I couldn’t really argue with that. Not knowing what he thought was frustrating, yes, but his reasoning made a lot of sense. In fact, the spymaster had begun to remind me of Master Benedict—and not just because he could be a bit strange sometimes, too. He’d also cautioned me against jumping to conclusions.
“What about the cipher?” Walsingham said.
“I’m pretty sure it’s Vigenère,” I said, “but I haven’t been able to figure out the key.”
“You’re familiar with Vigenère, then?”
“Yes, my lord. My master taught me. Master Benedict, I mean.”
“I understood. The key, or the message—can you tell me anything about them?”
The way he asked made me think he already knew something. “No, my lord… Can you?”
“Yes.” I half expected him to say again he wouldn’t tell me what. Instead, he said, softly as ever, “Sit at my desk.”
I did.
“In the drawer to your right, you will find a quill, ink, and paper. I want you to do an exercise.”
Another test? Inwardly, I sighed, but I did as he commanded. I also took the paper with the Vigenère square out from under my apothecary sash.
He looked at it briefly, then nodded in approval. “I want you to encode a simple message. A single word: ‘the.’ ”
I felt like saying That’s it? But dutifully, I wrote it down. “And the key?”
“The same word.”
“ ‘The’ again?”
“Correct.”
I wrote it out, the key over the message.
T H E
T H E
“Encode it,” the spymaster said. “And do it out loud.”
This seemed awfully pointless, but, title or not, he was my master now. “To encipher something,” I said, “we start with the first letter of the key, T, in the row, and the first letter of the message, T, in the column. Then go down and across, and we get… M.”
“Next we match the second letters,” I said. “H with H gets… O. Finally, E with E makes… I. So all together, we get MOI… wait.”
T H E
T H E
M O I
“MOI,” I said, surprised. “That’s the first three letters of the code!”
M O I U R H J B X A M G X B H B L L
“So it is,” the spymaster said. “And we see our mystery messenger has made a mistake.”
Walsingham stood and came around to my side of the desk. “Vigenère is said to be unbreakable,” he said. “Le chiffre indéchiffrable, they call it: the indecipherable cipher. So far, that has proved to be correct. But even with an unbreakable code, we may find clues. For where the code succeeds, sometimes people fail.
“It is not uncommon to start a message with the word ‘the.’ It is also not uncommon to use a key that begins with the word ‘the.’ If the codemaker does both of these, then the first three letters of the message will always read the same: M, O, I. And he will have given away part of what he is trying to hide.”
“How did you discover this?” I said, amazed.
“I have spent my lifetime studying codes. Much failed hunting, a few gems unearthed. At any rate, knowing something about the key may prompt the decipherer to realize…”
He went on talking, but I wasn’t listening. I stared at the message, and the code, and the exercise I’d just finished. Then I sprang from my seat.
“I know,” I said. “I know what the key is.”
CHAPTER
15
THE SPYMASTER STUDIED MY FACE. “Do tell.”
“It’s here,” I said. “Right here in the message. I can’t believe I didn’t see it.”
I turned the letter I’d received toward him.
“The instruction, before the code. It says, ‘You will know the key when you see the truth. Remember Paris.’ I thought they were talking about what happened in France: the assassins, or their search for the lost Templar treasure, something like that. But when we were in Paris, trying to solve the riddles, Tom pointed something out.
“He noticed that for all the old clues the Templars left, the solution was always literal. That is, you’d think the puzzles were confusing, but if you read each clue exactly as written, you’d understand what they really meant.
“So let’s do the same. Take this line literally. You will know the key when you see the truth.”
And I circled the words.
You will know the key when you see
the truth. Remember Paris.
“When you see… ‘the truth.’ ” Walsingham raised an eyebrow. “Fascinating.”
He motioned for me to try it. I wrote the code out, the key THETRUTH above it. Then I got to work. Even after only half the code, I knew I’d found what we were looking for.
T H E T R U T H T H E T R U T H T H
M O I U R H J B X A M G X B H B L L
T H E B A N Q U E T I N G H O U S E
“The Banqueting House,” I said.
“Do you know where that is?” Walsingham asked.
“It’s part of the palace. Just outside.” I frowned. “But what does it mean?”
“I suppose you’ll have to go find out.”
I looked at him, surprised. “You’re not going to take over?”
“Why would I?”
“Well… you’re the m—you’re in charge. I just thought…”
“This message was not meant for me,” the spymaster said.
“You still solved it.”
“No. I recognized a pattern, and educated you. The solution was in your head, not mine. Only you knew the secret of Paris.” Walsingham pushed the letter toward me. “Whoever sent you this appears to be trying to help. They have chosen you as their contact. I see no reason to replace you. I suspect they would not even permit it.
“If you need my assistance, you may come to me, any time, day or night. I will not be here today; there are matters I must attend to at the docks,
