Why the Hunt for the Zodiac Killer Turned Into a Terrifying Puzzle for the Ages

A 1969 cypher from the Zodiac, the never-caught serial killer who terrorized the Bay Area and taunted the media and police for years, has been decoded. Here's why this case remains obsession-worthy.

By Natalie Finn Nov 27, 2021 8:00 AMTags
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A serial killer is scary. A serial killer who was never caught, whose year-long reign of random terror just stopped—or did it?—for no particular reason...

Well, that's the stuff of nightmares. And, in the case of the murderer who called himself "the Zodiac," cultural infamy.

What could have been throwaway news—that a coded message mailed by the killer to the office of the San Francisco Chronicle in November 1969, one of multiple communiques he sent to the media in the course of demanding their attention during his deadly spree, had been cracked—instead resulted in the revving of search engines everywhere as folks of all ages brushed up on the particulars of the investigation.

It's a case that has spawned its own cottage industry driven by true crime junkies who can't get enough, a saga whose twists, turns and epic frustrations cannot be exaggerated.

This cryptogram, which came to be known as the "340 Cipher"—a large block of 340 letters and symbols that resembles a deranged word search, signed as always with a circle with a cross through it, which may have been the astrological sign invoking spirit and matter but also unmistakably the crosshairs of a sniper's gun—was solved by a three-person team of amateur codebreakers separated by thousands of miles. 

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While some of the messages were decoded half a century ago, the fact that it took 51 years to figure out this one is testament both to how crafty the killer could be, as well as to the strength of the grip his brief but destructive reign of terror had on not just Northern California, but on anyone who couldn't bear to let this puzzle go unsolved, for all these years. 

"This is exciting," David Oranchak, a web designer based in Virginia, told the San Francisco Chronicle in a Dec. 2020 interview. "We've been sitting on the solution since last Saturday [six days prior]. When I first started looking at the Zodiac ciphers all those years ago, I thought, 'Oh, I can just write a computer program and solve it,' but it's been kicking my ass all this time. Until now." Aiding his quest were Sam Blake, a mathematician in Australia, and Jarl Van Eykcke, a warehouse operator in Belgium. 

Oranchak said he'd been working on the Zodiac cipher since 2006, which can't help but bring to mind the efforts of Chronicle political cartoonist turned Zodiac expert and author Robert Graysmith, who was working at the paper when the messages started arriving (he simply had an affinity for puzzles, he would explain) and couldn't let the case go.


Part of the message read, according to Oranchak, "I hope you are having lots of fun in trying to catch me. ... I am not afraid of the gas chamber because it will send me to paradice (sic) all the sooner because I now have enough slaves to work for me."

The results of the team's efforts were duly forwarded along to the FBI, which acknowledged receiving the information.

"The Zodiac Killer case remains an ongoing investigation for the FBI San Francisco division and our local law enforcement partners," the Bureau's San Francisco office said in a statement posted to social media (and Twitter users kept on making their own adjustments to the message right there in the thread). "The Zodiac Killer terrorized multiple communities across Northern California, and even though decades have gone by, we continue to seek justice for the victims of these brutal crimes."

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The Zodiac had seven known victims, five of whom died: Betty Lou Jensen and David Faraday, two high school kids who were on their first date when they were shot to death while parked on a known lover's lane turnoff in Benicia; Darlene Ferrin, whose date Michael Mageau survived the shooting attack in Vallejo; Cecelia Ann Shepard, stabbed to death at a lake in Napa County, while her friend Bryan Hartnell survived eight stab wounds to the back; and Paul Stine, a cab driver shot to death in the Presidio Heights neighborhood of San Francisco.

The murders occurred between Dec. 20, 1968, and Oct. 11, 1969. Along the way, he raised the possibility of committing many more, threatening in one cipher to shoot up a bus full of school children. (In Dirty Harry, the Zodiac-inspired Scorpio Killer who Clint Eastwood's rogue SFPD inspector faces off against does hijack a school bus.)

