The Zodiac Killer: Letters, Ciphers, Five Confirmed Murders, and No Arrest Ever Made

Estimated read time: 14 minutes  |  Category: Unsolved Mysteries  |  Last updated: June 2025

The Killer Who Wrote His Own Headlines

Most murderers want to disappear. The Zodiac Killer wanted to be famous.

Between December 1968 and October 1969, a killer operating across Northern California attacked at least seven people — killing five — in a series of apparently random assaults on couples at isolated locations. The crimes were brutal. The victims were ordinary people in the wrong place at the wrong time. And the killer, rather than fleeing into obscurity, did something that guaranteed his case would never be forgotten.

He wrote letters.

To newspapers across the Bay Area, the Zodiac — as he named himself — sent taunting, boastful correspondence that included coded ciphers he claimed contained his identity, threats of more killings, and a running commentary on the investigation that was failing to catch him. He wore a costume to one attack. He called police after another. He sent pieces of a victim’s shirt to prove he was real.

He was never caught. Never identified. Never charged.

More than fifty years later, the Zodiac Killer remains one of the most studied, most theorised, and most haunting unsolved criminal cases in American history — a mystery sustained not just by the killings, but by the letters, the ciphers, and the killer’s apparent desire to be remembered.

---

What We Know For Certain

• [FACT] The Zodiac Killer is confirmed to have killed at least five people across four attacks in Northern California between December 20, 1968 and October 11, 1969.
• [FACT] The killer himself claimed responsibility for 37 murders in his letters. This figure has never been verified and is widely considered an exaggeration by investigators.
• [FACT] The Zodiac sent at least 20 confirmed letters to newspapers and law enforcement, including the San Francisco Chronicle, San Francisco Examiner, and the Vallejo Times-Herald.
• [FACT] The letters included four ciphers. The first — the Z408, sent in three parts to three newspapers in July 1969 — was decoded within a week by a high school teacher and his wife. It contained no name.
• [FACT] The second major cipher — the Z340, sent in November 1969 — remained unsolved for 51 years until a team of amateur codebreakers cracked it in December 2020. It also contained no name.
• [FACT] The Zodiac case was officially investigated by multiple law enforcement agencies including the San Francisco Police Department, Vallejo Police Department, Napa County Sheriff, and the FBI. No one has ever been formally charged.
• [FACT] The case remains officially open with both the San Francisco Police Department and the FBI.

---

The Confirmed Attacks

Attack 1 — Lake Herman Road, December 20, 1968

[FACT] David Faraday, 17, and Betty Lou Jensen, 16, were shot and killed while parked on Lake Herman Road near Benicia, California. Faraday was shot once in the head. Jensen was shot five times in the back, having apparently tried to run. There were no witnesses. No motive was established. The killer left no confirmed physical evidence linking them to subsequent attacks at the time — it was only later correspondence that connected this crime to the Zodiac.

Attack 2 — Blue Rock Springs, July 4, 1969

[FACT] Darlene Ferrin, 22, and Michael Mageau, 19, were attacked while parked at Blue Rock Springs Park in Vallejo. The attacker approached the car, shone a bright light through the window, and opened fire. Ferrin was killed. Mageau survived despite being shot multiple times. He later provided a physical description of the attacker: a heavyset white male in his early to mid-twenties with light brown curly hair.

[FACT] Approximately forty minutes after the attack, Vallejo Police Department received a call from a man who calmly gave the location of the shooting, described it as a double murder, and also claimed responsibility for the Lake Herman Road killings. The call was recorded. It remains one of the only recordings of the Zodiac’s voice — though the voice’s identity has never been confirmed.

Attack 3 — Lake Berryessa, September 27, 1969

[FACT] Bryan Hartnell and Cecelia Shepard were picnicking on the shore of Lake Berryessa in Napa County when a man wearing a black hood with a cross-circle symbol — the Zodiac’s emblem — approached them. He tied them up, stabbed them repeatedly, and wrote on Hartnell’s car door with a felt-tip pen: the dates of previous attacks and the words “by knife.” Shepard died two days later. Hartnell survived and provided detailed descriptions of the attacker and the encounter.

[FACT] The attacker called Napa County Sheriff’s dispatch after the attack to report it. The payphone he used was later examined — investigators found a partial palm print that was never matched to any known suspect.

