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A WWII spy who hid codes in her knitting (amightygirl.com)
308 points by marymkearney on April 18, 2023 | hide | past | favorite | 78 comments

The details of the technique in the article seem to be lacking. There's a bit more on the Wikipedia:

> When she obtained any military intelligence, she encoded it for transmitting by knitting using one-time codes hidden on a piece of silk that she used to tie up her hair; she would translate them using Morse code equipment.


oddly I was reading this story yesterday because someone linked to an item of clothes from a shop which also contained a silk code scarf: https://adversarialfashion.com/products/wwii-code-cipher-sca...

it's unclear from the images in the shop but the code isn't the circuit diagram-ish things but a table in the middle, which reproduces this, an actual SOE silk code: http://www.jproc.ca/crypto/silkcode_chart_b.jpg

This is apparently a 'Worked Out Key' cipher, not a OTP as mentioned in the article, but both were in use due to Leo Marks https://en.wikipedia.org/wiki/Leo_Marks#:~:text=Developments....

(in fact, here's a photo of Leo with one of these code tables https://www.historynet.com/was-this-the-uks-worst-spy-failur... )

Comprehensive answer with everything backed up by links, well done mate!

"Between Silk and Cyanide" was a great book with some very interesting and funny stories from SOE. I recommend it.

I'd love to see photos of the original pattern. But I just bought that scarf because it's pretty anyway.

opsec slip-up my dear, now the gpt4 driven facial recognition cameras are looking for your scarf! but, you will look great so you have that going for you, important for getting your mugshot to go viral, like Jeanne d'Arc

I liked this: "The patterns on the goods in this shop are designed to trigger Automated License Plate Readers, injecting junk data in to the systems used by the State and its contractors to monitor and track civilians and their locations."

Wikipedia also tells us that aged 102, "she is the last living female SOE agent of the forty who worked in France during World War II." Quite the life.

Christopher Lee (of Dracula, James Bond, Star Wars and LOTR fame) worked for the SOE, did he not? I wonder if they ever met.

He was attached but not part of the SOE. Much of his claimed spec ops/spy work stemmed from exaggerations others made that he made no real effort to correct. https://www.spectator.co.uk/article/who-dares-lies/

Not that it makes his service any less incredible or admirable in my book.

He also joined the volunteer forces fighting for Finland against the Soviet invasion in the winter war of 1939.


Quite amazing when you contrast it with going to Ukraine as a volunteer today.

With the UK's kinda-draconian Official Secrets Act, and tendency to keep WWII stuff Secret for extremely long periods - was telling the truth a good option for him?

I think that's misworded.

The actual quote from Phyllis was " I always carried knitting because my codes were on a piece of silk".

There's no need for knitting to be involved in the encoding. She had a message (unclear if it was a message she received or her own personal knowledge; likely her own knowledge from observing Nazi/German soldiers), and she had a silk with the code keys, and she had a transmission station.

Just let me believe she was knitting key patterns doing the encryption in her head

The whole story is fake

The wikipedia article mentioned by another commenter is a bit drier but more informative. The knitting kit stuff is just flourishing and actually was not that important. What should have been emphasized is the sheer courage of a teenager being dropped behind the enemy lines as a spy. Spies, moreso in a war, are almost always executed, usually after a gruesome session of torture to extract information.

>a teenager

Not to detract from her courage, just to clarify: She was 23, posing as a teenager behind enemy lines. TFA says she was 20 when she joined the WAAF in '41 and started that mission May '44.

Unrelated, but it mentions she was part of the "Scientist" circuit, which was run by André Grandclément [0] who turned out to be a double agent. Most of Latour's circuit were wiped out.

[0] https://en.wikipedia.org/wiki/Andr%C3%A9_Grandcl%C3%A9ment

What she endured is hard for me to comprehend. Humans like Phyllis are treasures of the human capacity.

I've been thinking about this a lot lately. Life is hard, even without war, war being something I've been fortunate to have not experienced. I know the capacity is there as Phyllis proves, and I'm no absolutist when it comes to strife, but, just wow.

Not hidden in the knitting in the sense of the specific stitches (which is also very cool: https://www.popsci.com/story/diy/secret-code-messages-knitti...) but it seems she needed the knitting needle to insert the one-time codes (on a piece of silk) into a shoelace. Amazing story.

That was my first thought too. Different stitches such as knits and purls could serve very well as dots and dashes. Maybe that could've been too easily spotted.

She transmitted her messages via radio, which allowed her to skip the messy business of smuggling knitted intelligence out of occupied France.

That being said, I'm 100% stealing the knitting-as-writing concept for a TTRPG campaign. It's just too cool of an idea to go to waste.

