Four episodes of the Zodiac Killer documentary on HISTORY have aired now. The fourth one ended with Craig Bauer saying that he has broken Z340. Will episode 5 tell us the solution?

The reactions of my readers on HISTORY’s five part Zodiac Killer TV documentary have been reserved, to say the least. The four episodes that aired so far mainly covered well-known hypotheses about the case, including a number of well-known suspects. The “super computer” Carmel discovered a few facts about the Zodiac cryptograms that had been known before, too.

All episodes are available on a French web portal:


A new crypto mystery?

In spite of all the criticism, there are a number of positive things I see in this documentary. First, the Zodiac Killer case has received a lot of attention. My first blog article about the series proved to be one of the most-read I ever wrote. Second, my friends Craig Bauer …


and David Oranchak …


… appear in this documentary. There’s no doubt that the two have deserved this honor.

And third, the series featured a cryptogram I hadn’t known before: the encrypted text on the Donna Lass search poster. As is explained in the series, Donna Lass was a young woman from the San Francisco area, who disappeared in 1970. Somebody made the following search poster, which contains two encrypted lines:


The cryptogram on this poster looks pretty similar as the Zodiac messages. However, it easy to solve, as it is encrypted in a simple substitution cipher (MASC). The cleartext is: BEWAREIAMSTALKING YOU…DONNA LASS. For more information check Nick Pelling’s blog post about the Donna Lass cryptogram.

It seems quite unlikely that Donna Lass was a victim of the Zodiac Killer. I don’t know why the creators of this poster included a Zodiac-like cryptogram. Probably, they hoped to get more attention.


Is Zodiac 340 solved?

There is one thing about the Zodiac Killer documentary that has thrilled crypto enthusiasts from the beginning: the producers announced that their team has solved one of the Zodiac’s crypto mysteries. The fourth episode presented this announcement as a cliff-hanger: towards the end of the episode crypto expert Craig Bauer calls his fellow investigators and tells them that he has succeeded in breaking Z340, the second Zodiac cryptogram. Details will be revealed in the final part of the series.


If Craig’s announcement was true we will soon witness one of the major codebreaking successes of the century.

Episode number five will air in a few hours. Will it really reveal the solution of one of the world’s most important crypto mysteries? At the NSA Symposium on Cryptologic History a very knowledgable crypto expert (I can’t mention his name, as he wants to stay anonymous) said that he checked Craig’s solution and that in his opinion it was correct.

In a few hours we will know more. I can hardly wait.

Further reading: The Henry Debosnys Murder Case FAQ


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Kommentare (36)

  1. #1 Florian Ress
    12. Dezember 2017

    Wow, you can really hype it up. I was very sceptical about this Series, too much „Show“ in my opinion. But your article, especially the last Part, Makes me really curious…waiting Seems quite painful now.

  2. #2 Rich SantaColoma
    12. Dezember 2017

    Klaus, I am excited to see the last show also. If Craig (and the aforementioned “certifier” of his results…) is correct, this is indeed history in the making. And congratulations, Craig, if you are reading this!

    From the bits of Craig’s solution they showed in episode four, I am thinking that the bottom line of the main text may spell “Richard M Nickson”… a play on the president’s name, of course. From what I could catch, the “signature” of the Zodiac has too few letters to match up to any known suspects, but I could be wrong… Hopefully the answer also solves the mystery of the killer’s identity.

    One of the Reddit forums on the Zodiac Killer has a post by a reader who extrapolated that amount of Craig’s work that they showed, into more plain text characters, and has determined a few more of his possible solution (maybe)… but is more tantalizing than it is satisfying.

    I guess we just have to wait…

  3. #3 Bill Briere
    Wyoming, USA
    12. Dezember 2017

    Up through Episode 4, there is still no new information in this series. The “investigators” Sal LaBarbera and Ken Mains continue to do cheesy reenactments of “discoveries” that have been known about for many years. And Carmel continues to spit out only the observations that Kevin has typed into it — observations and solutions that are not new to anyone who follows this stuff.