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While no arrest was ever made, like with Jack the Ripper, like with the Black Dahlia killer, more than a few names have been floated over the years as possible perpetrators, from a mentally ill library assistant who resembled one of the police sketches to a member of the Manson Family. But in his 1986 book Zodiac, Graysmith zeroed in on Arthur Leigh Allen, who was questioned in 1969 and who police came back to time and again over the course of 20 years, long after the Zodiac stopped sending letters proudly taking credit for an increasing number of murders.

Allen, who did spend two years in prison in the 1970s for sexually abusing a 12-year-old boy, died in 1992. In the 2007 film Zodiac directed by David Fincher and based on the book of the same name, he's played by John Carroll LynchJake Gyllenhaal played Graysmith, whose family life is seen ending up on the backburner while he becomes increasingly immersed in his pursuit of the killer, and Robert Downey Jr. was ace crime reporter Paul Avery, who walked the Zodiac beat for the Chronicle and received mail from the killer addressed directly to him.

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Eerily, on Dec. 21, 1968, Darlene Ferrin had mentioned to Bobbie Ramos, a co-worker at the Vallejo coffee shop where she was a waitress, that she knew the kids who'd been shot to death the night before, Betty Lou Jensen and David Faraday. 

"One thing about Darlene," Ramos told Graysmith, "she talked to everyone. I used to tell her, 'Don't talk to everybody, everybody's not your friend. You just think they are.' She was so friendly, people waited in line to get in her section." A 22-year-old with braces, Ferrin "looked more like 17," Ramos said. "And acted 17."

Ferrin told Ramos in June 1969 that she was sure a man in a white car had been watching her, but never explained why. On July 4, she made plans to go to the movies in San Francisco with her friend Mike Mageau—who along with his twin brother David had a mad crush on the twice-married young mom—that night. The plan changed, but that night, they were in Ferrin's Corvair when a car zoomed up behind them and wouldn't let up, following them for several minutes, seemingly urging them toward a remote parking area, another known lover's lane.

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The car pulled in after them and parked about eight feet away. The driver sped off, but then returned five minutes later, Mageau would later tell police, having managed to avoid being fatally wounded by hurtling himself into the backseat. A trio of teens who pulled into the lot looking for some friends discovered the grisly scene. Darlene was pronounced dead at a nearby hospital at 12:38 a.m. on July 5.

At 12:40 a.m., according to Graysmith's Zodiac, Vallejo Police got a payphone call from a man who said, "I want to report a double murder. If you will go one mile east on Columbus Parkway to the public park, you will find kids in a brown car. They were shot with a 9-millimeter Luger. I also killed those kids last year. Goodbye."

The first letter addressed to the San Francisco Chronicle arrived Aug. 1, 1969, and two similar ones were sent to the San Francisco Examiner and Vallejo Times-Herald. Along with all three, portions of a cipher comprising eight lines of 17 symbols each. Graysmith recalled being hooked almost instantly.

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In the handwritten letter, the sender took credit for the double homicide the previous Christmas and "on the girl on the 4th of July near the golf course in Vallejo." He included facts seemingly no one else would know, such as that 10 shots had been fired killing Faraday and Jensen," and that Ferrin had been wearing "paterned [sic] slacks."

He also threatened, in what came to be his recognizably misspelling-laden way, to "go on a kill ram-Page Fry. night" if the papers didn't print their portions of the cipher on their front page in full. "I will cruse around all weekend killing lone people in the night then move on to kill again, untill I end up with a dozen people over the weekend."

The newspapers ran the ciphers, and on Aug. 4, a Salinas high school teacher and his wife called the Chronicle. They had cracked it, beating the CIA, FBI and National Security Agency.

"I like killing people/because it is so much/fun it is more fun than/killing wild game in the forrest because/man is the most dangeroue anamal of all..." it read in part (with errors intact). At the bottom: a row of letters in no intelligible order.

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Responding to Vallejo Police Chief Jack Stiltz's skeptical public entreaty for the letter writer to send another one "with more facts to prove" that he really was the killer, he obliged with a three-page letter on Aug. 7, the first using his preferred nickname.

"Dear Editor, This is the Zodiac speaking," the rambling letter began.

