THE 340 CIPHER WAS CRACKED ON DECEMBER 3RD 2020 BY DAVE ORANCHAK, SAM BLAKE AND JARL VAN EYCKE, SO THIS EARLIER ARTICLE SHOULD BE VIEWED IN RESPECT TO RECENT DEVELOPMENTS.

In the last article 'The 340 Cipher-Trick or Treat?' we attempted to show how the Zodiac Killer used two xeroxed keys in the 1990 'American Greetings' card to intimate that the 340 cipher should be inverted or flipped, in order to begin the message with 'This is the Zodiac speaking'. The 'Halloween' card intersecting "sorry no cipher" key, was also used to show how Paradice and Slaves was pivotal to the design of the 340 cipher. But another cryptic communication arrived just 22 days before the 'Halloween' card, on October 5th 1970, entitled the '13 Hole' postcard. The Zodiac Killer could easily have drawn or photographed the keys in the 'American Greetings' card, but opted to xerox or photocopy them. The same could be said of "sorry no cipher", which he could easily have written once. This led to the notion that these two deliberate choices had a meaning or message. This brings us to the '13 Hole' postcard.

Just like the 'American Greetings' card, why does the Zodiac Killer punch 13 holes through the fabric of this card in a 10:3 configuration, rather than just fill in 13 circles like his ciphers? On the address side these holes can be found on the extreme left of the card, which then obviously switch position when the card is turned over. It can also be noted that the text at the bottom left of the card is also flipped over. It read ​"There are reports city police pig cops are closeing in on me. Fk I'm crackproof. What is the price tag now?" The 'American Greetings' card, it was suggested, used two keys to infer the 340 cipher code should be flipped - the bottom row becoming the top row and vice versa - allowing one of only two prominent 'words' on the 340 to settle on the top row, to facilitate the opening message of 'This is the Zodiac speaking'. The second prominent word of 'Her' (that begins the cipher) would now be flipped to the bottom line of the 340. The '13 Hole' postcard gives us the first clue to suggest the likelihood of this being the case.

The Zodiac Killer punched 13 holes into the card with a hole punch, A keypunch is also a device for precisely punching holes into stiff paper cards at specific locations as determined by keys struck by a human operator. Or in computing, a mechanical device whose keys are pressed, individually or in combination, to punch holes in punched cards or paper tape that correspond to particular characters. Programs or wording can be encoded onto a punched card. Did the Zodiac Killer encode a message in a 10:3 configuration using these punched holes, that would not only take 'Her' to the bottom line of the 340 cipher, but use the identical wording on the envelope of the 'Halloween' card to achieve it?    

The message the Zodiac Killer may have wanted to convey, was that "sorry no cipher" hypothetically written on the address side of the '13 Hole' postcard, would not only separate the word 'Her', but it would effectively be inverted or flipped over to the other side when the postcard was turned. The flipped text containing "Fk I'm crackproof" testament to the fact we have a 'Flipped key', despite the boast of Zodiac claiming he was "crackproof" because of it  The 'Her' has now switched sides, thereby giving us our third key to the workings of the 340 cipher. The Zodiac Killer used two keys in the 'American Greetings' card to flip the 340 cipher, and a hole punch here to project the same message. He even added a red crucifix with the number 13 above, to highlight the connection to the 'big thirteen' letters of paradice and slaves on the 'Halloween' card he was soon to mail. Inversion was at the heart of these three communications, using keys in all instances - and all pointing to a 340 cipher that should be turned on its head. 

THE 340 CIPHER WAS CRACKED ON DECEMBER 3RD 2020 BY DAVE ORANCHAK, SAM BLAKE AND JARL VAN EYCKE, SO THIS EARLIER ARTICLE SHOULD BE VIEWED IN RESPECT TO RECENT DEVELOPMENTS.

The first section of this article is a refresher, before we incorporate the rarely mentioned 'American Greetings' card, postmarked December 1990. This card, devoid of any handwriting on the card inner, was the sister communication to the Halloween card, also beginning with "From your secret pal", but contained a photocopy or xerox of two keys that have mystified as to their meaning. We will attempt to combine this communication with the Halloween card and explain its relevance to the Zodiac Killer's unsolved 340 cipher. As always, this analysis must be treated with a healthy dose of skepticism.
  
So firstly, I would like to press home the notion that the Zodiac Killer's 340 cipher was nothing more than a ruse, designed to stick two fingers up to the challenge laid down by Professor D.C.B. Marsh of the American Cryptogram Association (ACA) on October 22nd 1969, when he "invited Zodiac to send The American Cryptogram Association a cipher code - however complicated - which will truly and honestly include his name." The Zodiac Killer would eventually reveal the workings of the 340 cipher just over a year later when he mailed the rather cryptic Halloween card on October 27th 1970, revealing the trick, not treat, he had perpetrated on his challengers. The killer couldn't have been any more obvious when he actually wrote "sorry no cipher" on the envelope inner.

