The Book of Air and Shadows

by Michael Gruber

  “You cracked it already?”

  “Alas, no. But I have identified its type. Extremely interesting for a classical cipher, I believe, even unique. Shall I show? Or wait for after this excellent supper of your mother?”

  Mary Peg said, “Oh, please show us. I have to make a salad and we can eat the stew anytime.”

  With his usual diffident little bow, Klim left the room. Crosetti immediately caught his mother’s eye and rolled his own.

  “What?” she challenged.

  “Nothing. It’s just this is all pretty fast. We’re living here all by ourselves for years and all of a sudden we’re in a Polish movie.”

  Mary Peg made a dismissive gesture. “Oh, come on! He’s a dear man, and he’s really suffered-his wife died, he was in jail-Fanny’s been after me to meet him for years. You like him, right?”

  “Well, yeah. Obviously, not quite as much as you do. So…are you two…?” He rubbed his palms together, as if smoothing cream between them. She snatched up a wooden spoon and cracked him smartly on the crown of his skull. “You be careful, buster. I can still wash your mouth out with soap.” And they both laughed out loud.

  Klim came in on their laughter holding a thick sheaf of printer paper densely packed with lines of text and a legal pad covered with neat European pencilings. Klim sat down next to Crosetti and smiled politely. “We are having fun? Good. This also may be fun. So. You can see from my red eyes, I have been up most of this night with colleagues across the world and many have commented on this most fascinating cryptogram. So first of course we work Friedman’s superimposition. This is elementary, yes? We must distinguish the many different alphabets used in polyalphabetic cipher so we may do Kerckhoff ’s solution by frequency analysis; and we do this by superimposition of one string of ciphertext upon another to find coincidences; and if we have done this correctly, number of coincident letters will approach value kappa sub p or seven percent approximately. This is clear, yes?”

  “No. Maybe you could just skip to the bottom line.”

  Klim looked puzzled and began to riffle through the pages. “The bottom line? But the bottom line is enciphered like these others…”

  “No, it’s a figure of speech. I mean, please summarize your findings without all the technical jargon.”

  “Ah, yes. The bottom line. This bottom line is that we cannot do superimposition upon this cipher because the key does not repeat at all within the number of ciphertext characters we have available, which is 42, 466. Also, we find that the key has high entropy, much higher than expected for a running key from a book, so we cannot do simple analysis using common English words. So, either your man is not using an ordinary tabula recta, which I think highly unlikely, or he has discovered onetime system three hundred years earlier than Mauborgne did, in approximately 1918. Which also I cannot believe. There is no record of such a discovery. In fact, even the Vigenère cipher was not widely used. Most European intelligence services were satisfied with simple nomenclators until telegraphy came, and even afterward. There is no need for such very high security. It is a great flounder.”

  “You mean a fluke,” said Crosetti. “So if it isn’t a onetime system, what is it?”

  “Ah. I have a theory. I think your man started with a simple running key, from a book, as originally we thought. But I also think he was a very clever person and saw quickly how a running key from a book might be compromised through substitution. Now he might have changed his tabula into some mixed alphabet, in order to disguise common English digraphs like tt, gg, in, th, and so forth, but we do not think he did that. No, I think he merely combined two methods well known in those times. I think he combined a running key from a book with a grille. It is a way of easily generating a pseudorandom key of arbitrary length.”

  “Which means what? I mean as far as deciphering goes.”

  “Well, unfortunately it means we are stopped. As you know, onetime systems are unbreakable. Now, it is true that this is not a real onetime system. If we had ten thousand messages, I suppose we could make some progress, or even a thousand. But these few cryptograms are perfectly secure.”

  “Even with computers, brute force…?”

  “Yes, even with. I could show you mathematically-”

  “No, I got a C in algebra.”

  “Really? But you are intelligent person and it is so easy! Still, you will understand if I say it is like an equation with two unknowns, the unknowns being the key text and the ciphertext. Example: what is solution to x + y = 10?”