When the solution to the cipher was published Aug. 12, armchair detectives and puzzle enthusiasts started calling the Chronicle with their own names culled from the letters at the bottom, guessing it had to be an anagram for the killer's identity. 

But while no spree followed, the Zodiac perhaps momentarily satisfied by all the attention he was getting, he wasn't done.

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On the afternoon of Sept. 27, 1969, college student Cecelia Ann Shepard, who was planning a transfer down south to UC Riverside, was enjoying an impromptu goodbye outing with pal Bryan Hartnell at Lake Berryessa in Napa. They were lying on the otherwise deserted beach when Shepard spotted a man in a black hood coming toward them. At first Hartnell thought it was some sort of a prank, that maybe a friend had followed them out there.

When the masked man, who had a holstered gun and a sheathed knife attached to his belt, demanded money and his car keys, Hartnell felt that at least nothing worse was happening than a mugging. They actually conversed for several minutes, Hartnell telling the man he hardly had any money on him, but he was welcome to his change. He even asked whether the gun was loaded, and the man took a bullet out to show him.

Even when the man hogtied the both of them, Hartnell remembered, he still didn't expect anything worse. But then, the man said, "I'm going to have to stab you people."


Hartnell insisted that he be stabbed first, that he couldn't bear to see Shepard hurt. He was stabbed repeatedly in the back, but remained lucid enough to witness Shepard get stabbed 24 times. "When you really look at exactly what happened to me, you'll see I was extremely fortunate...Just a fraction of an inch to the right and I would have been dead," he later told Graysmith. A fisherman and his son out in a rowboat eventually spotted the pair from the water, but they didn't approach, instead heading toward the Rancho Monticello Resort two miles away to report the attack.

Hartnell managed to crawl about 300 yards, and that's where the local rangers found him. Shepard was still alive, but died of her injuries at a hospital on the afternoon of Sept. 29.

Meanwhile, the killer had written in black felt-tip pen on the front passenger side door of Hartnell's white Volkswagen Karmann Ghia:

Sept 27-69-6:30
by knife."

He added the crosshairs symbol.

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On Oct. 11, 1969, a cab driver named Paul Stine was called to Ninth Avenue in San Francisco. A man got in and gave Stine an address in Presidio Heights, which he dutifully wrote in his trip log. About a dozen blocks away, stopped at the corner of Washington and Cherry, the passenger shot Stine in the head.

He then got into the front passenger seat to get the driver's wallet, tear off a piece of his shirt and wipe down the inside of the taxi—all of which was witnessed from an unfortunately dark and misty distance by a group of teenagers in an apartment where a party was taking place. A 14-year-old girl had seen this scene unfolding from her window, then called her 16-year-old brother over. Police were called at 9:58 p.m.

One of the patrolmen who responded would later realize he'd called out to the killer himself, a stocky man he spied across the street walking toward the Presidio, to ask if he'd seen anything. The man, whose dark clothes were covered in blood, had shouted back that he'd seen a guy waving a gun, running east on Washington. And so a police car went that-away.


If the killer hadn't sent a piece of Stine's bloody shirt to the Chronicle with a crosshairs symbol on the envelope instead of a return address, it's unclear how long it would've taken to link the murder to the Zodiac, considering the wildly different M.O.

The letter taking responsibility for the cabbie's killing was the one that ended with a threat to massacre school children, the Zodiac writing, "School children make nice targets, I think I shall wipe out a school bus some morning. Just shoot out the front tire & then pick off the kiddies as they come bouncing out."

Much debate ensued over whether to publish that, because it would obviously cause a panic—which it did when it was printed on Oct. 17. The 65 school buses on the job for 28 schools in Napa were given armed police escorts.

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But while the Zodiac killings seemingly stopped in October 1969 as the country's attention headed south, to the capture of the people responsible for the August murders of actress Sharon Tate and six others in Los Angeles, the messages did not.

He sent a greeting card to the Chronicle on Nov. 8, 1969, as well as a new cipher—the 340 cipher that wouldn't be decoded until December 2020. A seven-page letter declaring "The police will never catch me, because I have been too clever for them" arrived the next day, decorated with a drawing of the inside of a bomb.