Thank you! I remember learning about this in an art history class decades ago, but I'd completely forgotten and I never would've remembered the name.

I recently read Between Silk and Cyanide, the autobiography of the guy who made the codes for the OP's SOE.


He's the guy who came up with the idea of using silk for codes, as silk won't be felt during pat-downs (paper will be felt). There's lots in the book of trying to work with local business who were obviously not willing to part with their valuable silk.

The book goes much more into details of transmitting these codes, the hassle of bruteforcing when somebody misremembered their code or mistranposed (there was an army of women working 24/7 trying out all possible codes). Highly suggested if the OP piqued your interest!

Here to second that recommendation.

Steve Bellovin wrote a review of "Between Silk and Cyanide" back on the old cryptography@c2.net mailing list that prompted me to buy the book: https://www.mail-archive.com/cryptography@c2.net/msg04572.ht... (The whole thread is good, BTW.)

The seriousness of the topic really left a mark with me (thinking about agents being tortured and killed as a result of poor opsec or cryptographic vulnerabilities). I'm glad that the work I do doesn't have those consequences.

Although I have no specific complaint about this book, I actually didn't enjoy reading it as much as I had hoped, when it first came out. Leo Marks somehow just didn't make me want to read more, where Solly Zuckerman's book "from apes to warlords" which is about Operations Research and the bombing campaign in part totally did. Also R.V. Jones "most secret war" is a damn fine read.

If I remember it right, Leo Marks is the one who proved to the French their codes were completely bogus by breaking them, in front of their eyes with pen and paper. I bet they hated it, but it may have been highly beneficial it was irrefutable.

Meanwhile the UK is now arresting French people who refuse to share information about striking protesters in France.


This has no replies. I only refresh hn maybe once every day or two, to go through what's on the front page and the comments. This is awful.

Last week's episode of "Patented" discussed the use of sink for escape maps given to British soldiers in WWII. Check out the detail of those maps!


And of course this HN post needs a reference to Neal Stephenson's "The Confusion" (The Baroque Cycle, Vol. 2) where Eliza codes her letters into her knitting.

My grandmother was in the resistance. Being around 14 years old, she was used as a courier and would hide messages in a pile of beans in the cellar. One day the enemy came and they must have been tipped off because they were searching everything. A young officer was searching the cellar and rummaged through the beans with his hand. At one point he stopped, his hand still among the beans, took a long look at my grandmother and shouted "Nothing here!". They left and she never met the officer again to thank him.

Another spy, Lord Baden Powell, hid maps of enemy installations in a drawing book while pretending to be a naturalist (which he was).


This article makes it sound like Doyle's knitting provided the codes to encrypt her messages that she was sending--not that she was encoding her actual messages in knitting.

In The Tale of Two Cities, Dickens has a character named Madame Defarge who knits the list of names that the revolutionaries want to execute.

> This article makes it sound like Doyle's knitting provided the codes to encrypt her messages that she was sending

To be fair, the title makes it sound like this. The article does mentions the silk code and how it was hidden.

My dad is a ham and also a weaver. He puts "May you be happy" in Morse Code in the dish towels he makes.

Through all of this, I'm still confused on how the knitting was pertinent. Was she actually knitting with a morse code style pattern? It sounds more like she just used the knitting as a cover. If there was actual knitting, what was she knitting? Scarves, hats, blankets? How did the knitted item get into hands of those that needed it? Either my reading comprehension has gotten so bad that this makes no sense, or some details are sadly left out of the story and from links within the comments here.

It wasn't "hidden in knitting", and it's not just you, the title is terrible.

She used a knitting needle to insert a silk cypher sheet into a shoelace, which she used to tie her hair. Since the knitting needle was necessary to stash the rolled up sheet of silk in the shoelace, she'd carry her knitting as cover.

I was noticing if you use the same seed with some of the image generating transformers, that one image of some waves and the next of some clouds or something, will have the peeks and troughs of the waves and the cloud pattern in equivalent places. It made me think is there a way of hiding data in generated images by using specific seeds that leave symbols that can be recovered with the right transformation.

Classic steganography may be of interest to you.

Also Johnny Mnemonic

In a similar vein, nobody would notice the old woman sitting at the railway station, knitting away, waiting for a train. In fact, what she was doing was including coded details into her knitting of train & troop movements, to be passed onto the Resistance at the end of the day.

Lots of brave people contributed to the war effort in surreptitious ways.

She was not old at that time, but a teenager, and her cover to observe german positions was, according to article being an itinerant seller of SOAP in a bicycle.

