These are just three examples. But for now, we will examine the long-held belief that the Zodiac Killer was referencing the "The Most Dangerous Game" by Richard Connell (first published on January 19th 1924) when he encoded the wording "I like killing people because it is so much fun. It is more fun than killing wild game in the forest because man is the most dangerous animal of all". The Richard Connell short story was later adapted for screenplay, most notably in the 1932 RKO Pictures version starring Joel McCrea and Leslie Banks. While "The Most Dangerous Game" may be the inspiration for the Zodiac Killer's choice of words in the 408 cipher, did another more recent movie inspire him to find "The Most Dangerous Game".
The Zodiac Killer's July 31st 1969 letters to the San Francisco Chronicle, San Francisco Examiner and Vallejo Times-Herald opened up with the wording "I am the killer of the 2 teen-agers last Christmass at Lake Herman" and "This is the murderer of the 2 teenagers last Christmass at Lake Herman". It was the double murder of David Faraday and Betty Lou Jensen on December 20th 1968 (with the Zodiac claiming a "pencil flashlight" attachment to his gun) that most resembled a killer hunting game, as referenced in the 408 cipher. This was the crime that began the canonical Zodiac murders.
RAMPAGE (1963)- THE MOVIE BEHIND THE 408 CIPHER & JULY 31ST LETTERS