Zodiac Killer’s 51-Year Cipher

The Zodiac Killer mailed a series of cryptic messages to newspapers during his murder spree in Northern California between 1968 and 1969, taunting investigators and the public. One of those messages, known as the 340 cipher, remained unsolved for more than five decades despite intense study by professional codebreakers and investigators. In December 2020, three amateur cryptography enthusiasts, David Oranchak, Sam Blake, and Jarl Van Eycke, finally cracked the code using a combination of software tools and persistence. Their solution revealed a chilling message in which the serial killer mocked police and claimed he was not afraid of execution. Though it solved one of the most famous puzzles connected to the Zodiac serial killer, the killer’s true identity remains unknown.

Previous Fact Next Fact