Warning: This article contains spoilers for The Watcher.

As if a fact-based story about a family plagued by maniacal letters from an anonymous stalker wasn't terrifying enough, Ryan Murphy's The Watcher series also drew narrative inspiration from a true story about a mass murder that took place in the same New Jersey town as the 2018 Cut article the show is based on.

Episode 3, titled "Götterdämmerung," sees Nora (Naomi Watts) and Dean Brannock (Bobby Cannavale) delving deeper into the mystery surrounding the threatening messages that appear in their mailbox at 657 Boulevard in Westfield, N.J. After the suspect pool dwindles thanks to the supposed murder-suicide of nosy neighbors Mitch (Richard Kind) and Mo (Margo Martindale), Dean discovers a religiously obsessed man named John (Joe Mantello) — who claims to be a building inspector working with the crew remodeling the kitchen — making a sandwich in front of his refrigerator. Their conversation grows increasingly unnerving, with John urging Dean to take his family to a Lutheran church down the road while babbling about cyclical chaos breeding world destruction, until Dean becomes hostile and John departs.

Later, Dean's private investigator, Theodora (Noma Dumezweni), tells him a story about a man named John Graff, a past resident of Dean's property who, years prior, lost his lucrative job after moving his wealthy mother in with himself, his wife, and his two teenage children. As Theodora narrates, we see a flashback that reveals John Graff is the same present-day John who made himself a cold cut lunch in Dean's kitchen, and we learn that his psychological descent began after he lost his job and started siphoning money from his mother's savings account to keep up the illusion that he was employed.

Theodora continues, telling Dean that John, too, eventually received menacing letters from the Watcher, which preceded him shooting his wife in the back of the head inside the house. He later killed his mother on the second floor, waited for his daughter to return home from school before shooting her as well, and ultimately traveled to his son's basketball game, drove him back to the house, and shot him when they walked through the door. Between the slayings, we see John eating a sandwich and washing it down with a glass of milk.

The Watcher; Insurance executive John List was sought by police on suspicion of murder after the bodies of his wife, mother, and three teenaged children were found shot dead in his Westfield, New Jersey, home.

'The Watcher' episode 3 murder sequence involving John Graff (Joe Montello) is based on the real John List family murders of 1971.

| Credit: Netflix; Bettmann/Getty

It might seem like a fantastical, fictional bloodbath concocted for TV, but this sequence was inspired by the real crimes of John List, who, on Nov. 9, 1971, killed his entire family in identical fashion within their Westfield abode. List similarly lost his job, and gradually bled out his mother's $200,000 savings before killing her and his wife in the house. He also ambushed two of his children when they returned home from school, and it's rumored that he made himself lunch between the killings, after which he reportedly traveled to his oldest son's soccer game and shot him approximately 10 times later that night.

Police didn't find the Lists' bodies until nearly a month after they were killed, with police eventually entering the home on Dec. 7 after neighbors voiced concerns. List left a note, indicating that he ended their lives to protect them from an uptick in evil in the world.

The Watcher

Naomi Watts and Bobby Cannavale in 'The Watcher.'

| Credit: Netflix

List went on the run, and wasn't captured until around 22 million people watched an America's Most Wanted episode chronicling his crimes. A Richmond, Va. woman who saw the show told authorities she thought her neighbor, a churchgoing accountant named Robert Clark, looked like the image of List she'd seen on the program. Agents went to the man's home and discovered that Clark was actually List, who'd built a new life for himself in the Virginia suburbs. He was arrested in 1989, convicted and sentenced to five life terms in prison. He died in 2008 as a result of complications from pneumonia.

Though the search for List — who had nothing to do with letters sent to Derek and Maria Broaddus, the real family who received the notes at their Westfield home — came to an end, the real-life case that formed the basis for The Watcher series' fictional take remains unsolved.

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