  4. #4 Bill Briere
    Wyoming, USA
    12. Dezember 2017

    As others have pointed out, the Donna Lass poster is not even an authentic Zodiac item. The family made it years later, apparently as a desperate stunt to reignite interest in the search for their missing daughter. The poster lists a phone number beginning with 530, which was an area code that didn’t even exist until 1997.

    The simple substitution cipher on the poster does not match the Zodiac’s known cryptograms in system, handwriting, style, or content. Furthermore, the Dynamic Duo ignored the obvious plaintext and went instead with a bizarre interpretation provided by “an anonymous guy in Texas.” [Excerpt: ciphertext “PNWA” yields plaintext “Proceed in a relatively northwest direction until you arrive at an intersection. Make a 90 degree turn.”] That reading spiritually guided them with detailed and lengthy driving instructions to Donner Pass, where they had three detection dogs hit on the sort-of-same general area. They dug a hole in one spot, and found some maggots. As with the bomb they looked for in an earlier episode, they gave up after one attempt, realizing that the Zodiac had outsmarted them yet again and had already been back to remove the evidence.

    So, we are to believe that the real killer buried the body, and then came back later to remove the body — maggots and all. But he was not careful: a few tell-tale grubs remained in the hole for decades, implicating him in his crime.

  5. #5 George Lasry
    12. Dezember 2017

    The team assembled for the task is impressive, without doubt. And like everybody else in the forum, I really want to see this mystery solved at last.
    From the last minutes of episode 4 and the preview to episode 5, watchers were able to transcribe the solution to be shown tonight. The assumption on which the decryption was made is that the cipher is an homophonic cipher.

    I did some analysis on this data and unfortunately the results do not seem convincing. For more details see my comments 11 and 12 in

    From this analysis there is serious doubt that the proposed (partial) decryption is a cryptologically valid one (although the contents would certainly match the mindset and style of the killer).

    As Klaus mentioned, it is good that the subject has be brought to wider public attention and the hope is that this eventually lead to more progress.

  6. #6 Bill Briere
    Wyoming, USA
    12. Dezember 2017

    Then there’s the handwriting analyst, who was manipulated into giving History the answer it needed for the show. In a doctored version of a Zodiac letter, she found the dead-giveaway “grinding” of a punctuation symbol, which had actually been marked up fairly recently by an unwitting Zodiac enthusiast. The original document, which would also have been freely available to History, does not include this feature.

    It makes one wonder what was shown (or not shown) to the “very knowledgeable crypto expert” to get him to say Craig’s solution was legitimate. By the way, I’m not disputing that this anonymous source said that, since it was actually me who asked him the question. I take the man’s endorsement of the “plaintext” with a grain of salt, since he is not a cryptanalyst, and History is known for tricking its contributors.

  7. #7 Bill Briere
    Wyoming, USA
    12. Dezember 2017

    Well, Craig’s solution is soon to be fully revealed. At the end of Episode 4, we can see that he has forced some inconsistent plaintext into the first few lines, which one is hard-pressed to extend beyond that. The wording is reminiscent of so many other anguished contrivances that have preceded this one.

    He lowers expectations and does a preemptive strike against the serious code breakers who will dismiss his results: “I believe I’ve got it. … This is not the cipher of a professional cryptologist.” And then he blows it by adding, “I was immersing myself psychologically today, and I started to see words.”

    I would say that does not sound like the analysis of a professional cryptanalyst. Craig, where are you? Surely you and Dave and the others read these forums. Defend your work. Address our comments.

    Of course, they can’t say much. They took payment and signed nondisclosure agreements.

    As we’ve seen, the signature he works into the end of the cryptogram is “RICHARDMNICKSON.” Finding names in Z-340 has been a long-running game, a sort of parlor trick for armchair cryptanalysts. I seem to recall that Dave has come up with some good ones, too. Many (most?) of the top suspects’ names can be found in there with a little stretch of the imagination.