​In 1970, the Zodiac Killer mailed the Dragon card, the Kathleen Johns letter, the Little List letter and the '13 Hole' postcard, none of which stated the glaringly obvious, that he hadn't sent a cipher with any of them. Why would he then apologize for not sending a cipher with the Halloween card when it was patently apparent upon opening the communication? Even if he had wanted to apologize, why didn't the Zodiac Killer just write "sorry no cipher"? The fact he wrote it twice in the form of two intersecting lines suggests this design was created for a purpose. The only other intersecting text on the entire card were the words "Paradice" and "Slaves", so was the author of the Halloween card telling us that something he had created wasn't a cipher, only the intersecting words of "Paradice" and "Slaves"? If we could find "Paradice" and "Slaves" intersecting each other in any previously unsolved cipher, structured in similar fashion to "sorry no cipher", then this should be a strong argument to the meaning behind the Halloween card. We need to find "Slaves" running horizontally, preferably at the center of the 340 cipher and bisect it with the word "Paradice" (hopefully beginning with the letter "P" somewhere at the top of the cipher along the 9th column). 

Fortunately, nine characters along the top row is the letter "P". Then we must travel downwards 17 characters in order to create two lines of equal length and find the "E" of "Paradice". This will now be represented by the character "<".  We now have two lines of 17 characters, bisected by a "+" sign (the center of the crosshairs). The 'wings' of the crosshairs are represented by two dashes, situated in columns 1 and 17. These represent the two "S" letters of "Slaves". This is all very convenient. 

​There are only two identical characters (the "+" sign) in the 9th column along the first 10 rows, and we know the letter "A" is center of the bisecting "Paradice" and "Slaves" on the Halloween card. It is then a simple task of placing the "R" of "Paradice" and "LV" of "Slaves" into position, to exactly mirror the Halloween card formation. It is then not difficult to find the word "By" in all four quadrants of the 340 cipher, again mirroring the Halloween card. See here for visual. 

The second clue may have also come from the envelope, when the Zodiac Killer underlined the 'LAV' of the misspelled Paul Avery on the address side. The three letters 'LAV' bisected the center point of the 340 cipher. What are the odds of "sorry no cipher" mimicking the "Paradice" and "Slaves" formation on the Halloween card, which then mimicked the 340 cipher, along with  the three alphabetical letters 'LAV' being integral to both. 

The Zodiac Killer knew that the first anniversary of his 340 cipher being unsolved was fast approaching, and this Halloween opportunity of revealing his trick to the world, albeit wrapped in another cryptic message, was simply too much to resist.

The words "Paradice" and "Slaves" were decoded in the 408 cipher and featured prominently in the Halloween card, so what are the chances they were an integral part in the design of the 340 cipher as well? So much so, they may have formed crosshairs, bisecting the cipher at its midpoint? If none of the above was an intentional creation by Zodiac and it all fell out by accident, then he is certainly one hell of a fortunate designer. 

In the words of Thomas Horan, the 340 cipher was certainly the "Great Zodiac Killer Hoax of 1969".

When the Zodiac Killer mailed his trinity of July 31st 1969 communications he withheld his identity or pseudonym, but beginning on August 4th 1969 with his 'Debut of Zodiac' letter through to his March 13th 1971 'Los Angeles' letter, every single letter the Zodiac Killer mailed began with "This is the Zodiac Speaking" (excluding cards). So why should the 340 cipher message be any different - which was effectively a letter within a card. 

We do not know if the Zodiac Killer was responsible for the mailing of the 'American Greetings' card, but for the purpose of this argument we will assume that he was. On the left is the photocopy of the two keys that arrived with the communication. The two keys must have had some meaning to the sender - but what? It is clear that the sender could have photographed the keys, drawn two keys or even pasted two 'newspaper keys' onto the card, but made the deliberate choice of photocopying two keys for a reason. The act of the photocopying, one would like to believe, was done to convey a message.

A negative photocopy inverts the colors of the document when creating a photocopy, resulting in letters that appear white on a black background instead of black on a white background. Negative photocopies of old or faded documents sometimes produce documents which have better focus and are easier to read and study. Wikipedia. ​To invert something is to put upside down or in the opposite position, order, or arrangement. Synonyms of invert, are to turn upside down, upturn, upend, turn around, turn about, turn inside out, turn back to front, reverse, flip (over) or transpose. Therefore, was the designer of the 'American Greetings' card hinting that we should "invert the key" or "flip the key". In other words, the key to the 340 cipher is to "invert" or "flip" it on its head in order to read it. The "sorry no cipher" arrangement on the Halloween card envelope was equated with "Paradice" and "Slaves", but could have been written with the 'vertical' "sorry no cipher" running downwards. Could this imply that "Paradice" was meant to be flipped on the 340 cipher, running from bottom to top?  

