Anyone who has watched Mindhunter on Netflix knows that the show's first season was sprinkled with a series of perplexing vignettes that seemingly had nothing to do with the plot of the show. In them, we see a man (Sonny Valicenti) who works for ADT Security Services in Kansas. He seems a little bit off, but why, we can't totally be sure.

In the newly released Mindhunter season 2, those vignettes continue. This time, they're much more bone-chilling — and it becomes obvious that the man we're seeing in these short scenes is the infamous BTK Killer. Still, though, Mindhunter takes place in the late 1970s and early 1980s, when the BTK Killer was not in prison, but very much in the midst of his violent crime spree. Which begs the question: How does BTK's story end?

To help answer that, we took a look back at BTK's crimes, and everything Mindhunter's mysterious vignettes haven't told you about Dennis Rader, the real BTK killer — yet.

Who was Dennis Rader?

In all facets of his public-facing life, Dennis Rader appeared to be just a "regular" guy. Born in 1945, Dennis spent his childhood in the Wichita, Kansas area, and after a brief stint in the U.S. air force, he eventually married a woman named Paula in 1971. The couple lived together in Park City, a suburb of Wichita, and had two children: a son and a daughter.

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Dennis Rader at his August 2005 sentencing hearing

After earning an associate degree in 1973 (he later earned a bachelor's degree, as well), Dennis went on to work a job at ADT Security Services, installing security alarms in local homes from 1974 to 1988. He then went on to hold a job as a city compliance officer, while also serving as the president of the Christ Lutheran Church council and a Cub Scout leader.

Little did everyone around him know that he was leading a double life.

The murders

On the afternoon of January 15, 1974, 15-year-old Charlie Otero and two of his siblings came home from school to find a horrific scene: Their parents, 38-year-old Joseph and 33-year-old Julie, and their two youngest siblings, 9-year-old Joseph Jr. and 11-year-old Josephine, had been brutally murdered in their Wichita home. The murders shook the small Kansas community, but the killer wasn't immediately found.

In 1978, however, a letter was sent to Wichita's KAKE news station, in which the writer claimed responsibility not only for the Otero family murders but also for the 1974 murder of Kathryn Bright, the 1977 murder of Shirley Vian, and the 1977 murder of Nancy Fox. In the letter, the murderer also suggested a nickname for himself: "BTK," standing for "bind, torture, kill."

sonny valicenti as dennis rader in mindhunter
Netflix
Sonny Valicenti as Dennis Rader in Mindhunter

In the years that followed, the BTK killer went on to murder three other people: Marine Hedge in 1985, Vicki Wegerle in 1986, and Dolores Davis in 1991. And during this murderous spree, he maintained correspondence with the press and the police, taunting them.

But then, suddenly, the BTK murders seemed to stop ... and all the related murder cases went cold.

Getting caught

It wasn't until 2004 that BTK began communicating with the press and police again. In March of that year, he sent a letter to The Wichita Eagle claiming he had murdered a woman named Vicki Wegerle back in 1986, even providing photos of the crime scene and a copy of her driver's license as proof. He was back.

Police claimed a floppy disk would be untraceable. Thankfully, BTK believed them.

BTK's taunting continued for months afterward, with haunting photos, evidence from the killer's crime scenes, and bizarre letters of sorts being dropped all over the city of Wichita. But eventually, police caught a break: In an early 2005 letter, BTK inquired if police might be able to trace a floppy disk back to him if he sent them one. In response, Wichita police published an ad in the newspaper claiming that a floppy disk would be untraceable. And thankfully, BTK believed them.

btk killer dennis rader - mugshot 2005
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Dennis Rader’s mugshot from his February 2005 arrest

On February 16, 2005, the BTK killer sent police a purple floppy disk filled with instructions for further communications. And within the metadata of that disk, police were able to find two key clues: the words "Christ Lutheran Church" and the name "Dennis." A quick internet search led them to Dennis — and after a search warrant allowed them to compare DNA from his daughter's recent pap smear to the DNA they had on file, the police found their man.

By early afternoon on February 25, 2005, Dennis Rader had been arrested.

Pleading guilty

On June 27, 2005 — the day that his trial was scheduled to begin — Dennis pleaded guilty to all 10 charges of murder filed against him. During his confession, he described each of the murders in detail, but he showed little emotion and no remorse ... and he offered no apologies.

btk killer dennis rader - sentencing hearing 2005
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Dennis Rader at his August 2005 sentencing hearing

Ultimately, Dennis was sentenced to 10 consecutive life sentences for his crimes. This included a "hard 40," or 40 years without the possibility of parole.

Where is Dennis Rader today?

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Today, Dennis Rader, now 74, continues to live out his sentences in solitary confinement at the El Dorado Correctional Facility in Butler County, Kansas. It might be awhile before we see this stage of his life in Mindhunter, though, if we ever do — seasons 1 and 2 of the Netflix show are set in the late 1970s and early 1980s, when Dennis (played in brief vignettes by actor Sonny Valicenti) was in the heart of his killing spree and decades from being caught.

In July 2005, Dennis's wife Paula was granted an "emergency divorce" from him, and since then, his family has remained mostly silent on the subject of BTK and his killings. This year though, Dennis's daughter, Kerri Rawson, released a book about her life since finding out her father was serial killer. The book, titled A Serial Killer's Daughter: My Story of Faith, Love, and Overcoming, is available for purchase on Amazon now.


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