Attack 4 — Presidio Heights, October 11, 1969

[FACT] Cab driver Paul Stine, 29, was shot and killed in the Presidio Heights neighbourhood of San Francisco. The killer took a piece of Stine’s shirt. Witnesses in a nearby house observed the attacker and called police, providing a description. Two police officers drove past a man matching the description shortly after the murder but were incorrectly informed the suspect was a Black male — the actual suspect was white — and did not stop him.

[FACT] The piece of Stine’s shirt was subsequently sent to the San Francisco Chronicle with a Zodiac letter — proving the writer was the killer. DNA extracted from the envelope flap has been preserved but has not produced a confirmed match to any identified suspect.

---

The Letters

The Zodiac’s correspondence is as central to the case as the killings themselves. His letters are simultaneously the most valuable evidence in the investigation and the most frustrating — rich in detail, carefully constructed, and ultimately revealing almost nothing about his identity.

[FACT] The first confirmed Zodiac letters arrived at three Bay Area newspapers on August 1, 1969 — three weeks after the Blue Rock Springs attack. Each letter contained one third of the Z408 cipher. The letters demanded front-page publication of the ciphers or the writer threatened to “go on a kill rampage.” All three newspapers complied.

[FACT] The letters showed a consistent personality: arrogant, taunting, occasionally playful, always controlling. The Zodiac gave himself his name, designed his own symbol, kept a claimed body count, and appeared to enjoy the attention and the investigation’s failures with undisguised relish.

[FACT] The letters also contained demonstrable lies and exaggerations. The claimed body count of 37 was almost certainly false. Some claimed attacks cannot be corroborated. Investigators believe the Zodiac deliberately included false information to mislead.

[FACT] The final confirmed Zodiac letter was received in 1974, addressed to attorney Melvin Belli and containing a greeting card. Whether the Zodiac continued to kill after 1969, stopped killing, or died, has never been established.

---

The Ciphers

The Z408 — Solved in One Week

[FACT] The Z408 was a 408-character cipher sent in three parts to three newspapers in August 1969. Donald Harden, a high school history teacher, and his wife Bettye solved it within a week using frequency analysis and pattern recognition. The decoded message was a rambling statement about killing being pleasurable and the Zodiac collecting slaves for the afterlife. It did not contain his name.

The Z340 — Solved After 51 Years

[FACT] The Z340 — a 340-character cipher sent in November 1969 — resisted decryption for over half a century. Professional cryptographers, NSA analysts, and hundreds of amateur codebreakers all failed. In December 2020, a team of three amateur codebreakers — David Oranchak, Sam Blake, and Jarl Van Eycke — cracked it using a combination of computational analysis and pattern recognition. The decoded message contained more taunting language about police incompetence and the afterlife. It did not contain his name.

The Unsolved Ciphers

[FACT] Two Zodiac ciphers remain unsolved as of 2025. The Z13 — a 13-character cipher sent with the letter “My name is” — is believed by many to contain the Zodiac’s actual name. It has resisted every decryption attempt. The Z32 is a 32-character cipher that may contain location information. Neither has been definitively solved.

---

The Suspects

Over fifty years, investigators and amateur researchers have named dozens of suspects. None has been formally charged. Several have attracted sustained attention:

Arthur Leigh Allen

[FACT] Arthur Leigh Allen, a convicted sex offender who died in 1992, was the primary named suspect in Robert Graysmith’s influential 1986 book Zodiac and in David Fincher’s 2007 film of the same name. Allen matched several circumstantial criteria: he owned a Zodiac watch with the crosshairs symbol, had been at Lake Berryessa on the day of the attack, and made statements to acquaintances consistent with the Zodiac’s letters. [FACT] However, Allen’s handwriting did not match the Zodiac’s letters, his fingerprints did not match prints recovered from the case, and DNA extracted from Zodiac letters did not match Allen’s DNA profile. He was never charged.

Lawrence Kane

[THEORY] Researcher Harvey Hines and others have proposed Lawrence Kane — a man who suffered a personality change after a serious car accident — as a suspect. Kane lived near several attack sites, and some researchers claim to have found connections between his movements and the timing of the crimes. [FACT] No physical evidence links Kane to the crimes and he was never formally investigated as a primary suspect by law enforcement.