If we go to David Oranchak's excellent Zodiac Killer Ciphers website and employ his 340 cipher Webtoy using the 'flip vertically' function, the 20th and 1st rows are flipped, the 19th and 2nd rows are flipped, and so forth. In essence, the bottom line now becomes the top line. The "Zodiac" he gave us on the 20th line is now in the perfect position on the top line to open up this communication or cipher with the infamous words "This is the Zodiac Speaking", just like every other letter from August 1969 to March 1971. 

The correspondence before the Halloween card was the October 5th 1970  '13 Hole' postcard. It too contained a cross and flipped text, stating "There are reports city police pig cops are closeing in on me. Fk I'm crackproof. What is the price tag now?"

Wouldn't it be nice if "Fk" meant "Flipped key" as well, and the '13 Hole' postcard was the third member of the trinity of solutions to the Zodiac Killer's unbreakable 340 cipher.

It would be befitting that the Zodiac Killer's last correspondence may possibly be the 'Eureka' card mailed in the December of 1990, considering the last major work of Edgar Allan Poe was the non-fiction offering Eureka: A Prose Poem. "Adapted from a lecture he had presented, Eureka describes Poe's intuitive conception of the nature of the universe with no antecedent scientific work done to reach his conclusions. He also discusses man's relationship with God, whom he compares to an author. Similar to his theories on a good short story, Poe believes the universe is a self-contained, closed system. In coming to his conclusions, Poe uses ratiocination as a literary device, through his character C. Auguste Dupin, as if Poe himself were a detective solving the mystery of the universe. Eureka, then, is the culmination of Poe's interest in capturing truth through language, an extension of his interest in cryptography. Some modern critics believe Eureka is the key to deciphering meaning in all Poe's fiction, that all his works involve similar theories". Wikipedia. Strange therefore, that the Christmas card possibly engineered by Zodiac should contain a cryptic message in the form of photocopied keys mailed from Eureka, California.

This is not the only time that Edgar Allan Poe may have played a part in a cryptic message mailed by the Zodiac Killer. It could have been the essay A Few Words on Secret Writing that inspired the creation of the 13-Symbol cipher mailed on April 20th 1970 by the Bay Area murderer. A cipher that could have been devised sometime between October 22nd 1969 and November 8th 1969, and belatedly mailed by the killer some 6 months later, with the accompanying text about the murder of San Francisco police officer Brian McDonnell on February 16th 1970.

Michael Cole wrote an excellent article entitled "My Name Is" Cipher Motivation that suggested the Zodiac Killer likely drew his inspiration for the 13 -Symbol cipher from an October 22nd 1969 newspaper article by Will Stevens, which laid down a challenge to the Zodiac Killer from the president of the American Cryptogram Association (ACA), Professor D.C.B. Marsh, to reveal his name. Apparently, several months later the killer duly obliged by opening his correspondence with the line "This is the Zodiac speaking. By the way have you cracked the last cipher I sent you. My name is...." He followed this by placing 13 characters underneath, widely considered to be the Zodiac Killer offering us his name. 

It could be argued that this cipher was not only created because of the newspaper article, but designed based on what was contained within the article - in particular the works of Edgar Allan Poe. This would be right up Zodiac's alley, devising a cipher based in the text of the newspaper article. Here is an excerpt: Dr Marsh told the Examiner today: "The killer wouldn't dare, as he claimed in letters to the newspapers, to reveal his name in the cipher to established cryptogram experts. He knows, to quote Edgar Allen Poe, that any cipher created by man can be solved by man. Zodiac has not told the truth in his cipher messages to the Examiner, the Chronicle and the Vallejo Times-Herald. Zodiac has not done this, because to tell the complete truth in relation to his name-in cipher code-would lead to his capture. I invite Zodiac to send The American Cryptogram Association a cipher code, which will truly and honestly include his name". We can see in the Edgar Allan Poe offering of  A Few Words on Secret Writing, that the very beginning of the essay shows the alphabet being split into two halves of thirteen letters:

"Were two individuals, totally unpractised in cryptography, desirous of holding by letter a correspondence which should be unintelligible to all but themselves, it is most probable that they would at once think of a peculiar alphabet, to which each should have a key. At first it would, perhaps, be arranged that a should stand for z, b for y, c for x, d for w, &c. &c.; that is to say, the order of the letters would be reversed. Upon second thoughts, this arrangement appearing too obvious, a more complex mode would be adopted. The first thirteen letters might be written beneath the last thirteen, thus:
n o p q r s t u v w x y z
a b c d e f g h i j k I m; and, so placed, a might stand for n and n for a, o for b and b for a, &c. &c. This, again, having an air of regularity which might be fathomed, the key alphabet might be constructed absolutely at random".

Quite fortunate that the Zodiac Killer, after possibly reading this newspaper article, should then create a cipher of 13 characters beginning with an A (the first letter of the alphabet) and ending with an M (the 13th letter of the alphabet), just like Edgar Allan Poe's construction in his essay A few Words on Secret Writing. 

