In February researcher Paul Haynes—who along with journalist Billy Jensen completed Michelle McNamara’s true crime masterpiece, I’ll Be Gone in the Dark—told me, “I have no doubt the case will be solved. This is inevitable. And once that happens, a whole new narrative will open up.”

Billy Jensen agreed. He said that while finishing the book, he and Haynes “focused on the two areas that we think are going to lead to identifying him—familial DNA and geographic profiling. He will be identified at some point, I have no doubt.”

Two months later they were proven right.

Alleged Golden State Killer Joseph James DeAngelo’s ancestors outed him through familial DNA. From the depths of the 18th century, some great-great-great grandparent’s stamp on the killer’s genes formed a red arrow pointing the way. Investigator Paul Holes was close to retiring, but he went hunting through a forest of family trees for this ghost with many names—East Area Rapist, Original Night Stalker, Golden State Killer. That was how he found DeAngelo.

As Joseph DeAngelo sat in court murmuring replies to the judge, his eyes seemed to betray a calculating creature inside, far more aware and alert than he seemed. It was easy to believe he was malingering, attempting to pull a “feeble, elderly retiree” defense. If so, his ruddy complexion and neighbors’ tales of an active septuagenarian suggested it was all an act. Maybe it was.

It’s long been believed that the Golden State Killer’s final murder was in 1986. Joseph DeAngelo would’ve been 41. Maybe the killer lost some of his athleticism—there were early reports of him climbing on rooftops, leaping fences—but he also had the confidence to subdue not just women but couples, as well. At least five of his confirmed murder victims were men.

Initial reports about DeAngelo indicate that at 72 he doesn’t appear to be an old man standing at the edge of an open grave. How out-of-shape was he in the late 1980s? Did he really stop? Did he only kill 12 after allegedly committing at least 50 rapes and 120 burglaries?

The second question may have some answers.

In November 1978 Simi Valley resident Rhonda Wicht and her four-year-old son Donald were found dead in her apartment. Wicht was strangled and her son smothered. Two years later, confirmed victims Lyman and Charlene Smith were murdered in Ventura County, not all that far away.

A man who’d been dating Wicht was convicted of the murders. Craig Coley went away for 40 years, only to be exonerated in 2017. His DNA didn’t match samples from the crime scene. Simi Valley police are waiting to see if the DNA is a match to the Golden State Killer.

A series of rapes and murders in Australia were so like the GSK crimes, U.S. authorities reached out to compare notes. “Mr Cruel” began stalking Melbourne suburbs in 1987, just after the GSK went to ground. His signature was almost identical. Mr Cruel subdued victims and bound them with complex knots. He prowled their homes, even eating meals. He talked to himself.

While the Golden State Killer wouldn’t hesitate to rape underage teen girls, Mr Cruel’s focus was entirely on girls younger than 13, and he abducted some victims as well.

Australian police see the similarities, but don’t think they are dealing with an international monster.

Online sleuths meticulously studying these crimes for years have wondered if the Visalia Ransacker was the same man—and Sacramento police agree. The Ransacker would enter homes in much the same way as the Golden State Killer and had a similar pattern of sometimes stealing inexplicably small, insignificant things.

The Ransacker had one known victim; journalism professor Claude Snelling, whom he shot as Snelling attempted to defend his daughter.

This Reddit thread is notable for listing several other crimes that resemble those committed by the Golden State Killer—including an eerily similar series of attacks that took place in Connecticut in June and July 1984. The GSK had no known connection to Connecticut—but there are many things we still don’t know.

So, what stopped him? Or did he stop?

Dennis Rader, the BTK Strangler, had several traits in common with Joseph DeAngelo. Both men were reportedly compulsively neat, and both were drawn to criminal justice. They majored in it, and the only reason Rader didn’t end up a cop is he failed required psychological tests. BTK and the GSK stalked their victims, learning habits and patterns before they attacked. DeAngelo and Rader both lived in quiet suburban enclaves for decades, unsettling neighbors but not much more than that. They were even born in the same year, 1945.

Rader suffocated, strangled, and stabbed ten people between 1974 and 1991. He targeted final victim Dolores Davis because she was older. Rader, then 46, didn’t see her as a challenge like his younger victims in the 70s. He admitted later he felt he’d lost a step and was more vulnerable to capture.

Did the Golden State Killer feel the same? Or did he change his methods enough to evade any detection of a pattern?

It’s still early. We’re going to find out.

***

Michelle McNamara wrote the killer a letter. I knew Michelle; I think she’d be okay with me quoting a portion.

She wrote, “One day soon, you’ll hear a car pull up to your curb, an engine cut out.”

Here’s how the end began: Police followed their DNA trail to DeAngelo’s address. According to CBS Sacramento was 8316 Canyon Oak Drive in Citrus Heights, California. They found a pleasant-looking home in a pleasant-looking neighborhood. They found a manicured lawn, bright green grass, three large decorative stones. They found an old man.

Michelle told him he would “hear footsteps coming” up his front walk. “Like they did for Edward Wayne Edwards, twenty-nine years after he killed Timothy Hack and Kelly Drew, in Sullivan, Wisconsin. Like they did for Kenneth Lee Hicks, thirty years after he killed Lori Billingsley, in Aloha, Oregon.”

Neighbors knew the old man as “Joe.” He was pleasant to some, scary to others, reported the Sacramento Bee. He’d been a cop when he was young, only to lose his job in the most embarrassing way: He was caught shoplifting dog repellent and a hammer. These go together if used in a certain order: first to ward off protective pets, then to murder their owners.

In her letter, it was as if Michelle was inside his house, and listening: “The doorbell rings.”

In his neighborhood, Joe was known as the old man who screamed obscenities to no one, sometimes acted strangely in other ways. He trespassed on a lawn once, stared at his neighbor there. He left a threatening voice mail about a barking dog. He was a “normal grandpa” but also “the kind of person you didn’t want to make mad.” He rode a motorcycle, sometimes went fishing; signs of an active elderly man.

“No side gates are left open,” Michelle wrote.

“You’re long past leaping over a fence. Take one of your hyper, gulping breaths. Clench your teeth. Inch timidly toward the insistent bell.

“This is how it ends for you.”

Police watched the “normal grandpa” for days. They managed to obtain his DNA. They had a perfect match. Almost two years to the day after Michelle McNamara passed away, they were ready.

Michelle used a killer’s words against him: “‘You’ll be silent forever, and I’ll be gone in the dark,’ you threatened a victim once.”

The day they came for him, one neighbor saw him building a table. Puttering, like retired men do. Around 4 pm, old Joe’s next-door neighbor heard something going on outside. She saw police cars, marked and unmarked. Officers in helmets, wearing vests.

Michelle wrote, “Open the door. Show us your face.”

The FBI joined the party, and 8316 Canyon Oak drive buzzed with activity as they collected evidence. It was a bright and beautiful California Spring day.

Michelle McNamara knew how it would be, and what he’d do next: “Walk into the light.”