Field report
The Zodiac Killer Ciphers
Overview
Unidentified serial killer who operated in California in the late 1960s and early 1970s. Sent taunting letters and ciphers to the press.
Investigation
Only one of the four ciphers sent by the killer has been definitively solved. The identity of the Zodiac Killer remains unknown.
Why it matters
One of America's most infamous unsolved serial killer cases, highlighting the chilling nature of anonymous threats and the enduring quest for justice.
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