Throughout the newspaper article Professor D.C.B. Marsh is urging the Zodiac Killer to give his name, which clearly the Zodiac wasn't going to achieve with any reasonable possibility of decryption, but he may have played a game with D.C.B. Marsh by offering us another cryptic message within the cipher. We contended previously that the 340 cipher and 13-Symbol cipher could possibly have been created at the same time because of the interconnectivity between the two. The name Zodiac appeared to be numerically carried forward from the 20th line of the 340 to the 13-Symbol cipher in the form of three circled 8's. This was achieved by placing the correct spelling of Zodiac alongside the 'near Zodiac' and numerically counting the difference between the columns. This produced perfect numerical symmetry, as did placing A to M (half the alphabet) alongside the 13- Symbol cipher. For this to be achieved, it was argued the two ciphers must have been created with each in mind, and therefore both crafted at a similar time. See image here for explanation.
 
"In Christian numerology, the number 888 represents Jesus, or sometimes more specifically Christ the Redeemer. This representation may be justified either through gematria, by counting the letter values of the Greek transliteration of Jesus' name, or as an opposing value to 666, the number of the beast". Wikipedia.
Curiously, if you visit the English gematria site here and enter Edgar Allan Poe into the calculator, 666 is achieved.    
​Was the Zodiac Killer playing games, giving us the name Jesus in the form of a numerical value and depicting himself as the savior of souls for the afterlife?

Professor D.C.B. Marsh attempted to coerce the Zodiac into giving us his name by stroking his ego, therefore it seemed rather unusual that every alphabetical letter within the 13-Symbol cipher apart from one, could be found in the word NAME. The Zodiac Killer gave us A twice, M twice, N twice and E once. The only exception was the letter K - the only letter the Zodiac Killer scrubbed out in the 340 cipher. Removing this from the 13-Symbol cipher only leaves us with letters contained in the word NAME.

The creation of these two ciphers together is a plausible explanation for a correlation between the two, with the inspiration of Edgar Allan Poe in the construction of the 13-Symbol cipher, based upon splitting the alphabet down its center, was ultimately born from the article by Will Stevens. ​Edgar Allen Poe stated that "any cipher created by man can be solved by man". Could it be claimed that any cipher created by Zodiac can be solved by Edgar Allan Poe?

The last confirmed correspondence by the Zodiac Killer was the 'Exorcist' letter mailed on January 29th 1974, making the 1990 'American Greetings' or 'Eureka' card seem distant from the activities of the Bay Area murderer. We will therefore look at Unabomber Ted Kaczynski, whose known criminal activities were committed between 1978 and 1995. This will be working on the hypothesis that the Eureka 'Secret Pal' card was chosen separately and independently from the Zodiac Killer's 'Halloween' card mailed to the San Francisco Chronicle on October 27th 1970, twenty years previously. It could have been sent 'piggybacking' on the Zodiac communications, but after two decades it is more likely a case of coincidence.

There is an excellent thread discussing this Christmas card on the Zodiac Killer Site forum, but here we would like to approach the 'Eureka' card from a more simplistic angle and the reasoning behind the xeroxed or photocopied keys contained within the communication.

The wording on the card exterior read; "FROM YOUR SECRET PAL CAN'T GUESS WHO I AM YET? WELL, LOOK INSIDE AND YOU'LL FIND OUT..." and once opened it revealed: "...THAT I'M GONNA KEEP YOU GUESSIN'! HAPPY HOLIDAYS, ANYWAY".  The suggestion, is that once the card is opened it will reveal the identity of its author - and although there is no written message within the Christmas card - there are two photocopied keys. One would therefore like to believe, that this is the clue to the author's identity in the form of an image. Here is a manufactured image of how the presentation may have looked before a negative was produced. 

Many theories have been presented in respect to the image on the left, including the keys being arranged to mimic Groucho Marx smoking a cigar (when viewed upside down) and a play on the words "keys" and "chain". A Unazod article entitled 'A New Zodiac Missive' shows the writing on the envelope of the 'Eureka' card in comparison to a letter mailed to Mrs Irene Preston from Ted Kaczynski in the December of 1990. It is a compelling comparison. However, is there a more simplistic answer to the identity of the author using the image mailed to the San Francisco Chronicle.