The Zodiac also wrote to famed attorney Melvin Belli, who had been a guest on Jim Dunbar's AM San Francisco show that October when a man purporting to be the Zodiac killer called in. The letter was sent to the lawyer's residence, where it was lost in a pile of Christmas mail and not opened until Dec. 27, after which an associate flew with a photocopy of the letter to Munich to hand it to Belli in person. In it, the Zodiac seemed to be taking credit for another murder. 

"I believe he wants to stop killing," Belli, who via the Chronicle relayed a message that he'd meet in person with the Zodiac any time at a place of his choosing, told reporters afterward. "I have carefully studied his letter...and feel it was written at a time when he calmly and rationally was considering a future."

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Belli wouldn't hear from him again for months. (Incidentally, the 340 Cipher also notes, "That wasnt [sic] me on the TV show," seemingly referring to the Dunbar call-in.)

In the ensuing months, killings that shared attributes with the crimes Zodiac had admitted to were investigated for ties to the serial killer, and his own tally continued to climb in his letters, but the aforementioned five deaths and two other victims remain the only confirmed Zodiac murders. 

He alluded to bombs, created more ciphers of varying lengths, drew ultimately unhelpful maps and, on July 27, 1970, two letters arrived at the Chronicle.

It was then they decided to see what would happen if they didn't print his messages.

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On Oct. 6, 1970, the Chronicle received a 3x5 index card with a message punctuated by a cross drawn in blood.

A children's Halloween card came addressed to Paul Avery at the office on Oct. 27, 1970, reading "PEEK-A-BOO YOU ARE DOOMED!" with a picture of a skeleton pasted inside.

Talking to KRON-TV on Oct. 31, the journalist shrugged it off, saying, "I think that the Zodiac is just making an idle threat, frankly. He has bragged of killing up to possibly 14 people, but there's absolutely no evidence...I put no credence in this. I think he wanted to get himself a little publicity." Noting other killings that were grabbing media attention, Avery surmised that he might be "a little miffed, he's not the center of attention anymore."

Sure enough, he had become front-page news once again with the Halloween stunt. (And the letters from July were eventually published on Oct. 12.)

KRON-TV News footage

Asked for his opinion of what type of person the killer was, Avery said, "Well obviously a very sick person. He's very cunning, too. He's not a brilliant man but...he certainly isn't dumb. I think he's got a kind of a shrewd, animal cunning to him. And of course there's a great sickness in there that prompts him to go out and kill."

And he wasn't going to ignore the threat entirely, either. "I'm no fool," Avery said. "I'm going to be very careful. There was a conference with the police department, a discussion of possible police protection for me." But for now, they found it unnecessary. "If someone takes a shot at me," he added with a smile, "that'll be a different case." 

Avery died of emphysema in 2000 at the age of 66, but a former colleague insisted after Zodiac came out that he was not ruined by the case, the way the film implies. His smoking did hasten his decline, but he remained a hard-charging journalist, also known for his Sacramento Bee coverage of heiress Patty Hearst's kidnapping and subsequent trial for her role in a bank robbery, as well as a book about the case, The Voices of Guns.

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Before his run at the Chronicle ended though, Avery reported that the Zodiac may have been responsible for the 1966 murder of an 18-year-old college freshman in Riverside, Calif., the city's only unsolved homicide at the time. Gruesome notes had been sent to the victim's father and the Riverside Police Department.

That prompted the Zodiac to write to the more geographically desirable Los Angeles Times for the first time, on March 15, 1971. A week later, a postcard addressed to "Paul Averly" showed up at the Chronicle, covered in cut-outs from other papers, including scraps that read "sought victim 12," "pass LAKE TAHOE areas" and "around in the snow." An ad for a condo complex in Tahoe called Forrest Pines was glued to the back

At the time, a nurse and former San Francisco resident named Donna Lass had been missing since Sept. 6, 1970. Her car was found parked near her apartment in Stateline, Nev., on the southeastern side of Lake Tahoe, but Lass was nowhere to be found. 

