the 1970s, and buried most of his victims under his house.
Before he was the "Killer Clown," Gacy was a building constructor in Chicago and a neighborhood hit as "Pogo the Clown," which was his character that he used to perform at kids' parties and charity shows for sick children.
He was a married man and considered to be a respectable businessman who was involved with politics. He was known for having his photo taken with then-first lady Rosalynn Carter.
During that time, though, he was raping and killing young men. He targeted runaways, recently released jailbirds or male prostitutes.
His murder spree came to an end when he was arrested in December 1978.
Joseph DeAngelo's first crime is believed to be a break-in rape in the Sacramento suburb of Rancho Cordova, California, on June 18, 1976.
Known as the "Golden State Killer" and "East Area Rapist," he was linked to nearly 40 attacks in the Sacramento and Stockton areas. He stalked his victims for days, breaking into their homes to leave twine and unlock windows, and then come back to use the twine as a weapon.
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Like BTK, he taunted police. In one call, he told police, "I'm the East Side Rapist, and I have my next victim already stalked, and you guys can't catch me."
That was March 18, 1977. Later that night, police responded to rape number 15.
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Rapes escalated to murders, and he became known as "the Night Stalker" in the papers. He ultimately admitted to killing 13 people in the late ‘70s and ’80s.
He was an old man in a wheelchair by the time he pleaded guilty to 13 murders and was sentenced to life in prison.
He agreed to admit to multiple uncharged crimes, including rapes, in exchange for taking the death penalty off the table.
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During his crime spree, he was a cop, a Vietnam vet and a married man.
He lost his job in the Auburn, California, police department in 1976 for shoplifting and divorced his wife, but lived with his daughter and granddaughter.
For 27 years, he was a "regular Joe," a former coworker told The Sacramento Bee, while he worked in a supermarket distribution warehouse for 27 years.
His case revolutionized cold case investigations after law enforcement used GEDmatch, a genealogy website that allows people to submit their DNA samples to explore their family tree.
About 20 distant relatives used the site, which narrowed the suspect pool. He was finally cuffed in 2018 when he was 72 years old and sentenced to life in prison in 2020.
This was considered the birth of forensic genealogy and sparked rapid advancements in DNA-testing technology, which was used to nab Heuermann in the Gilgo Beach murders case.
Police got his DNA from pizza crust that he threw out while investigators in a task force were surveilling him.
Suffolk County District Attorney Raymond Tierney said investigators had five "hairs of significance," which were further studied thanks to mitochondrial DNA technology.
"When people think of DNA, it's nuclear DNA that's the traditional DNA analysis that is done," Tierney said. "But as the science advanced and although the hairs were [too] degraded for nuclear DNA, we were able to use them for mitochondrial DNA."
