Please note that the content of this book primarily consists of articles available from Wikipedia or other free sources online. ZOdiac is a non-fiction book written by Robert Graysmith about the unsolved serial murders committed by the "Zodiac Killer" in San Francisco in the late 1960s and early 1970s. SInce its initial release in 1986, Zodiac has sold 4 million copies worldwide. GRaysmith was a cartoonist for the San Francisco Chronicle and later also wrote Zodiac Unmasked.THis book depicts the killings and actions of the Zodiac who was active in the 1960s and 70s in California. IT details Graysmith''s collections of Zodiac evidence and material and eventually names Arthur Leigh Allen as the man Graysmith believes to be the killer. HE pinpoints evidence that shows many different reasons why he believes Allen is the Zodiac. THere was some evidence that pointed away from Allen as the killer, but there was a lot more evidence according to Graysmith, that points toward Allen as the killer. GRaysmith got help from police departments that were in the jurisdictions of the murders, especially from Inspector Dave Toschi from the San Francisco Police Department who was assigned to the Zodiac case.