  8. #8 Rich SantaColoma
    12. Dezember 2017

    Hi Bill, Hi George: I understand your points, both of you… and I am somewhat on the fence. But to address your issues, Bill:

    I of course was also there, when the expert told of checking the solution for Craig. But I do believe he is an expert in cryptology, and I put some weight in that. He was very sure. But balancing that is George’s points… I see what you mean, George, I looked at your comments. Considering all of this together, I am hoping any problems we see will explained, that there is some system derived which will make sense of it.

    And as for the rest of the show, the parts repeating old theories, and leaving out contrary opinion, and the dog searches, and the maggots still being there, and on and on… I agree it is not very… well very impressive, to say the least. It is History’s “showmanship”, and used to sell ads. Unfortunate, I agree.

    But it is no reflection on the guys on the crypto team, I don’t think, nor on Craig’s proposal. I’d watch all the other stuff just to see that… the average viewer would not, and so they need to “color it out”. Oh well.

  9. #9 Rich SantaColoma
    12. Dezember 2017

    Bill… “As we’ve seen, the signature he works into the end of the cryptogram is “RICHARDMNICKSON.” Finding names in Z-340 has been a long-running game…”

    Just one point about that: I think the ‘NICKSON’ is not meant as the killer name, but that the “signature” is in a line further down at the bottom of the page. Whether IT has a name, we cannot yet tell, of course…

  10. #10 Klaus Schmeh
    13. Dezember 2017

    Bart Wenmeckers via Facebook:
    I can’t wait to see the episode.
    There’s be a bit of discussion on the facebook group on the topic but generally raising awareness of the cipher is the main thing. Since the showing i have noticed and increase in member requests to bith the ACA and classical ciphers facebook groups.

  11. #11 Klaus Schmeh
    13. Dezember 2017
  12. #12 George Lasry
    13. Dezember 2017

    @Bart – fully agree
    The contribution of the show to the popularization of the domain of classical ciphers is invaluable. And breakthoughs often come from newcomers to the field…. :-). The topics presented by the team – even if a little dramatized – are still helpful and inspiring to would be solvers are they are not widely known.

    Suspense will soon be over anyway…. Could one of the US members who is able to watch this in real time try to summarize what they saw in this forum?

    The show is not available in most countries and it takes 1-2 days until they are posted. Thanks!

  13. #13 Florian Ress
    13. Dezember 2017

    Can anybody post, what happened in the Season Finale?

  14. #15 Bill Briere
    Wyoming, USA
    13. Dezember 2017

    I rest my case.

  15. #16 Rich SantaColoma
    13. Dezember 2017

    I watched the last episode, and heard the reasoning behind the proposed solution, and saw the proposal. I agree with George and Bill and others that this is not the solution.

    I am not a cipher expert myself, far from it. But:

    1) There are too many variables in the solution, it seems too subjective, both in method of “decipherment” and results given.

    2) It leaves out some cipher characters, and adds plain text characters, without explanation other than making the plaintext a bit closer to meaningful.

    3) Much of the plaintext has little meaning anyway, after this is done.

    4) The given substitutions don’t work with characters in lines after line 8 (as George pointed out in the other blog post comments). But rather than being because the rest is gibberish, I think it may be because the substitutions are incorrect.

    5) The last “O” and “N” in “NICKSON” replace the Zodiac symbol and “Z” in “[symbol] ZODAIK”. But it seems “ZODAIK” is one thing probably intended by the killer.

    In short, I think the “solution” is far too subjective; with too many variables; with little meaning; and so is not correct. I would still be interested to hear the reasons it was thought and said to be correct in the show and elsewhere, though.

  16. #17 Thomas
    13. Dezember 2017

    Who can post the solution and the key? Is it a homophonic cipher? So far as I have understood ep. 5, there has remained gibberish in the middle of the cryptogram that is called a ‘cipher within a cipher’.