Being a young woman, according to the wikipedia, she was also able to entertain conversations with the young german soldiers to gather more information.

It looks like the knitting kit was just a clever way of having a place to hide the OTP codes she used and keeping track of the ones already used. Also, according to the wikipedia she was once detained by the germans for interrogation, but they didn't think of checking her hair tie.

Pretty clever IMHO, not to mention the mind-boggling level of courage.

I wasn't talking about this woman, but other local women who also did their bit for the Resistance while being completely "invisible".

Is this a true story? If so, do you have more details or source to read about?

This article mentions the practice in WW1 and refers to it being done in WW2:


It also mentions the subject of OP's article too. I have seen an old piece of knitting from WW2 used to convey messages in a military museum in Portsmouth, UK.

And this link includes details on how to do it:


I read somewhere some Qwghlmian duchess was doing that centuries ago.

Presumably, that last name is ciphertext, and the family keys were lost to history.

Neal Stephenson isn't under obligations to reveal which specific sources prompted his creative writing. I've read comments that other authors dread subject matter experts un-announced suggesting things: it kills the idea for them, in a way ASKING for information doesn't.

Something I've been thinking about lately is how World War Two is receding from our collective memory and how "archaic" it will eventually come to be seen? The last veterans will pass away within the next few years. In less than twenty years, WWII will have happened a century ago. It will be as ancient as the Franco-Prussan War of 1871 to someone who was alive in 1971, or to World War One to people today. Humanity will move into the 22nd century and WWII will be two centuries old. Two centuries ago, you had the Napoleonic Wars. In the 23rd century, it will be 300 years old. 300 years ago, you had the War of the Spanish Succession (a war only nerds know about at this point) and the Seven Years War.

Will Hitler continue to be the go-to example of prime evil in people's minds then? I'm not so certain.

Pupils in the 22nd century will read about the Enigma machine and the codebreakers of Bletchley Park, think to themselves "how primitive they were then", then send their friend a text using an unbreakable post-quantum encryption algorithm.

West Point cadets will read about how German and Soviet commanders got creative with Panzers and T-34s, then go into a virtual simulation where they press a few buttons to coordinate a multi-domain kill chain to direct a smart cruise missile from a destroyer in the South Atlantic to a tank force in Pakistan, thousands of miles away.

Aerospace engineering students will read about the V2 rockets, then start their summer internships on Lunar Base 3 (on the actual Moon).

And eventually, will they even stop learning about it?

Are there any lessons to draw here about our view of the past and the lessons we can learn from them? Our ancestors were just as creative and smart as we, they just had more limited means.

In another context, I gave a back of the envelope calculation that WWII comprised approximately 1% of human history -- roughly 20 billion person-years were lived during that time, and heavily influenced by it, compared to around 2.3 trillion person-years lived since anatomically modern humans first arose a couple-three hundred thousand years ago.

Vietnam lasted longer, but only was a salient issue for a much smaller fraction of the world's population at the time, so probably less than a tenth of the person-years lived in the shadow of WWII were similarly affected by the Vietnam War.

Unless there is a WWIII, the second World War will probably be the war of the human species, and a significant part of our history for centuries to come.

Just to further back up your point when you look at the cost of US wars here: http://imgs.xkcd.com/comics/money_huge.png

WW2 is head and shoulders above everything else.

The interesting thing to me is how much less subsequent wars have made it into popular culture. Vietnam is still pivotal in the US, but the Iraq war and twenty-year occupation of Afghanistan have kind of vanished? There's a sort of layer of "generic middle Eastern war" in popular culture, via Call Of Duty and action movies, but not anything more realistic?

> Will Hitler continue to be the go-to example of prime evil in people's minds then? I'm not so certain.

Prior to this it seems to have been https://en.wikipedia.org/wiki/Sack_of_Magdeburg (someone once asked the question on Reddit "what the go-to example of war horror was before WW2")

Once the TV cameras re-enter eastern Ukraine perhaps we will see. Or perhaps not, given that it will be too horrific to show on social media or TV anywhere.

> Something I've been thinking about lately is how World War Two is receding from our collective memory and how "archaic" it will eventually come to be seen?

Yeah, we're already seeing this with Holocaust denialism - as ever more and more witnesses die, revisionists have an ever easier game denying or downplaying what happened, and with no small "thanks" to the US who never bothered to follow the European example and criminalize Holocaust denial.

At least for the Holocaust, we have the physical evidence kept alive in the former death camp sites... but what about those atrocities that didn't leave much physical evidence?

Criminalizing lies is dangerous, because the government can decide what it thinks are lies. If government wants to fight lies, money is better spent funding the spread of good information.

