The Unsolved Ciphers of the Zodiac Killer

Vision in memorial di 7:29 PM

On October 27, 1970 the Halloween card pictured here was sent by the 'Zodiac Killer' to Paul Avery, a reporter for the San Francisco Chronicle. Pretty scary, huh?

The memories of this year's Halloween may be fading, but it makes sense to be wary of any suspicious person following you and perhaps not go out there alone after dark.

If you were to forget these words of warning, the thought of the Zodiac Killer might serve as a reminder. The Zodiac Killer was arguably the most devious murderer in the history of American serial killers.

He claimed to have murdered 37 people in his letters to the San Francisco Chronicle. He has not been caught yet. Maybe he is even still alive, living next door or a few blocks away from you, planning to make a return with another heinous crime.

This letter was another piece of evidence. It was found in December, 1966 in Riverside City College Library, California.

This most mysterious story began on the night of December 20, 1968. A motorist discovered the dead bodies of two teenagers, Betty Lou Jensen and David Faraday, on a dark road near Benicia, California. The investigation gave up no clues.

Then, while people were trying to come to terms with of the shocking news, a mysterious call was received at Vallejo Police Department less than month later. On July 4, 1969, right after midnight, an unknown caller reported another horrible incident that took place in a public park some miles away. This time a young couple had been murdered. In a monotone voice, the caller claimed responsibility for the slayings. This is believed to be the first call made by the Zodiac Killer himself.

Zodiac Logo

From this point on, the killer started communicating via letters and greetings cards. Each of these messages was concluded with the crossed-circle design pictured above. Later it became known as the Zodiac signature. These letters as well as some coded messages were sent by the killer to different, well-known newspapers, including the San Francisco Examiner and the Vallejo Times Herald.

It was the Zodiac Killer’s demand that the cryptograms be published on each newspaper's front page by August 1, 1969 or else other murders would take place.

This is a very important piece of the ‘340-symbol cipher code’ mailed in November, 1969 to the San Francisco Chronicle. The code has still not been cracked. The letter also included one third of a cryptogram.

By sending a cipher code as well as a teasing cipher key, the Zodiac Killer was always trying to puzzle the investigators. Even after almost 40 years, most of the cryptograms are still unsolved.

Most of the letters contained threats and the killer’s long descriptions of his fantasies. He demanded that the people of the Bay Area wore “some nice Zodiac butons” [sic] – the crossed circle symbol – and that failure to do so would result in their death.

Top secret letter, Postmarked: May 2, 1978. Sent to: KHJ-TV, Los Angeles, California

'Exorcist letter', mailed on January 29, 1974 to the San Francisco Chronicle.

For years, the case of Zodiac Killer has been the subject of debate and controversy. Many people are still trying to solve the case and decode the ciphers. The information is there in the form of photographs, videos, letters, sketches, police reports as well as another top secret letter. But the investigators are no less in the dark.

As Wikipedia points out, the Zodiac Killer's crimes, as well as the letters and cryptograms sent to police and newspapers, have inspired many movies, novels and TV programs, not to mention other serial killers. Some of the famous movies are: Dirty Harry, The Zodiac Killer, Zodiac Killer, Zodiac, The Zodiac, and The Exorcist III.

A sketch of the Zodiac killer based on witness testimonies

There were many suspects in the case. Arthur Lee Allen, one of them, died in 1992. Among the other suspects was a man named Jack Tarrance, also now dead. However there is always the possibility that the Zodiac Killer is still out there and does not want his work to be credited to someone else. He clearly liked the attention.

Maybe he is dead by now; but maybe he is still out there, watching the world, while the world tries to solve his cryptograms and the mystery of his unforgettable crimes.

Though searching for the Zodiac Killer has become a part-time venture for professional detectives today, for amateurs, it is still a full-time obsession...

Take caution if you sense someone following you...