"Theodore John Kaczynski born May 22, 1942), also known as the Unabomber, is an American domestic terrorist. A mathematics prodigy, he abandoned an academic career in 1969 to pursue a primitive lifestyle. Then between 1978 and 1995 he killed three people, and injured 23 others, in a nationwide bombing campaign targeting those involved with modern technology, in an attempt to start a revolution. In conjunction, he issued a social critique opposing industrialization and advancing a nature-centered form of anarchism. The initial 1978 bombing was followed by bombs sent to airline officials, and in 1979 a bomb was placed in the cargo hold of American Airlines Flight 444, a Boeing 727 flying from Chicago to Washington, D.C. A faulty timing mechanism prevented the bomb from exploding, but it released smoke, which forced an emergency landing. Authorities said it had enough power to "obliterate the plane" had it exploded. As bombing an airliner is a federal crime, the Federal Bureau of Investigation became involved in the case, designating it UNABOM for UNiversity and Airline BOMber. (U.S. Postal Inspectors, who initially had the case, labeled the suspect the "Junkyard Bomber" because of the material used to make the mail bombs. In 1979, an FBI-led task force that included the ATF and U.S. Postal Inspection Service was formed. The task force grew to more than 150 full-time personnel, but minute analysis of recovered components of the bombs and the investigation into the lives of the victims proved of little use in identifying the suspect, who built his bombs primarily from scrap materials available almost anywhere. The victims, investigators later learned, were chosen irregularly from library research". Wikipedia.

​Could Ted Kaczynski have used a photocopying machine during this library research and mailed the 'Eureka' card to the San Francisco Chronicle in the December of 1990? Ted Kaczynski was later to send carbon copies of his 'Manifesto' to various publications: "Last June and July, the Unabomber mailed carbon copies of the 62-page, single-spaced manifesto to the New York Times, Washington Post, Penthouse magazine and Tom Tyler, a UC Berkeley psychology professor. Tyler appears to have received his copy as something of an afterthought by the bomber. His only known connection to the case is that he had been quoted in a Bay Area newspaper commenting on the behavior of the serial killer". Los Angeles Times.

​"Beginning in the 1970s, Kaczynski targeted universities and airlines, injuring 23 people and killing three. After a threat mailed to the San Francisco Chronicle in June 1995, the USPS scrambled to come up with a plan to inspect all air mail packages out of California. For six days, USPS did not accept packages or letters bigger than 12 ounces. The threat, Kaczynski later admitted through an anonymous letter to the New York Times, was a prank. He had played the system against itself—delivering anonymous taunts through the mail and disrupting the very mail-delivery system". The Atlantic. 

The 'Unabomber' Ted Kaczynski would either mail his explosive devices using the postal service or hand deliver - so were the USPS (United States Postal Service) keys xeroxed and mailed with the 'Eureka' card to the San Francisco Chronicle, as a form of taunting towards the authorities he so obviously railed against in a game of cat and mouse - and within the image a clue to his name using only two alphabetical letters. The etched writing on the keys of USPS DO NOT DUPLICATE could be considered ironic with regards to the xeroxed image supplied.   

Ted Kaczynski claimed his first main casualty, when John Hauser, a captain in the Air Force was partially blinded in one eye and lost four fingers when receiving a mailed bomb in 1985. Hugh Scrutton, who owned a California computer store, in 1985 became the first fatality of the bombing campaign, followed in 1994 by Thomas J Mosser, an advertising executive and Gilbert P Murray in 1995, president of a lobbyist timber industry group. 

​Earlier in Ted Kaczynski's bombing campaign, on June 10th 1980, Percy Wood, president of American Airlines opened a package containing a book called 'Ice Brothers' packed with explosives, from which he narrowly cheated death. The device was constructed using wood - the victim's last name was Wood and the return address was from a street named Ravenswood. ​Was Ted Kaczynski playing a game of words with investigators in his attempted murder of Percy Wood? Inside the chiseled out section of the book Ted Kaczynski had inserted a small piece of metal in which the letters "FC" had been punched into its face. These two alphabetical letters would be used throughout his bombing campaign to identify his work to authorities. "In all, 16 bombs—which injured 23 people and killed 3—were attributed to Kaczynski. While the devices varied widely through the years, all but the first few contained the initials "FC." Inside his bombs, certain parts carried the inscription "FC," which Kaczynski later asserted stood for "Freedom Club."

One of Kaczynski's tactics was leaving false clues in every bomb. He would deliberately make them hard to find to mislead investigators into thinking they had a clue. The first clue was a metal plate stamped with the initials "FC" hidden somewhere (usually in the pipe end cap) in every bomb. One false clue he left was a note in a bomb that did not detonate, which reads "Wu—It works! I told you it would—RV".  Wikipedia.

One can see that Ted Kaczynski was fond of leaving cryptic clues for investigators to find - so is it any great leap of faith that Ted Kaczynski would choose a Christmas card beginning with the lines "From your secret pal. Can't guess who I am yet?  Well look inside and you'll find out". So If Ted Kaczynski was to leave his name within the 'Eureka' card, then it had to be connected with the xeroxed image, and quite possibly may have been two initials in length. The image presented is that of 'Two Keys", the initials of which are TK, representing Ted Kaczynski. ​It's a simplistic analysis - but it's a simplistic image, with limited room for maneuver. 