  “Um…x is one, y is nine?”

  “Yes. But also two and eight or three and seven, or one hundred and minus ninety, and so forth, an infinite number of possible solutions for such equations, and it is the same with onetime systems. To solve a cryptogram you must have a unique solution for each particular letter, no matter how it is disguised by multiple alphabets and keys. Otherwise, how to distinguish between ‘flee at once’ and ‘come to Paris’? Both can be derived from exact same ciphertext of a onetime system. Even if you capture some piece of plaintext you are still no better off because it is impossible to work backward from plaintext through ciphertext to determine what is key, because this key changes continually and is never used again. No, this is indecipherable, unless, of course, you have both the book he used and the grille.”

  “I thought we had the book. You said it was the Bible.”

  “I said probably the Bible. I have talked to Fanny of this and she says most probably they would have used the Geneva Bible edition of 1560 or later. This is the most popular Bible of that era, the Breeches Bible, so called, very common and also portable, nine inches by seven. The grille would be pasteboard or thin metal, perhaps punched out in a simple pattern to disguise secret use. Your Bracegirdle places the grille on pages he agreed on previously with control and copies out the letters that appear under these holes. This is his key. He copies out enough letters to encipher message and on the other end his control does the same, but in reverse. For the next message he uses another page. As I say, if we had millions of characters of ciphertext so that he must repeat same position of grille on pages, then we can solve by usual methods, but not as it is now. I am sorry.”

  He really looked sorry too, the sorriest Crosetti had ever seen anyone look, almost comical, like a sad clown. But at that moment, Mary Peg declared that supper was ready and plopped a huge tureen of steaming lamb stew down before them, and the expression on Klim’s face changed in an instant to utmost delight. Crosetti felt a little brighter himself. It always made him secure to be in a movie plot, and now, as he had mentioned to his mother, they were in a Polish movie: people bent almost to breaking under the weight of history and insolvable problems coming alive at the prospect of a warm meal.

  Toward the close of which, Klim returned to the subject they had avoided during the pleasant meal. “You know, I am baffled about one more thing,” he mused. “Why a cipher at all?”

  “What do you mean?” asked Crosetti.

  “Well, this man, your Bracegirdle, says he was spying on Shakespeare for the English government. Well, I too was a spy for the government and wrote reports, as did thousands of my countrymen. There are tons upon tons of these in archives in Warsaw and not one of them is in cipher. It is only foreign spies who use cipher. A Spanish spying on English people would use a cipher. Or if your man was abroad and sending messages back, then he would do the same. But government spies do not use ciphers. Why should they? It is governments who open mail, yes?”

  “They were paranoid?” offered Crosetti. “Maybe they thought that the people they were after could open mail too.”

  Klim shook his head, making his white crest wobble amusingly. “I do not think that is possible. Spies create secret messages, they do not decipher them. Ciphers and codes are used by governments only when they think other governments will read them. This cipher we have here-it is difficult to use, yes? Every letter must be enciphered by hand, and by a key that is quite laborious to generate. Why not simply w
rite it in clear and give to royal messenger?”

  “I know why,” said Mary Peg, after a wondering silence from the party. The men looked at her, the older with delight, the younger with dubiety, who said, “Why?”

  “Because they weren’t working for the government. They were plotting against the king and his policies. Didn’t you read all that business in Bracegirdle’s memoir about the Catholic match for the prince and how they were going to get King James to turn against the Catholics even more than he was already? I mean that was the point of all of it. They were going to destroy the theater and discredit the pro-Catholic policies in one blow. They couldn’t let anyone in the king’s party or administration find out what they were doing, and so they had to use this powerful cipher.”

