Active Investigation
1960s
San Francisco Bay Area, CA
Unsolved Murder
Official

The Zodiac Killer

Ciphers, Letters, and an Unidentified Killer

26 evidence items1 investigatorUnsolved Murder3 boards created

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Case Dossier

Case Brief

The Zodiac Killer operated in Northern California in the late 1960s and early 1970s, killing at least five confirmed victims. The killer taunted police and newspapers with letters and cryptograms, some of which remain unsolved to this day. Despite numerous suspects and DNA advances, the case remains officially open.

Evidence Archive

5

Documents

8

People

5

Locations

2

Timeline Events

5

Notes

Key Figures

Key Locations

Presidio Heights — Paul Stine Murder Site

3898 Washington Street, San Francisco, California

San Francisco Chronicle Office

901 Mission Street, San Francisco, California

Blue Rock Springs Park

650 Columbus Parkway, Vallejo, California

Lake Herman Road Attack Site

Lake Herman Road, Benicia, California

Lake Berryessa Attack Site

Napa, California, United States, Napa, California

Timeline Highlights

Sep 27, 1969

Car Door Message at Lake Berryessa

Following the stabbing of Bryan Hartnell and Cecelia Shepard at Lake Berryessa, the attacker walked to Hartnell's white Volkswagen Karmann Ghia in the parking area and wrote a message on the passenger-side door with a black felt-tip pen. The message read: Vallejo 12-20-68 7-4-69 Sept 27-69-6:30 by knife Above the text, the attacker drew the crosshair symbol associated with the Zodiac. The message effectively claimed credit for all three attacks, listing the dates of the Lake Herman Road shooting, the Blue Rock Springs shooting, and the current stabbing. The car door was removed and preserved as evidence by the Napa County Sheriff's Office.

Dec 5, 2020

The 340-Cipher Solution — December 2020

In December 2020, a team of three amateur codebreakers — David Oranchak, Sam Blake, and Jarl Van Eycke — announced they had cracked the Zodiac's 340-character cipher, which had resisted professional and amateur efforts since November 1969. The team used specialized software to test millions of possible transposition schemes and identified that the cipher used a combination of homophonic substitution and a complex rearrangement pattern that read diagonally across the message. The decoded text taunted law enforcement but did not reveal the killer's identity. The FBI confirmed the validity of the solution in December 2020. The decoded message contained statements about the killer not being afraid of the gas chamber and continued his theme of collecting slaves for the afterlife.

Frequently Asked Questions

What happened in the Zodiac Killer case?
The Zodiac Killer operated in Northern California in the late 1960s and early 1970s, killing at least five confirmed victims. The killer taunted police and newspapers with letters and cryptograms, some of which remain unsolved to this day. Despite numerous suspects and DNA advances, the case remains officially open.
Is the Zodiac Killer case solved?
No, the Zodiac Killer case remains unsolved as of 2026. 1 citizen investigator is actively reviewing 26 pieces of evidence on Coldcase Bureau, including 5 documents and 8 identified persons of interest.
Who are the key people in the Zodiac Killer case?
Key figures in the Zodiac Killer investigation include Paul Stine, Darlene Ferrin, Bryan Hartnell, Arthur Leigh Allen, Dave Toschi. The full case archive identifies 8 people connected to the case, with documented relationships, evidence links, and connection maps between individuals.
Where did the Zodiac Killer case take place?
The Zodiac Killer case is primarily associated with San Francisco Bay Area, CA. Key locations include Presidio Heights — Paul Stine Murder Site, San Francisco Chronicle Office, Blue Rock Springs Park. The evidence archive documents 5 locations connected to the case.
When did the Zodiac Killer case happen?
The Zodiac Killer case dates to the 1960s. The investigation timeline documents 2 key events in chronological order, from the initial incident through the ongoing investigation.
What evidence exists in the Zodiac Killer case?
The Zodiac Killer evidence archive contains 26 pieces of evidence including 5 documents (court filings, police reports, FOIA responses), 8 identified persons, 0 organizations, and 5 mapped locations. All evidence is sourced from publicly available records and organized on interactive investigation boards.
What are the main theories in the Zodiac Killer case?
The Zodiac Killer investigation features multiple competing theories developed by 1 citizen investigators on Coldcase Bureau. Each theory is supported by evidence from the 26-item archive, with investigators creating focused investigation boards to map connections and test hypotheses. Join the investigation to review existing theories or propose your own.
Why hasn't the Zodiac Killer case been solved?
The Zodiac Killer remains one of over 250,000 unsolved cases in the United States. Factors may include limited forensic technology at the time, witness reliability issues, or investigative dead ends. Coldcase Bureau enables citizen investigators to collaboratively review all 26 pieces of archived evidence, identify new connections using interactive investigation boards, and develop theories that traditional investigations may have missed.
How can I help investigate the Zodiac Killer case?
You can join the Zodiac Killer investigation on Coldcase Bureau for free. Browse evidence previews as a Cadet, or subscribe as an Analyst to access the full evidence archive containing 26 items and collaborate with 1 other investigator on interactive evidence boards. You can ask questions, generate investigation boards, map connections between evidence, and contribute your own research.

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