The following article is an updated version of a previous post, expanded and covered in greater detail. It is not particularly a line of investigation that I subscribe to, but it attempts to compare the Zodiac Killer's Halloween Card mailed on October 27th 1970 with the Harper Lee novel 'To Kill a Mockingbird', published in 1960 and turned into a film in 1962 featuring Gregory Peck, Robert Duvall, Mary Badham and Phillip Alford. Set in the fictional town of Maycomb, the film explored the deep set racial undertones prevalent in American society, brought to the forefront, as lawyer Atticus Finch fought to defend a black man accused of rape in Alabama. The film won three Academy Awards including Best Picture and Best Actor. 

The most reclusive character in the film was Arthur "Boo" Radley, who went by the shortened version Boo Radley. The first thing to be noticed on the Halloween Card envelope is the misspelled name of the reporter Paul Avery to Paul Averly- which emphasizes the 'ley' section. On the inside of the card he places the word BOO in bold letters. Now we have two parts of our puzzle, "Boo" and "ley". To complete the name Boo Radley requires us to search for "Rad", which is not far away. It crosses the "LAV" of "SLAVES" on the Halloween Card paradice and slaves configuration - which rather fortunately was underlined on the envelope  containing the reporter's name. The Zodiac Killer may not have given us a cipher but had he given us "Boo Radley". 
 
Boo Radley was a much misunderstood character in the novel, feared and rumored upon by the local schoolchildren. He was described by Jem (brother of Scout Finch) as "6 1/2 feet tall... dined on all the raw squirrels and cats he could catch... you could never wash the blood off... there was a large scar that ran across his face... his eyes popped and he drooled most of the time".  In fact, Boo Radley's house and chicken yard backed onto Maycomb School. Funny that - I remember Arthur Leigh Allen slaughtered chickens and squirrels and was never far from schools - but coincidence aside - we shall move on.

The children feared the Radley House and garden, believing the trees were poisoned, however, in one such tree a knot-hole existed, that would ultimately bridge a friendship between Boo Radley, Scout and Jem. Periodically the reclusive Boo Radley would  place objects in the knot-hole for Scout and Jem to find. This was his outlet to the world. On various days the two children would find presents he had left - which included carved soap figures, a ball of twine, chewing gum, a broken pocket watch, an Indian medal, and an aluminium knife on a key chain - many deposited in pairs, one for each child. This was their 'Tree Treasure'. In fact, 'Tree Treasure' was one of the tracks created for the musical score accompanying the film, composed by Elmer Bernstein. Two other tracks on the musical score were titled  'Boo Who' and 'Peek-a-boo.'. What a coincidence. 

The Halloween Card had a knot-hole in the tree with the words "peek-a-boo" circled around it.. Peek-a-boo is the act of concealing ones face behind the hands or other object, before suddenly appearing back into view and uttering the words peek-a-boo. It can be seen in Wikipedia that many variations involve trees, similar to the depiction on the Halloween Card, where 'Hiding behind that tree' is added. See here. That eye was certainly hiding in the Halloween Card tree - was it not. Didn't the Zodiac Killer hide behind a tree at Lake Berryessa and hide his face behind a mask?. When he eventually came into view his identity was concealed. When the Halloween Card was removed from the envelope, it goaded us  with the introduction "I feel it in my bones, you ache to know my name, and so I'll clue you in" - and once opened it revealed the word "BOO". I know what your thinking "Boo Who."  Well, I had to squeeze it in.

The Eureka Card, mailed in the December of 1990 was the sister card to the Halloween Card, and was very similar in design. It too began with a message from our 'secret pal', yet this time it had a present from Zodiac - not an aluminium knife and pocket watch on a key chain - but a photocopy of a pair of keys on a key chain. 

In the novel Scout and Jem made a snowman, constructed with mud, then layered with snow - a theme many believe was suggestive to the racist overtones of the story. A snowman is depicted on the Eureka Card, with what appeas to be Groucho Marx imagery on the face. Jem and Scout built this snowman because of their dislike of a local resident down the street, but their father Atticus intervened and told the children to disguise it because it so resembled the local resident they were poking fun at. To placate their father, they placed Miss Maudie's hat on it. The resident they so disliked was called MR AVERY - now that is a coincidence, along with December 25th 1962 release date of the film in Los Angeles, California. The Eureka Card was mailed sometime in December and depicted a Christmas scene. Facing the snowman was a cute rabbit. I hope Arthur Leigh Allen didn't slaughter rabbits as well as chickens and squirrels. 

Incidentally, Scout and Jem went to a Halloween celebration. In the book on Chapter 28, the schoolchildren are encouraged to dress up in the local agricultural produce of Maycomb for the Halloween night pageant rather than go trick or treating. Scout is dressed as a piece of ham. While traveling home after the pageant, Jem and Scout are attacked by somebody and rescued by Boo Radley. As we all now know, Bob Ewell is later found dead under a tree with a knife stuck in him. It is curious that the skeleton on the Halloween Card is also wearing agricultural produce. Is that a pumpkin I see? And that tree keeps reappearing. 

