Crack a code

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This page contains details about Fallen London Actions.

From: Work in your Cabinet Noir

Break down the secrets. Force them into the light.

Game Instructions: This will build up your Deciphering... progress quality. (If Midnighter) As a Midnighter, you'll receive more Deciphering... per turn than you otherwise would.

Unlocked with Intercepted Document

Challenge information

Broad, Watchful 175

  • 120 - very chancy (41%)
  • 149 - chancy (51%)
  • 178 - modest (61%)
  • 208 - very modest (71%)
  • 237 - low-risk (81%)
  • 266 - straightforward (91%)
  • 292 - straightforward (100%)

Narrow, A Player of Chess 3

  • 0 - high-risk (30%)
  • 1 - tough (40%)
  • 2 - very chancy (50%)
  • 3 - chancy (60%)
  • 4 - modest (70%)
  • 5 - very modest (80%)
  • 6 - low-risk (90%)
  • 7 and above - straightforward (100%)



[See tables below] ('Sugarplum,' in this case. It is the seed of the cipher.)

Description summary:
The description varies depending on your profession and Intercepted Document. Meanwhile, the seed of the cipher is made of two parts: a prefix that varies with The Airs of London and a suffix that depends on Airs of Balmoral.

[Find the rest of the story at]

Midnighter?First Paragraph
YesFor the work you need certain skills in patience, focus, and negligence of the outside world, for which Saint Joshua is an incomparable teacher. [See deciphering description below]
NoFor the work you need a leaping imagination and a steady hand. [See deciphering description below]
DocumentDeciphering Description
1 - 10, 12You cannot recoil from counting the number of semi-colons on each side of the page and subjecting them to cryptomathematical equations.
11Letter frequencies must be tabulated; minor variations in letter height and ink shade must also be considered. Whoever wrote this document has mastered the Surface arts of deception, if not some of the wilder methods in the Neath.
21The cipher makes use of both substitution and transposition, following the rules of certain Hellish dances. Just here, at the bottom of a paragraph, the letters swap round in a Petal Unfurling, which means you can next expect[…] the Decaying Promenade.
22Most of the writing is invisible as well as enciphered; before you can even begin the decryption, you must view the document in the mirror, with reflected apocyan light, to bring out the ink.
30Each fragment of the letter is its own cipher. Here – the quantities in this cake recipe encode lines in this fragment of a ledger, which contain the names that work as transposition keys for that innocent-seeming postcard from a Surface aunt.
DocumentBeginning of Last Paragraph
1 - 12It also helps to be able to guess the name of the sender's dog.
21It also helps that you were able to recognise a word in one of Hell's languages on the outer envelope.
22Then there is the matter of finding a rare uncensored copy of the Spymaster's Lexicon and finding the page whose colour and finish most closely matches that of the document. Woven linen, pale green. At the bottom of that page is a keyword.
30It also helps that the sender clearly intends for you to decipher this; the message incorporates details that you would know, such the name of your Inconvenient Aunt's least favourite cat.
The Airs of LondonSeed Prefix
1 - 8Sugar
10 - 19Lily
25 - 29Rose
30 - 34Bitter
36 - 39Sour
40 - 44Ivy
48 - 49Snow
50 - 59Honey
60 - 69Lemon
70 - 74Sweet
75 - 77Yule
80 - 89Tea
92 - 94Milk
95 - 98Cream
Airs of BalmoralSeed Suffix
1 - 8[no suffix]
10 - 21plum
25 - 39pot
40 - 47drop
50 - 59cake
61 - 74bud
77 - 86face
90 - 100spoon


Not a code

That symbol is not to be deciphered. That symbol [see table below]
1 - 10invokes a thing that crawls in the dark and seeks the Light-in-Exile.
11is a title, a title that has not yet been given to anyone: how best to translate it? Secretary-Overlord? Pope-Bureaucrat? Triplicate Overseer, Emperor of Reports?
12is cold on the page. Your eye goes fuzzy, as though the lens itself were freezing, just to look at that symbol.
21invokes the rose and the marigold and the lily with the broken stem. It names the weeping of Hell, in Hell's own tongue. Forget it, forget it as fast as you can.
22invokes the death of kings and the slaughter of his people and the burning of their bodies, and the faces of the men who perform such deeds. Forget this, as fast as you can.
30is encodes the name of a Fourth City priest subjected to damnatio memoriae. How the sender got it to stay on the page and not squirm away is a mystery.