The self-named Zodiac who terrorized Northern California in the late 1960s and early '70s has never been caught, despite extensive investigation by police and the press. The unidentified killer claimed responsibility for 37 murders in taunting letters to newspapers, although only seven were confirmed as his work. Zodiac's letters included four cryptograms, of which just one has been deciphered. Only one suspect, Arthur Leigh Allen, was ever served with a search warrant, but police found no conclusive evidence. The Zodiac letters stopped coming in the late '70s; Allen died in 1992. The case has been declared inactive, although it is periodically reopened as new (and thus far implausible) evidence comes forward. The case was given screen immortality in the 2007 David Fincher movie Zodiac but Fincher didn't solve it either.
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