  17. #18 Florian Ress
    13. Dezember 2017

    I also think thats not it. I mean the approach seems zodiac-like (using the letters for themselves because that is the last Thing you would expect in a cipher), the black dahlia beginning also fits the picture as well as the Sound of the First 1,5 lines, which really sounds like the tone in the 408. But then the wheels kinda fell off in my opinion..

  18. #19 George Lasry
    13. Dezember 2017

    It is supposedly a homophonic cipher. In such a cipher, each plaintext symbol may be replaced by different cipher symbols (homophones), but to allow for unambiguous decryption, each homophone (cipher symbol) may be mapped to only one plaintext symbol. The solution presented in the show does not follow those rules.

    Here is a transcription of the cipher (found this on Oranchak’s site), and of the decryption from the show:



    The symbol _ means that the plaintext is unknown.

    Here is a mapping of homophones to plaintext symbols, sorted by the number of occurrences.

    [cipher homophone] => [most probable plaintext symbol] (all plaintext symbols appearing in the decryption)

    + => G (GGGFTGGGF)
    p => I (IIOQIY)
    2 => N (TGNNN)
    # => A (AAAA)
    ( => W (TRWW)
    G => O (OBOO)
    O => N (NNNN)
    * => L (LIL)
    F => S (RSS)
    K => R (IRR)
    L => L (LLA)
    R => R (ROR)
    V => S (SSS)
    ^ => I (III)
    d => O (HOO)
    k => K (K.K)
    l => T (TTT)
    z => O (IOO)
    | => I (IVI)
    % => D (DD)
    ) => E (EE)
    5 => E (EN)
    8 => W (WW)
    9 => M (MM)
    > => E (E?)
    B => B (HB)
    D => D (DO)
    H => H (HM)
    J => . (.T)
    M => E (EE)
    N => N (NN)
    P => I (II)
    U => U (UG)
    W => A (AA)
    Y => Y (YY)
    _ => A (AA)
    c => E (HE)
    f => V (VC)
    j => E (EH)
    & => I (I)
    – => I (I)
    . => . (.)
    / => M (M)
    1 => L (L)
    3 => H (H)
    4 => S (S)
    7 => U (U)
    : => T (T)
    ; => A (A)
    I (I)
    @ => G (G)
    C => C (C)
    E => E (E)
    S => S (S)
    T => B (B)
    X => R (R)
    Z => N (N)
    q => Y (Y)
    t => B (B)
    y => Y (Y)

    The ‘probable’ plaintext symbol matching the homophone is the one most frequently
    used. For example, homophone F maps to R (once), and to S twice, so we choose to map it to S. If there is equality, preference is given to the one most similar to the homophone. For example, B maps to both B and H, but we choose B.

    We have 60 homophones, 21 of them are decrypted only once, and 20 are decrypted twice. The remaining 19 homophones appear more than twice.

    We have 8 lines of 17 symbols for which there is a decryption. There are 8 x 17 = 136 symbols in those lines, out of which only 133 are decrypted. This means that we have 133-60 = 73 repetitions. Out of those repetitions, 30 are inconsistent with the ‘probable’ corresponding plaintext symbol mapping, about 41% of the repetitions.

    One of the methods to validate a decryption of a homophonic cipher is to check the consistency of repeated homophones.

    Inconsistent repetitions could arise from several reasons:
    1) Spelling errors in the original plaintext, or encoding errors
    2) Errors in the proposed decryption key

    In Z408, the number of errors of type (1) was small – probably less than 10. Since the fragment of Z340 which has been decrypted has 133(136) symbols, we would have expected at most a couple of type (1) errors. This means that the other errors are almost certainly of type (2).

    Further evidence that the decryption key (and the decryption) is incorrect is the fact that after line 8, it fails to produce anything but gibberish.

    Here is what we get if we do not allow for repetition errors (we use only the ‘probable’ plaintext symbol of each homophone):


    Not only do we get pure gibberish from row 9 and above, but some major parts of the first 8 lines, the decryption look confused.