Gary Francis Poste

[FACT] In 2021, a cold case investigation team called the Case Breakers publicly named Gary Francis Poste — a house painter who died in 2018 — as their primary Zodiac suspect. The team claimed facial comparison analysis, alleged scars visible in both Poste’s photos and a composite sketch of the Zodiac, and anagrams of Poste’s name within the decoded Z408 cipher. [FACT] The FBI reviewed the Case Breakers’ findings and did not alter the case’s status. The Zodiac case remains officially unsolved and no suspect has been named by law enforcement.

---

What the Evidence Tells Us About the Zodiac

Despite the lack of identification, the evidence paints a reasonably consistent picture of the killer:

• [FACT] Multiple witnesses described a heavyset white male, approximately 5’8″ to 6′ tall, with light brown or reddish hair, in his late 20s to early 40s.
• [FACT] The letters demonstrate above-average intelligence and some familiarity with cryptography and codes.
• [FACT] The letter writing style is consistent across confirmed letters — suggesting a single author with a distinctive personality: controlling, narcissistic, and deeply concerned with public attention.
• [THEORY] Forensic linguists who have analysed the letters suggest the writer had at minimum a high school education, possibly some college, and showed signs of a personality that craved recognition while simultaneously hiding behind anonymity.
• [FACT] DNA has been extracted from envelope flaps on confirmed Zodiac letters. The profile is incomplete but has been compared against multiple suspects. No confirmed match has been found.

---

Why Was He Never Caught?

The Zodiac’s evasion of capture for so long reflects a combination of factors that made the case uniquely difficult:

• Jurisdiction fragmentation: The attacks occurred across multiple counties with different police departments — Solano, Napa, San Francisco — who did not initially share information effectively. There was no centralised investigation until the case was already cold.
• No apparent motive or victim selection pattern: The victims appeared to be chosen opportunistically — couples at isolated locations — with no obvious personal connection to the killer. Without a motive, investigators had no natural starting point for identifying a suspect.
• The witness description problem: Different witnesses gave slightly different descriptions. The composite sketches produced from witness accounts do not entirely agree with each other.
• Pre-DNA forensics: The attacks occurred before DNA profiling existed. Physical evidence that was preserved was not analysed with modern techniques until decades later, by which point contamination and degradation had significantly limited its value.
• The letter writing: [ANALYSIS] Paradoxically, the Zodiac’s letter writing — while generating enormous amounts of evidence — may have helped him evade capture by controlling the narrative. He decided what information investigators had. He introduced false leads deliberately. The letters generated thousands of tips that required investigation and consumed resources.

---

The Cultural Legacy

The Zodiac Killer has had an outsized cultural impact relative even to other famous unsolved crimes — partly because of the letters, partly because of the San Francisco setting, and partly because of the quality of journalism and creative work the case inspired.

[FACT] Robert Graysmith’s 1986 book Zodiac was a meticulous reconstruction of the case that introduced the Allen theory to a wide audience. David Fincher’s 2007 film adaptation — widely considered one of the finest true crime films ever made — brought the case to a new generation and sparked renewed amateur investigation.

[FACT] The Zodiac case has directly influenced the presentation of other serial killer cases in media and popular culture, establishing the template of the letter-writing, cipher-sending, identity-teasing killer that has been replicated in fiction dozens of times.

[ANALYSIS] The Zodiac understood something that most criminals do not: that controlling the story is a form of power. By naming himself, designing his symbol, sending his letters, and managing his public image, he ensured that the case would never quietly close. He built his own mythology and handed it to the press. Fifty years later the mythology endures — which may have been exactly what he intended.

---

Conclusion

Five confirmed victims. At least seven attacks. Twenty confirmed letters. Four ciphers — two solved, two still open. Dozens of named suspects. Zero arrests.

The Zodiac Killer case is unsolved not because investigators failed to work it — they worked it exhaustively, across multiple agencies, for decades — but because the killer appears to have been careful, intelligent, geographically mobile, and either very lucky or very deliberate in leaving minimal traceable evidence.

The DNA profile extracted from his letters sits in a database waiting for a match. The Z13 cipher — believed by many to contain his name — has not been cracked. The case files remain open.

Somewhere, the answer exists. In a database. In an archive. In a cipher. In the memory of someone who knew a man with an unusual habit of following murder cases very closely in the newspapers.

The Zodiac signed his letters with a crosshairs symbol — a circle divided by a cross. He is still in the crosshairs. We just have not found him yet.

---