Killer In The Code – Chapter 4: Code Makers and Breakers

Podcast: Killer In The Code

Host: Michael Connelly

Date: January 8, 2026

Episode Theme:

This riveting installment dives into the groundbreaking work of professional cryptographers brought in to verify Alex Baber’s claimed solution to the Zodiac’s infamous Z13 cipher—and how, in doing so, they made major breakthroughs of their own. It’s an in-depth exploration of how cryptology, forensic investigation, and cold case sleuthing may have cracked open the Black Dahlia, Zodiac, and Sherry Jo Bates murders, linking them in chilling, unprecedented ways.

Key Discussion Points and Major Insights

1. Confirming Alex Baber's Solution to the Z13 ("My Name Is") Zodiac Cipher

[00:02 - 03:18]

• Michael Connelly recounts how cold case consultant Alex Baber used AI and painstaking legwork to break the legendary Z13 cipher, narrowing 71 million names to one: Marvin Merrill (aka Marvin Margolis)—already a top Black Dahlia suspect.
• Connelly recruited legendary cyber sleuths—Ed Giorgio (NSA’s only dual chief code breaker/maker), Patrick Henry, and Rich Wisniewski—to independently vet Baber’s breakthrough.

Notable Quote:

"[Giorgio] called Baber's work the greatest sleuth story ever told. And as he continues work on the case, he is not backing down."
— Michael Connelly [03:00]

2. Laying Out Zodiac’s Cipher History and Methods

[03:18 - 09:45]

• The Z408: First Zodiac cipher, a grid-based simple substitution code, solved within a week by schoolteachers. Last line ("Z18") unbroken—until now (see later segments).
• The Z340: Considerably more complex; utilized "Knight’s Tour" permutation based on chess moves. Broke only after 50 years due to increased sophistication.
• The Z13 ("My Name Is..."): The cipher at the heart of Baber’s investigation. Zodiac challenged codebreakers to find his name in 13 characters, applying both substitution and permutation.

Explained by Experts:

• Substitution: Replacing letters with symbols/numbers.
• Permutation: Rearranging ciphered text according to a systematic method—commonly via "columnar transposition" using a keyword.

3. Breaking Down Baber’s Solution—And the Cryptographers’ Peer Review

[09:45 - 15:46]

• Patrick Henry reviews cryptography manuals from the 1940s-60s to reconstruct how the Zodiac might have learned code-making, citing Helen Gaines’ seminal text Cryptanalysis: A Study of Ciphers and Their Solution.
• Baber’s innovation: Recognizes Z13 could be laid out in a grid (two rows, seven columns—adding a null for uniformity), which opened the door to pinpointing its construction.
• The cryptography team confirms Baber's decrypted name—Marvin Merrill—matches the solution, noting the method is "very consistent with [the Zodiac’s] prior methods of encryption."

"The permutation that Alex gave us, we believe is correct in part because the method of encryption is very consistent with his prior methods."
— Ed Giorgio [11:19]

4. The "Elizabeth" Keyword—A Chilling Connection to Black Dahlia

[14:42 - 16:39]

• Patrick Henry, undeterred, seeks out a permutation keyword (the word that determines how columns were rearranged in the cipher grid).
• The eureka moment: The permutation key is "Elizabeth" (as in Elizabeth Short, the Black Dahlia), with the pattern matching standard cryptography manuals. The cipher creator omits the first "d"—a common cipher convention.

"Patrick found that the keyword that unlocked the door on Z13 was Elizabeth...the Zodiac had dropped the first D in Elizabeth."
— Michael Connelly [15:10]

"It was generated by a standard scheme using the keyword Elizabeth."
— Patrick Henry [15:34]

5. Linking Three Murder Cases through Cipher Construction

[16:39 - 21:25]

• The method, keyword, and solution form a uniquely structured and plausible process, unlike thousands of alternative "solutions" to cipher puzzles.

"From the Z13 to Marvin Merrill, we have a believable, plausible method ... and [it] all hangs together."
— Patrick Henry [18:21]

• The team ponders Zodiac’s psychological motive for leaving a keyword connecting him to Black Dahlia:

"He was trying to leave clues...tantalizing but hard. So when somebody did finally come up with the solution, they would be able to see how it was constructed."
— Patrick Henry [19:51]

6. The Sherry Jo Bates Connection—Another Cipher, Another Victim

[21:25 - 27:31]

• With a keyword used in the permutation, the codebreakers next investigate the substitution scheme’s keyword.
• The AI-derived solution: Of 19 possible candidates, "Sherry Jo" (with a rare spelling) emerges. Sherry Jo Bates—a Riverside college student murdered in 1966—has long been a Zodiac "possible," but never officially linked.
• The cryptographers realize: The Zodiac used the Bates’s name as a keyword, months before any public suggestion of a connection.