  After some discussion, they agreed that this interpretation made good sense. Klim was particularly generous in his admiration. Mary Peg modestly attributed it to her Irish upbringing, in which she learned to look for the utmost in deviousness and perfidy among the English. Crosetti was impressed too, but not surprised, having been raised by the woman; but he was pleased to see that it had won the admiration of a secret policeman trained by the KGB. By that stage, the large jug of Californian red that had begun the evening nearly full was nearly empty. The talk now turned rather drunkenly to films. Klim told some Kiéslowski anecdotes, giving Crosetti fodder for any number of saloon conversations, after which Crosetti asked what Klim thought of Polanski. Klim sniffed, pulled thoughtfully at the tip of his nose, and said, “I cannot like him. I am not a friend of nihilism however beautifully done.”

  “That’s a little harsh, don’t you think? You said before that you thought Zanussi was too religious. Religion or lack of it isn’t the point. He’s a great director. He can tell a story on the screen with vivid characters and terrific pacing and mood. It’s like saying that if you like Rosemary’s Baby, you’re on the side of the devil.”

  “Are you not?”

  Crosetti was about to launch into an exposition of the pure aesthetics of film, but this answer to what he had imagined was a purely rhetorical statement checked him. He looked at Klim to insure that the man was serious, at his pale blue eyes, which certainly were, serious as fate. Klim continued, “If film or any art for that matter has not some moral basis then you might as well look at flickering patterns, or random scenes. Now I do not say what is this moral basis, only that there should be one. Pagan hedonism is a perfectly acceptable moral basis for a work of art, for example, as in Hollywood. Domestic bliss. Romance. It does not have to be…what is the word? Where the villain always dies and the hero gets the girl…”

  “Melodrama.”

  “Just so. But not nothing. Not the devil laughing at us, or not only that.”

  “Why not? If that’s the way you see the world.”

  “Because then art suffocates. The devil gives us nothing, only he takes, takes. Listen, in Europe, in last century, we decide we will not worship God anymore, instead we will worship nation, race, history, the working classes, what you like, and as a result of this everything is totally ruined. And so they said, I mean the artists said, let us not believe anything but art. Let us not believe, it is too painful, it betrays us, but art we trust and understand, so let us believe at least in that. But this betrays too. And also, it is ungrateful for life.”

  “What do you mean?”

  Klim turned to Mary Peg with a smile that quite transformed his face, showing her a faded image of the man he was when he knew Kiéslowski. “I did not expect to talk of such things. We should be in smoky café in Warsaw.”

  “I’ll go burn some toast,” said Mary Peg. “But what did you mean?”

  “So…this Polanski. He has had a horrid life. He is born at just wrong time. He is a Jew, his parents taken to death camps, he grows up wild. He makes success through hard work and talents and marries beautiful wife, and she is killed by some madman. Why should he believe anything but that devil rules this world? But I was born somewhat earlier in same time, not a Jew but still, life was not so happy for Poles either, the Nazis thought we were almost so bad as the Jews, and so I say I was, if not same as Polanski, at least, you agree, in the same class. Father murdered by Nazis, mother killed in uprising, 1944, I am on streets, a baby cared for by my sister, she is twelve years old, my first memory is burning corpses, a pile of bodies in flames and the smell. How we survived I don’t know, a whole generation of us. Later, I should add, like Polanski I lost my wife, not to a madman but also tortured to death, months of it. I was by that time not very well in with the authorities and it was difficult to obtain morphia for her. Well, not to talk about these personal troubles. I meant to say, after the war, somehow, despite the Germans and the Russians, we look around and discover there is still life in us. We learn, we make love, we have children. Poland survives, our language lives, people write poetry. Warsaw is rebuilt, every brick, same like before the war. Miloscz wins Nobel, Szymborska wins Nobel, and one of us is pope. Who could imagine this? And so when we make art, this art most often says something more than, oh, poor little me, how I have suffered, the devil is in charge, life is trash, we can do nothing. This is what I mean.”

  Crosetti considered this statement as much as he could, which was not very much, because he was an American and he wanted to make movies and sell them and he thought he had to at least be a tourist in the dark country. Suffering, nihilism, the devil laughing, all that Polanski stuff was a necessary spice, like oregano, not something you were expected to make a meal from. What he admired in the Poles was the competent surface, the camera movements, the way a face was lit, the way the camera dwelled upon a face.