The US used to get this right by outlawing media consolidation and foreign ownership, then simply not having a domestic government-run propaganda outlet.

Of course, those rules were all repealed, and now we have things like Fox News which simultaneously violates all three of those rules (it isn’t government funded, but it is a de facto mouthpiece for the federal GOP). The left wing media has been playing catch up ever since.

At least there is one conservative conservative TV source left. I would feel very uncomfortable in a one-sided situation with no liberal or conservative news sources.

It's bad enough that only a few companies own basically every source already. One evening party's worth of people control what is basically the 'truth' in our nation.

One? Lol. OANN and Newsmax still exist.

I've never seen OANN or Newsmax. Must be some obscure channels.

Fox News is the only TV source I've heard of mainstream conservatives watching.

I think World wars won't be easily forgotten because they have amazing branding through the use of the word "world" that is timeless. Unless we seriously screw up something about naming World War III I think we can keep the franchise fresh for ages.

> Will Hitler continue to be the go-to example of prime evil in people's minds then?

I think so, as long as people believe in holocaust and no one else tops him.

> And eventually, will they even stop learning about it?

We do still learn about pharaohs ... and cowboys for some reason. Some history just gets immortalized in tropes.

I suspect that in the year 4000, Madonna will still be a known quantity. Michael Jackson, not so much.

>then send their friend a text using an unbreakable post- quantum encryption algorithm.

You're wrong there. They won't because governments will move to ban them so that they can carry on snooping. It's more likely that the texts will be simutaneously uploaded onto a publicly accessible database, which will be encouraged because "only criminals have something they want to hide".

The spy who didn’t need to come in from the cold.

Every now and then, QI-stories I learned 10+ years ago pops up. I don't think this fact (...) is that old, but I love it.

> For seventy years, Doyle's contributions to the war effort were largely unheralded, but she was finally given her due in 2014 when she was awarded France's highest honor, the Chevalier of the Legion of Honour.

Funny enough it's been publicly known for about that long.

I guess that's what makes it really Quite Interesting. :)

Steganography is hiding information in plain sight. This is knitting steganography.

reminds me of 'Courage Mom' from movie Wag the dog.

Wasn’t this also a plot point in The Cryptonomicon?

It was in The Baroque Cycle

Ah, it’s been almost a couple decades since I read the books, I imagine that time has smeared a lot of plot points from one book to the other and back again.

It was kinda cool that he recycled some family names between the stories but fifteen years on I can't keep the two straight now.

It was more than just recycling—those were meant to be ancestors of Cryptonomicon characters (except, obviously, for Enoch Root).

Apparently she is still alive at 102!

Neal Stephenson did it first!

Better article, scroll down to the "From the Archives - Interview with Pippa from 2009" -


"Germany was far more advanced with their DF (direction finding or radio detecting apparatus) than the Allies. They were about an hour and a half behind me each time I transmitted. Each message might take me about half an hour so I didn't have much time. It was an awful problem for me so I had to ask for one of the three DF near me to be taken out. They threw a grenade at it.

A German woman and two small children died. I knew I was responsible for their deaths. It was a horrible feeling."

Leo Marks - "Between Silk and Cyanide: A Codemaker's War, 1941-1945" -

"Clearly disappointed that he couldn't see a problem, he said that silk codes could easily be camouflaged in toothpaste tubes with special compartments, in shoelaces with soft tubes inside, and in an infinite number of conventional objects which would certainly stand up to random street searches, and might even be safe under close examination"

The article does contain good details:

  With just one blue cotton dress to her name she pedalled around the countryside selling soap to mostly German soldiers, crossing fields on foot to where she had hidden another bicycle. The Gestapo and SS were everywhere. And to add to the confusion and danger a double agent was working in the area. The SOE operative was friendly and talkative whenever she met German soldiers – "I'd talk so much about anything and everything, trying to be 'helpful' and they'd get sick of me" - and was constantly moving through the countryside where she was transmitting the information so urgently needed by the Allied Command.

  "I always carried knitting because my codes were on a piece of silk – I had about 2000 I could use. When I used a code I would just pinprick it to indicate it had gone. I wrapped the piece of silk around a knitting needle and put it in a flat shoe lace which I used to tie my hair up."

  Once she was loaded into a truck along with other locals and taken to the police station for questioning. "I can remember being taken to the station and a female soldier made us take our clothes off to see if we were hiding anything. She was looking suspiciously at my hair so I just pulled my lace off and shook my head. That seemed to satisfy her. I tied my hair back up with the lace- it was a nerve-wracking moment."

Apparently this was an urban legend. Good movie idea but not accurate

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