The Zodiac Killer (also known by the pseudonym The Zodiac) is an unidentified serial killer who murdered at least five people in the San Francisco Bay Area between December 1968 and October 1969. The Zodiac attacked three couples and a cab driver in Benicia, Vallejo, unincorporated Napa County, and the city of San Francisco. Two of the Zodiac's seven victims survived.
In a series of letters mailed to Bay Area newspapers, the Zodiac took credit for the murders, described details known only to police, threatened bombings and more murders if the newspapers did not print his letters, and included cryptograms with his correspondence. Two of the Zodiac's four cryptograms were decrypted in 1969 and 2020, and the other two remain unsolved. The Zodiac's last letter was received by the San Francisco Chronicle in 1974. In the letter, the Zodiac claimed to have killed 37 people.
Despite several theories about the Zodiac's true identity, the only suspect police named was Arthur Leigh Allen, a former elementary school teacher and convicted sex offender who died in 1992. The Zodiac's murders, cryptograms, and letters to newspapers have made the case one of the most famous unsolved cases in American history. The Zodiac has become a fixture of popular culture, and the search for his identity continues to be pursued by amateur detectives all over the world.
In 2004, the San Francisco Police Department marked the case "inactive", but subsequently re-opened the case in 2006. The California Department of Justice, the Federal Bureau of Investigation, the city of Vallejo, and the Napa and Solano county sheriffs maintain the case status as "open".
Police and investigators concur The Zodiac attacked seven people on four occasions in California. Five victims died; two survived:
David Arthur Faraday (17) and Betty Lou Jensen (16) were shot and killed on December 20, 1968, on Lake Herman Road in Benicia.
Michael Renault Mageau (19) and Darlene Elizabeth Ferrin (22) were shot around midnight between July 4 and 5, 1969, in the parking lot of Blue Rock Springs Park in Vallejo. Mageau survived the attack; Ferrin died at Kaiser Foundation Hospital.
Bryan Calvin Hartnell (20) and Cecelia Ann Shepard (22) were stabbed on September 27, 1969, at Lake Berryessa in Napa County. Hartnell survived; Shepard died from her injuries on September 29 at Queen of the Valley Hospital.
Paul Lee Stine (29) was shot and killed on October 11, 1969, in the Presidio Heights neighborhood of San Francisco.
From 1969 to 1974, the Zodiac sent over twenty letters to newspapers, police, Chronicle writer Paul Avery, and attorney Melvin Belli. In the first sentence of the third letter, the writer identified himself as, "This is The Zodiac speaking," and signed all his letters with a symbol resembling the crosshairs of a gunsight: . Four of the mailings included cryptograms; only two have been solved. The letters were postmarked in San Francisco and Pleasanton.
The Zodiac's confirmed correspondence with date, recipient, and incipit:
July 31st 1969: San Francisco Chronicle, San Francisco Examiner, and Vallejo Times. One-third of "Z408 cryptogram" enclosed with each letter. "I am the killer of the 2 teenagers last Christmass..."
August 4th 1969: Examiner. "This is the Zodiac speaking."
October 13th 1969: Chronicle. Swatch of Paul Stine's shirt. "I am the murderer of the taxi driver..."
November 8th 1969: Chronicle. "Z340 cryptogram." The "Dripping Pen" card. "I though you would need a good laugh..."
November 9th 1969: Chronicle. Bomb diagram. "...I have killed 7 people".
December 20th 1969: Melvin Belli. Swatch of Stine's shirt. "...happy Christmass."
April 20th 1970: Chronicle. "Z13 cryptogram." "My name is..."