  After a pause, he said, “So, anyway, do you want to watch some films?”

  “Not Chinatown please!” said Mary Peg.

  “No. We’ll watch moral art,” said her son. “We’ll have a John Wayne festival.”

  So they did. Crosetti owned nearly five hundred DVDs and several hundred videotapes and they started with Stagecoach and proceeded to hit the highlights of the Duke’s career. Mary Peg crashed halfway through She Wore a Yellow Ribbon, her head drooping against Klim’s shoulder. When the film was over, they settled Mary Peg on the couch with a blanket over her, turned off the set, and went back to the kitchen. Crosetti reflected that this was the first time in his memory that his mother had missed seeing the Tonight Show, and this produced in him a good feeling, as if she had won some kind of prize.

  “I too will go to bed, I think,” said Klim. “Thank you for a most interesting evening. I confess I have always liked the cowboy films. They are very soothing to me, like a lullaby when one is a child. Tell me, what do you intend to do about this cipher?”

  Crosetti was startled by the change of subject and then recalled that his father had said it was an old cop trick to get the suspect off balance.

  “I don’t see what I can do. You said the thing was uncrackable.”

  “Yes, but…your mother has told me this entire story, as much as she has of it, and so I know that a man has already died. Now you must think: the men who killed this professor do not know that the cipher is unreadable. Let us presume they have the Bracegirdle letter or a copy of it. This letter mentions other letters, ciphered letters. These they do not have and they must begin to want them and I am sure they must have obtained your name from the dead man. This young lady who was with you when you found them, she at least knows the ciphers exist. She has already disappeared, and sends a letter you suspect, which you are correct to do: anyone can write a letter, or force a letter to be written, and mail it from anywhere. She might be on the next street. Or dead as well.”

  Crosetti had considered that possibility any number of times and always dismissed it. Carolyn may have run away-from what he didn’t know yet-but he refused to admit that she might be dead. At some level he knew he was being infantile: people died, but not Carolyn Rolly. She was a survivor and good at hiding, and the script required that she reappear and conclude her business with Albert Crosetti.
A little Polish-movie business was okay, but not that.

  “She’s not dead,” he said, as much to hear the magic of the phrase as to communicate the thought to Klim. “Anyway, what’s your point?”

  “My point is that we are dealing here with violent people and there is no reason why they should not come after you next. You or your mother.”

  “My mother?”

  “Well, yes. I presume that if they have your mother you will give them anything they want.”

  An unwanted laugh sprang from Crosetti’s mouth. “Jesus, Klim! I think it was a mistake to let you watch John Wayne. They can have the damn things right now. I’ll put an ad out-‘thugs who whacked Bulstrode, pick up the cipher letters anytime.’”

  “Yes, but of course they would see that as a ploy. The problem with evil people is that they can see only evil in others. It is one of the worst curses of being evil, that you can no longer experience good. Believe me in this; for perhaps I have seen more evil people than you. Tell me, your father was a policeman-have you any guns in the house?”

  At this, Crosetti’s mouth fell open and he felt hysteria well up again but suppressed the feeling. “Yeah, we have his guns. Why?”

  “Because when you are gone it will be necessary for me to stay here armed.”

  “What do you mean, gone? When I’m at work?”

  “No. I mean when you are in England. You should immediately leave for England.”

  Crosetti stared at the man. He seemed perfectly calm, but you could never tell with a certain type of crazy person. Or maybe this was how he became when drunk. Crosetti was fairly drunk himself and decided to treat the current run of conversation like drunk-talk, or the type he and his friends got into when they were thinking about how to raise enough money to make a movie. He pasted a humoring smile on his face. “Why should I go to England, Klim?”

  “Two reasons. One is to disappear from here. Second is to find out what Bulstrode learned while he was there, if you can. Third is to find the grille.”