    Would be happy if someone else could produce a similar analysis, to verify my findings,
    or to contradict them (I would love to be found wrong 🙂

  19. #20 George Lasry
    14. Dezember 2017

    Apologies, the cipher is botched in my above comment, because some of the symbols were special HTML symbols. Here is the correct one:


  20. #21 George Lasry
    14. Dezember 2017

    Sorry, this version is was also wrongly rendered.

    The correct text can be found here

    (can’t get the HTML special characters to work)

  21. #22 Klaus Schmeh
    14. Dezember 2017

    Karin Isberg via Facebook:
    Well, I love the Lego! Of course I’ve been watching all the episodes. Klaus, I love you use of Lego being a fan myself.

  22. #23 Klaus Schmeh
    14. Dezember 2017

    David Allen Wilson via Facebook
    I’m glad there was a little healthy skepticism towards the end of the last episode, especially with the more experienced cryptographer.

  23. #24 Klaus Schmeh
    14. Dezember 2017

    @George Lasry: Thank you for this detailed explanation. I will blog about the solution tomorrow.

  24. #25 SK
    United States
    14. Dezember 2017

    BWAHAHAHAHA! I just watched the episode and I can’t believe you let yourself be conned by the Ghost Hunter Ancient Alien Gold Miner channel. Their solution is something you see in a reddit post by a mentally ill person who is sure they have a “partial solution.”

    I just used ZodiacDecrypto to make my own partial solution just like the History Channel, I think it might be the answer:


    I think I might be on to something!!!!!!!! I got 2 and a half lines, they only got 1, so I’m 2.5x as right, right?

  25. #26 Thomas
    14. Dezember 2017

    @George Lasry
    Isn’t Craig Bauer’s non-gibberish plaintext longer than the first 8 lines you have reproduced in #19 (e.g. the RICHERDMNIKSON…. in the last lines)?

  26. #27 George Lasry
    14. Dezember 2017

    Yes, correct, but this part doesn’t look too good as well.
    This has more inconsistent symbols than consistent ones.

  27. #28 Passing By
    14. Dezember 2017

    Nickson = Son of Nick, “Old Nick” is a Devil’s name.

  28. #29 OK
    14. Dezember 2017

    @George Lasry: thank your for checking the “solution” against dechiff-errors and your documentation. I agree with you, that the “solution” is none. There are more inconsistencies in the show, I suppose. So it’s no more and no less than entertainment.

  29. #30 OK
    14. Dezember 2017

    I don’t think that the Donna Lass – Solution is right

    B E W A R E I A M S T A L K I N G Y O U . . . . D O N N A L A S S
    E P T W Y P N W A _ V W K S N Z F ^ ^ Q . . . . / ^ Z Z W K W _ _ .

    Look at you two triangles (^ in transcription) before the Q and 4 dots.

    How can this be YO (of YOu) ???

    If DONNA is correct, the triangle is an O.. So the word would be OO? and not YOU. This is definitely more than a typo.

  30. #31 Breaker
    19. Dezember 2017

    Everyone here should take a look at the Curse of Oak Island show that Kevin Knight was on… it he proposed to be searching for a solve to a hand drawn “Templar/Masonic-esque” Cipher that clearly shows the name La Vasseur or La Buse….the Pirate….written at the bottom and then added was the McGinnis name next to it…..

    In it he proposes that the answers to this hand drawn map were made to be used to solve a mystery of a “Treasure Map”…….

    The Answers Kevin Knight Proposes?

    1)”Taking Nine Enemas” (Horizontal Transposition)
    2)”Clouds Dude” (Horizontal Transposition)
    3)”Bro Jews Liked Oven” (Vertical Read from Transposition)

    Now to allow this on Mainstream TV with 35 Million People Watching…..there would be no other interests in seeing his “Computer” at work in ANY other TV shows….

    But somehow he makes it to the show…….cause he’s spooky and looks like one of the Suspects from the past….


    And David Oranchek has the pull to convince the NSA to allow him to present his solves to them….in a speech that shows us …..”When Do We Know When To Stop Trying To Solve The Z340?”

