50 years ago, the Zodiac sent a greeting card with a cipher consisting of 340 symbols. Today, the cipher remains one of the most baffling clues in true crime history. Computer programmer and Zodiac cipher expert David Oranchak (ZodiacKillerCiphers.com) talks about the enduring mystery of the "Z340."

Click here to view the Zodiac's 340 cipher, the original envelope, and the "dripping pen" greeting card with the Zodiac's message inside at the ZodiacKillerFACTS Document Gallery.

Written and produced by Michael Butterfield for ZodiacKillerFacts.com / Copyright 2019

Voice of "The Zodiac" by John Knight 

All music licensed and used by permission. “Run and Hide” and “Frozen Orb” composed and produced by Jens Kiilstofte. “Ghost” and “Creepy Piano Loop” composed and produced by JM Scherf. “Growing Shadows” created by Myuu. Provided by Mediacharge.

Link: http://www.zodiackillerfacts.com/gallery/thumbnails.php?album=8