"Since we haven't any other suspect in the case, I suppose the Zodiac theory is as good as any," South Lake Tahoe Police Chief Ray Lauritzen said at the time. They were checking because of the postcard.

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While a couple of detectives remained on the case, the Zodiac wouldn't write to the Chronicle again until Jan. 30, 1974, when he promised, "if I do not see this note in your paper, I will do something nasty, which you know I'm capable of doing."

The slightest chance that any message would hold a clue as to his identity or whereabouts proved too alluring to ignore, but his sign-off—"Me-37 SFPD-0" was also a chilling reminder that they didn't really know that he hadn't killed dozens of people.

By 1976, the bowtie-and-suspenders-wearing Dave Toschi, who came onboard the investigation when Stine was killed, remained the only San Francisco detective still technically on the case—but was removed in 1978 when he admitted to sending a few letters to newspapers using a fake name to praise his work. He admitted it was "a foolish thing to do." (He denied ever writing a letter purported to be from the Zodiac.)

On April 24, 1978, a letter to the Chronicle stated, "This is the Zodiac speaking I am back with you...That city pig toschi is good - but I am smarter and better he will get tired then leave me alone. I am waiting for a good movie about me. who will play me. I am now in control of all things."

Toschi died in 2018 at 86. He acknowledged to the LA Times at one point, "Looking back, I feel mostly frustration. That case took so much out of me." And like Graysmith, he thought Allen was their man.


Mark Ruffalo, who played Toschi in the film, said in a 2007 interview, "You realize how they have to take their hunches, their personal beliefs, out of it. Dave Toschi said to me, 'As soon as that guy walked in the door, I knew it was him.' He was sure he had him, but he never had a solid piece of evidence. So he had to keep investigating every other lead."

Though Graysmith felt confident that Allen's death in 1992 meant that the opportunity to put the killer behind bars died with him, he became no less enmeshed in the case. Having started work on his book Zodiac when it became apparent to him that law enforcement and the media had more or less moved on, he released Zodiac Unmasked in 2002 and helped Fincher and Gyllenhaal recreate the 1960s-era world of the Chronicle, down to what pens he used to draw his cartoons, for the 2007 film.

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"I don't think it's good writing, a dashing detective or whatever," he told Newsweek, musing about the enduring fascination with the Zodiac. "It's the bizarre costume and the cryptograms. It has been called the most cerebral murder case of all time. You have to take the human anguish, the human loss out of the equation to solve this, you could not deal with it. You have to look at the ciphers and the odd costume. You realize there are still cryptograms that haven't been broken, such as 'My name is …' or a map, 'This is where to find me.'"

Hence the decades of work put in to crack one of the puzzles the Zodiac left, a brainteaser that kept amateur sleuths busy right through 2020, the macabre breakthrough fitting right in with the rest of the year.

"Anybody with any sort of curiosity wants to know the entire story," Graysmith continued. "The only thing we had comparable to this back in 1969 was Jack the Ripper, and there are about a hundred books, and they all have a different ending."

He also had his explanations at the ready for the fact that, in 2002, San Francisco police had formed a partial DNA profile recovered from the stamps and envelopes the Zodiac used, and further testing excluded Allen. 

Starting with the fact that countless hands had handled those materials over the years, and over time they'd sat in uncontrolled climates. And, he added, wouldn't the Zodiac at least have been savvy enough not to leave any physical trace on his letters, even if DNA traces were not even a glimmer in forensic-minded eyes yet.

At the same time, Graysmith said, "If that is your best piece of evidence in history, get out there and run with that. Let's just say Zodiac is someone we never heard of. There's nothing wrong with that; they are going to get him because the case has been kept alive and that's why I tell everybody, that's when I'll write a last chapter. It does not bother me in the least. But you know, that's why it's a mystery, and the fact that there's doubt is going to keep it a mystery for centuries."

According to the Chronicle, there are two other ciphers sent to papers decades ago that remain unsolved—and perhaps it's one of them that will provide the key to unlocking the Zodiac's identity beyond a shadow of a doubt.

This story was originally published on Tuesday, Dec. 15, 2020 at 10 a.m. PT.