    LOL…..The Answer is clear ……

    When its actually solved I would say……

  31. #32 Breaker
    Outer Space - Orion Star Constellation
    19. Dezember 2017

    The Z340 can be seen in a few different ways….

    First the Star Quadrants are identified…..HERcules in the NW and BOOTES in the SE quads are made from the dots…..

    The next thing to do is to take the symbols and separate them from the letters……

    These are the two grids provided of Ciphertext and if made appropriately they arrange in columns that leave one letter out at the end of each

    From here the system is clearly another Homophonic Cipher that is said to be the same in the Z13 Letter……


    And from here you see its another Homophonic…..

    But he does not stop here……this is the center of the conspiracy behind the confusion…..stupidity and assertions have directed the assumptions without solid results….

    Now here is the method of the creation of the system to create the repetitions in the Homophonic……

    There is a Vigenere Tableau that features a shift…..

    This is created by entering the keyword in the vertical position of the first column……this shift is seen to allow for numerous repetitions and even produce strange patterns of double bigrams and patterns that DAVE CANT SEEM TO RECOGNIZE…

    These are formed from the geometric matrices that are formed in the 26 x 26 letter Vigenere……

    The shift or the “Key Phrase” is even hinted at in the cipher itself……at the top…..

    He says the phrase ……..BY THE WAY HAVE YOU——-MY NAME IS…….as a hint.

    This should be BY THE WAY YOU HAVE…..

    This is the creation of a switcheroo….taking the constellation HERCULES……we get HER CLUES ——GOD….as seen in the first line….

    This is the hint at the shift……

    The phrase is HER CLUE WRATH OF GOD

    And that is the end of the hints……from here you have to know the phrase used in that operation……WRATH OF GOD….by Golda Meir.


    Add that Vertically into the first column of the Vigenere Cipher….and create the necessary shift to create the results from the Ciphertext that was separated from the Symbols in the first step…….

    Run it through the cipher and see that the first hints of HER BOOTES are seen to take effect as a full script of a Behind the Green Door – Type of statements….

    The first resulting lines from the Vigenere is :


    He was not playing around…….

    I know EXACTLY who wrote this…….

    Dave and Kevin cant possibly air this……nor could they ever figure it out without the shift Key Phrase……

    All Homophonic Ciphers require a Key Phrase to unlock them….

    The Hardens Tried a Trial & Error method…..which showed the variables repeating ……but did not show the patterns from a phrase that shifted the Z408 Vigenere to produce that cipher’s plaintext.

  32. #33 Breaker
    19. Dezember 2017

    BTW they never proposed to follow the solves through the entirety….

    The first one was barely finished as the last 18 letters were a clue to the Shift that is used to create the Homophonic….

    The phrase here is hinted at being……”BEFORE I ATEMPT THE PIT TEMPEST

    These shifts if entered properly will produce the Harden Solves as well as showing a hint of the next clues to look for in the star quadrants…..these were required to find the star maps….

    As the Tempest held these exact same specific solves of Bootes and Hercules…..

  33. #34 Breaker
    19. Dezember 2017

    The best example and visual composition can be found here…..

    I have over a dozen of the Zodiac and Scorpion Solves….

    Some of the templates are still being used in more recent times by Intelligence Communities in attacks and hidden communiques of Intel which is discussed in these videos…..

    THE ORANGE THEORY – The Adventures of MR. Z

  34. #35 Joseph Donahue
    14. August 2021

    Everything is fine, but I had an account in DrawCrowd and although my art is not surprising because I do not dedicate the time I need, I uploaded several of my sketches and ideas, and the League of Legends people stole these concepts to create Zoe and El new NUNU and now … how do I do it?

  35. #36 Ashley Jones
    3. September 2021

    I believe that cicada 3011 was used to recruit people to intelligence agencies such as the NSA. One thing that seems very suspicious are the questions. Those questions are not there to see if you believe in privacy and meet some moral/ethics, but to see if you’re going to be okay with going against it.