"So this was kind of the second aha moment."
— Ed Giorgio [22:45]

• Veteran homicide detective Rick Jackson is stunned:

“That would rivet any detective...it’s off the charts. That kind of stuff just doesn’t happen.”
— Rick Jackson & Ed Giorgio [26:34–27:02]

• Missy Roberts, ex-LAPD Cold Case Unit, underscores that MOs evolve; weapon changes and different victimology are not disqualifying:

“We see the killer evolving and getting better at his craft. And there’s a reason why he wasn’t caught, because he did evolve.”
— Missy Roberts [27:43]

7. New Evidence: Marvin Merrill’s Proximity and Knowledge

[29:29–30:44]

• At the time of the Bates murder, Merrill lived only an hour away and was running an auto repair shop, giving him knowledge to tamper with cars—exactly as in the Sherry Jo case.
• Baber’s team continues to study Merrill’s possible involvement.

“This alone validates my initial discovery...another layer of credibility because it was independently discovered.” — Patrick Henry (on the confirmation of Baber’s work) [30:25]

8. The Z408’s Final Secret (Z18) Revealed—A New Breakthrough

[30:44 - 33:10]

• Swedish data analyst Thomas Heffner, having seen reports on Baber’s Z13 breakthrough, applies the same methodology to the enigmatic, previously undecoded last line ("Z18") of the Zodiac’s Z408.
• His result: yet again, the name "Marvin Merrill" is revealed.

“Work itself was about seeing the patterns and trying to understand the system itself behind it. And it sort of puts you in this space where you are trying to think like the person who created these patterns in the system...it’s an eerie feeling.”
— Thomas Heffner [31:14]

• Baber and cryptography team (initially) confirm the solution as "rock solid" and plausible.

"It's solid. It's rock solid. I tested it first twice to make sure it was accurate."
— Patrick Henry [33:03]

9. The Z32 Cipher: No Closed Solution, But Strong Physical Evidence

[33:10 - 35:36]

• Patrick Henry evaluates Baber’s work on the Z32 cipher but stresses that, due to the cipher’s simple structure, nearly any solution is possible. However, physical evidence—map alignment pointing to the Black Dahlia burial site (Mount Diablo)—is persuasive.

“We don't have any sort of convincing argument that this solution is structurally any better than any other solution. The evidence...outside of the cipher has some weight to it.”
— Patrick Henry [34:45]

• Keywords, which were crucial for Z13’s confidence, are absent in Z32, making cryptanalysis less definitive.

10. Reflections on the Investigation and Its Impact

[35:36 - 36:51]

• Ed Giorgio reflects on why the cryptographers—pulling from knowledge that once would be classified—were drawn to this puzzle and its potential to rewrite history.

“This is my passion. It's enormously fun...I have a strong connection to the history of code breaking. We're in it to solve important problems. We think this is important, but we also think it's terribly exciting.”
— Ed Giorgio [35:48]

Notable Quotes & Memorable Moments

• “This all began with cold case consultant Alex Baber cracking the Holy Grail of zodiac ciphers. The z13...believed to be unbreakable.”
  — Michael Connelly [00:34]

• “The world of cryptology is a mystery in itself...what they say is as hard to decipher as the codes they make or break.”
  — Michael Connelly [03:22]

• “You can make this cipher decrypt to any name you like. That’s not quite true, but it's not strictly incorrect.”
  — Ed Giorgio [04:02]

• “You turn a key to unlock a door. Patrick found that the keyword that unlocked the door on Z13 was Elizabeth.”
  — Michael Connelly [15:10]

• “That's something that really lends weight to this solution being correct. It's not just an anagram...It's a very structured reordering...”
  — Patrick Henry [15:46]

• “This alone validates my initial discovery...another layer of credibility because it was independently discovered.”
  — Patrick Henry [30:25]

• “I have a strong connection to the history of code breaking. We're in it to solve important problems. We think this is important, but we also think it's terribly exciting.”
  — Ed Giorgio [35:48]

Timestamps for Critical Segments

• 00:02 — Episode open; Michael Connelly explains the challenge and importance of decoding Z13
• 03:18 — Ed Giorgio and codebreaker team confirm Baber’s break
• 06:06 — Knight’s Tour, Z340, and increased Zodiac cipher complexity
• 09:06 — Patrick Henry discusses cryptography literature; possible influences on Zodiac
• 15:10 — Discovery of “Elizabeth” as the permutation keyword
• 22:45 — The “second aha moment”: Sherry Jo as a substitution key
• 27:43 — Missy Roberts on killer’s evolving MO
• 30:44 — Heffner cracks Z18; Marvin Merrill’s name emerges again
• 33:39 — Z32 cipher's plausibility, limitations
• 35:48 — Giorgio’s closing reflections on their work

Summary

Chapter 4 of Killer In The Code unravels how Alex Baber’s AI-aided, dogged investigation into the Zodiac ciphers not only cracked a legendary code, but—now independently verified by top cryptologists—draws a dark line connecting the Zodiac, Black Dahlia, and Sherry Jo Bates murders to one man: Marvin Merrill. The episode details the highly methodical, evidence-driven steps taken to decode the Zodiac’s Z13 and Z18 ciphers, underscores the importance of the "Elizabeth" and "Sherry Jo" keywords, and features expert voices reflecting both on cryptographic innovation and the evolving psychology of serial killers. If the evidence stands, it not only answers the Zodiac’s ultimate taunt—"My name is..."—but reveals a killer’s chilling intent to be found.

For diagrams, further breakdowns, and cryptography resource links, visit killerinthecode.com.