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Zodiac Killer

The Zodiac Killer was an unidentified American serial killer who murdered at least five people in Northern California between 1968 and 1969.

By Ethan Anderson| Reviewed by Olivia Bennett, Standards & Fact-Checking Lead| Updated July 26, 2026|2 min read| Fact-checked

The Zodiac Killer was an unidentified American serial killer who murdered at least five people in Northern California between 1968 and 1969. The killer sent taunting letters and coded messages to newspapers and police, but the case has never been solved and the person’s real identity remains unknown.

Background

The Zodiac Killer is the name used for an unidentified serial murderer active in Northern California in the late 1960s. The killer became notorious for publicity-seeking communications sent to the press and police.

Confirmed crimes

Authorities have linked the Zodiac Killer to at least five confirmed murders and two attempted murders. The case is commonly discussed as one of the most famous unsolved serial murder investigations in the United States.

Letters and ciphers

The Zodiac sent letters containing threats, references to astrology, and coded messages, or ciphers, to newspapers and law enforcement. Some ciphers have been solved, while others have remained undeciphered or only partially interpreted.

Investigation and suspects

The Zodiac Killer was never officially identified, although several suspects have been proposed over the years. Authorities have not confirmed claims made by private investigators or later theories about the killer’s identity.

Key facts

  • The Zodiac Killer is believed to have murdered at least five people in the San Francisco Bay Area and surrounding parts of Northern California.
  • The confirmed attacks occurred between 1968 and 1969.
  • The killer mailed letters and cryptograms to newspapers and law enforcement, often using the name "Zodiac".
  • The case remains unsolved, and authorities have said the killer has never been caught.
  • No real name has been verified by law enforcement as the Zodiac Killer’s identity.

Frequently asked questions

Who is the Zodiac Killer?
The Zodiac Killer was an unidentified serial killer who murdered at least five people in Northern California and sent taunting letters and ciphers to the press and police.
How many people did the Zodiac Killer kill?
Authorities have confirmed at least five murders, and the killer also attempted to murder two others.
Was the Zodiac Killer ever caught?
No. The case remains unsolved, and the Zodiac Killer has never been officially identified or caught.
What are the Zodiac Killer's ciphers?
They are coded messages the killer mailed to newspapers and police. Some have been solved, but others remained unsolved for years or have not revealed the killer’s identity.
When did the Zodiac Killer operate?
The confirmed crimes took place between 1968 and 1969 in Northern California.
What is the Zodiac Killer's real name?
The real name has never been verified by law enforcement and remains unknown.

References

  1. Encyclopaedia Britannicahttps://www.britannica.com/biography/Zodiac-killer
    Supports: Unidentified serial killer; at least five victims; active in northern California between 1968 and 1969; never caught.
  2. BBC Newshttps://www.bbc.com/news/world-us-canada-55285805
    Supports: The Zodiac Killer murdered five people in the late 1960s; letters and ciphers; killer was never caught; claim of 37 victims.
  3. NBC Newshttps://www.nbcnews.com/news/us-news/case-remains-open-fbi-refutes-claim-zodiac-killer-case-solved-n1281002
    Supports: FBI said the case remains open; at least five deaths in Northern California from 1968 to 1969; taunting letters and cryptograms; never caught.
  4. Peoplehttps://www.people.com/why-was-the-zodiac-killer-never-caught-8732010
    Supports: Confirmed murders and attempted murders; ongoing unsolved status; case remains open; real identity still a mystery.
  5. Wikipediahttps://www.wiki.org/wiki/Zodiac_Killer
    Supports: Background on alleged ciphers, victims, and chronology; used cautiously as a secondary reference.