Field report

The Zodiac Killer Ciphers

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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