Cryptonomicon

The card on top is an eight of spades. Skimming it and a few more cards out of the way, he finds a joker, with small stars in the corners; according to hints that Enoch has already dropped, this is the A joker. It's the work of a moment to slip it beneath the card below, which happens to be a Jack of clubs. About two-thirds of the way down into the pack he finds a big-star joker, and B stands for Big, so he knows that is Joker B; he moves it down two cards, below the six of clubs and the nine of diamonds. Straightening up the pack and then smearing though it once more, he sticks various fingers in as he re-finds those jacks, and ends up with a good half of the pack--the full inter-Joker span, plus the two Jokers themselves--trapped between his index and forefingers. The thinner stacks above and below he pulls out and swaps with each other. Enoch watches all of this and seems to approve.

Randy pushes out the bottom-most card, now, and it turns out to be a jack of clubs. On second thought he pulls that jack out and leaves it on his knee for the time being, so he won't mess the next part up. According to the mnemonic symbols he's marked on his fingernails, the numerical value of this jack of clubs is simply 11. So, starting from the top of the deck, he counts down to the eleventh card, cuts the deck below it, then swaps the two halves, and finally takes the jack of clubs off his knee and puts it on the bottom of the deck again.

The card on the top of the deck is now a joker. "What's the numerical value for a joker?" he asks, and Enoch Root says, "it's fifty-three, for either one of them." So Randy gets a free ride this time; he knows that if he begins counting down from the top of the deck, when he reaches 53 he'll be staring at the last card. And that card happens to be the Jack of Clubs, with a value of 11. Eleven, then is the first number in the keystream.

Now, the first letter in the ciphertext that Enoch Root wrote on the napkin is O, and (setting the deck of cards down, now, so that he can count through the alphabet on his fingers) O is letter fifteen. If he subtracts eleven from that, he gets four, and he doesn't even have to count on his fingers to know that letter number four is D. He has one letter deciphered.

Randy remarks, "We still haven't gotten to your being arrested."

"Yes! Well, it's like this," says Enoch Root. "Mr. Wing has been digging some holes of his own up in the jungle lately. A lot of trucks have been going through. Ruining the roads. Running over stray dogs, which as you know are an important food source for these people. A boy was hit by one of these trucks and has been in our hospital ever since. The runoff from Mr. Wing's operations has been fouling the river that many people rely on for fresh water. And there are questions of ownership too--some feel that Mr. Wing is encroaching on land that is properly owned by the government. Which in some extremely attenuated sense, means it is owned by the people."

"Does he have a permit?"

"Ah! Once again your knowledge of local politics is evident. As you know, the normal procedure is for local officials to approach people who are digging large holes in the ground, or undertaking any kind of productive or destructive activity whatsoever, and demand that they obtain a permit, which simply means that they want a bribe or else they'll raise a stink about it. Mr. Wing's company has not obtained a permit."

"Has a stink been raised?"

"Yes. But Mr. Wing has forged a very strong relationship with certain Filipinos of Chinese ancestry who are well placed in the government, and so the stink has been unavailing."

The second time through, the joker-moving part went quickly since one of the jokers started out on top. The King of Hearts ends up on the bottom, and hence on Randy's knee. That son of a bitch has a numerical index of 39, and so Randy has to count most of the way through the deck to reach the card in the thirty-ninth position, which is a ten of diamonds. He splits and swaps the deck, then puts the King of Hearts back on the bottom. Top card is now a four of diamonds, which translates to an index of seventeen. Counting the seventeen top cards into his hand he stops and looks at the eighteenth, which is a four of hearts. That works out to a value of 26 + 4 = 30. But everything here is modulo 26, so adding the 26 was a waste of time, because now he has to subtract it right off again. The result is four. The second letter in Enoch's ciphertext is S, which is the nineteenth letter in the alphabet, and subtracting four from that gives him O. So the plaintext, so far, is "DO."

"I get the picture."

"I was sure that you would, Randy."