Police composite sketch of the zodiac circa 1969
The zodiac was a serial killer who operated in northern California during the late 1960's and early 1970's. The killers identity remains unknown. The Zodiac murdered victims in, Vallejo, Benicia, Lake Berryessa, and San Francisco between December of 1968 and October of 1969.Four men and three women between age 16-29 were targeted. The killer originated the name "Zodiac" in a series of taunting letters sent to the Bay Area press. These letters included four cryptograms. Of the four cryptograms sent, only one has been definitively solved.
Note: Source Wikipedia.