Was this card based on the Lake Berryessa attack, or could the Zodiac have been peeking out, playing hide and seek in the Julius Khan playground in the Presidio. I feel something in my bones. Anyway, here ends the story. The only question left to ask is, have I now created a second piece of fiction?

The final confirmed letter mailed by the infamous Zodiac Killer to the San Francisco Chronicle on January 29th 1974 has been commonly referred to as the Exorcist Letter. This sixty-one word correspondence appeared to mock the 1973 movie The Exorcist, directed by William Friedkin and based on a novel by William Peter Blatty published in 1971, chronicling the demonic possession of a twelve-year-old girl, Regan MacNeil. William Peter Blatty spent long nights in a secluded Lake Tahoe cabin crafting images of good and evil, religion, faith and the afterlife, that would eventually go on to make movie history and court its fair share of controversy along the way. 

The letter is short, reminiscent of much of the Zodiac Killer's later contact with authorities, but as well as mentioning The Exorcist movie, the letter, in rather disjointed fashion, breaks into a Mikado recital once again, recalling memories of the Little List Letter mailed three and a half years previously on July 26th 1970. But this time the foreboding 'Tit Willow' seemed contemplatory in this context, possibly marking the end of the Zodiac reign - and to this day is still often quoted as the murderer's epitaph. The third and final section issued the usual threat of more murders, capped off with Asian style symbols in the form of a cryptic message. Like much of his later correspondence there is little substance here, but we will attempt to delve a little deeper into the Exorcist Letter and find any links that may be relevant or otherwise, as to why he wrote the letter in the first place. This is not a theory, just an examination into where the Zodiac Killer may have been drawing his inspiration.       

The Little List Letter mailed to the San Francisco Chronicle on July 26th 1970 heavily featured the Gilbert and Sullivan stage play, The Mikado. One section loosely quotes 'a more humane Mikado',  followed by the more extensive paraphrasing of Act 1 Part 5a, 'As some day it may happen'. The curious thing, is that the Zodiac Killer's version of the Little List mimics closer to the Groucho Marx version in the Bell Telephone Hour (1960) than the original Gilbert and Sullivan play. Visit here for the full audio collection: Gilbert Sullivan-The Mikado audio. A thread at the Zodiac Killer Site Forum also covers this topic in detail. Groucho Marx would possibly appear again, depicted in the American Greetings Card or Eureka Card, mailed by either the Zodiac or a copycat in the December of 1990.

The Eureka Card was reminiscent of the Halloween Card mailed some 20 years earlier. It begins with the words FROM YOUR SECRET PAL CAN'T GUESS WHO I AM YET?  WELL, LOOK INSIDE AND YOU'LL FIND OUT...  and once opened stated ... THAT I'M GONNA KEEP YOU GUESSIN'! HAPPY HOLIDAYS, ANYWAY. The scene portrayed on the Christmas card  was of a snowman disguised in a Groucho Marx style nose and glasses. In front of the snowman was a rabbit or hare apparently gazing up at the wintry scene. One cannot help thinking the Zodiac Killer chose his cards for a reason.

Another interesting connection was noted on viewing the Tom Hanson Zodiac movie from 1971, in that the killer wore a Groucho Marx style nose and glasses in one scene from the movie. View the scene and thread at ZodiacKiller.com. But this was not the only possible film connection to the Groucho Marx disguise featured on the 1990 Eureka Card.  

Terror Train was released in 1980, directed by Roger Spottiswoode and starring Jamie Lee Curtis, Ben Johnson and David Copperfield. During New Year celebrations at the students fraternity house Sigma Phi, a prank backfires on Kenny Hampson (Derek MacKinnion). Mentally scarred by the event, this forms the basis of revenge when the students responsible for the prank board a private train hosting a fancy dress party, exactly three years later. On boarding the train one of the students is stabbed, but his friends believing it is a prank, continue along unconcerned. The killer collects the victim's Groucho Marx mask, follows them onto the train and seeks his revenge, one by one. The movie was primarily a thriller/slasher, filmed in Canada from November 21st to December 23rd 1979 and released by Twentieth Century Fox in the October of 1980.

But can we connect Groucho Marx to the Exorcist Letter? Not directly, but by association. The Zodiac Killer described The Exorcist as, "the best satirical comedy that I have ever seen". Well, this may not be the case, however, the genesis of the movie may well have been born with the help of a comedy genius - that of Groucho Marx. The Exorcist author, William Peter Blatty, was a close friend of Groucho Marx, and there was an intention by Marx to dress as the priest Father Lankester Merrin from the movie and appear on the set of the Exorcist film, but due to scheduling matters the comedic entrance never materialized. But in one episode of the popular You Bet Your Life series, hosted by Groucho Marx, William Peter Blatty was a contestant and walked away with a prize of $10,000. When he was asked what he was going to do with the money, he stated he was to take some time off  to work on a novel. That novel was the acclaimed inspiration for the movie The Exorcist.  

Groucho Marx was a lifelong fan of the Gilbert and Sullivan operas, appearing as Ko-Ko in a production of the Mikado, on NBC's Bell Telephone Hour in 1960. He also recited Tit Willow in 1960 and on the Dick Cavett Show on March 20th 1970. Wikipedia. Therefore, Groucho Marx can be associated through the Little List Letter mailed on July 26th 1970, the Exorcist Letter on January 29th 1974 and the Eureka Card in the December of 1990. However, there is a little more background.

William Peter Blatty released a novel in 1966, entitled Twinkle,Twinkle Killer Kane. It achieved little commercial or critical acclaim. View accompaniment. The story centers on a psychiatrist, 'Killer Kane' (Hudson L Kane) and explores faith, humanity and irony. He enters a madhouse to determine if its residents, comprised of soldiers and astronauts are actually mad or just putting on an act. This results in extended interaction with resident Manfred Cutshaw on the concept of God. In the story Kane postulates "every man who has ever lived has been born with desire for perfect happiness. But unless there is an afterlife, fulfillment of this desire is a patent impossibility". It was to be later rewritten and published under the new title 'The Ninth Configuration' in 1980, attempting to explore the marginal line of sanity over insanity. It failed to inspire the public on its cinematic release.    

To Kill a Mockingbird, written by Harper Lee, was a hugely successful book published on July 11th 1960 and later adapted into a motion picture starring Gregory Peck two years later, portraying racial injustice and the innocence of youth from the backdrop of the fictional town of Maycomb, Alabama. This next section is not inferring the Zodiac drew any inspiration from this novel, however, it will outline some unusual coincidences between this work of fiction and two greeting cards mailed by the Zodiac, notably the October 27th 1970 'Halloween' card and the December 1990 'Eureka' or 'American Greetings' card.

​Kevin Robert Brooks noticed that the Asian characters at the foot of the 'Exorcist' letter could be rearranged to spell the words, 'To Kill'. These are obviously the first two words of this novel, but the 'Exorcist' letter also contained an extract from The Mikado about a bird, taken from Act II On a tree by a river- a little tom-tit in this case. 

To Kill a Mockingbird was widely used as an educational tool in many schools, in which one of the central characters was "Boo" Radley, a reclusive resident of Maycomb, who generated a constant source of suspicion and mystery from the local townsfolk, despite his later acts of disguised benevolence. Note BOO on the 'Halloween' card. He went by the name Boo Radley, but curiously his first name was Arthur. 

The alphabetical letters LAV letters are present together in the horizontal word SLAVES on the back of the card and underlined in the name Paul Averly on the envelope, but note the three letters at the intersection of the crossed PARADICE and SLAVES running vertically - they spell RAD,
The incorrect spelling of Paul Avery to Averly points towards LEY, to complete the character BOO RADLEY.

In the novel, a local resident by the name of Stephanie Crawford reported she was woken up one night and saw Boo Radley "looking straight through the window at her..... said his head was like a skull lookin' at her". On the tree around the knothole there are the words PEEK A BOO YOU ARE DOOMED.

The musical score to the original motion picture was composed by Elmer Bernstein. Three of the soundtracks are Creepy Caper/Peek-a-Boo, Boo Who and Tree Treasure. In the book, Tree Treasure was a hiding place in the knothole of a tree, where several items were found including a broken pocket watch, an aluminium knife and a ball of twine. These were placed there by Boo Radley for two local kids, Scout and Jem, to discover. The knothole in the tree represented Boo Radley's outlet to the world, and soon the children were to realize that Boo Radley was far from the monster he had been depicted. All the items he placed at intervals in the knothole came in pairs, except the twine - there were two packets of chewing gum, two polished coins, two miniatures of children, and the most interesting of all, was a knife and pocket watch, both on the same chain. Presumably two items, so Jem and Scout could have one each. The 'Eureka' card or 'American Greetings' card, mailed by the Zodiac Killer in 1990, was very similar to the 'Halloween' card in its design, both beginning with the phrase "From your secret pal". The 'Eureka' card included a photocopy, of not one, but a pair of keys on a chain. But who was the "secret pal" - the Zodiac Killer or Boo Radley?

​Incidentally, Scout and Jem build a snowman in the the Harper Lee novel, made initially from mud, but then layered with snow- a theme many believe is reflective of the racial overtones contained within the story. A snowman was depicted on the 'Eureka' card, with what appeared to be Groucho Marx imagery on the face. Jem and Scout created this snowman because of their dislike of a local resident down the street, much to the annoyance of their father Atticus Finch, who told the children to disguise it because it so resembled the local resident they were poking fun at. Their solution was to place Miss Maudie Atkinson's hat on it (she lived across the street from Atticus Finch and his family). The resident they so disliked was called MR AVERY- now that is a coincidence- along with release date of the film: December 25th 1962, in Los Angeles, California. Happy Holidays.