The Blackthorn Key

“Wait here,” he said. “I’ll tell the masters you’ve arrived.” I stepped inside. He closed the door behind me, the latch clacking shut.

So this was Oswyn’s office. It was tidy—I’d expect that from a Puritan—but smaller than I thought it would be. A simple desk was in the center. An uncomfortable-looking wooden chair sat behind it, its back to the courtyard window. An identical chair faced it. The desk was covered with neatly stacked papers, one sheaf stained with oil that had leaked from an unlit lantern perched on the nearby corner. The plaster walls were stark and colorless, undecorated except for a series of vellum pages pinned to them, some with writing, some with drawings of various figures and icons. A handful of empty pots were arrayed on one side, half a dozen books on the other.

I sat in the chair opposite the desk and waited. There was a curious sketch on the wall beside me. Two men and two women rode magical beasts: a griffin, a manticore, a centaur, and a winged horse. Each figure was labeled in Latin with one of the four elements, the building blocks of all creation. Aer, ignis, aqua, terra. Air, fire, water, earth.

The beasts in the drawing reminded me of the mural below the Mortimer house. I thought of the lock hidden behind it, the crypt under the sarcophagus, the statues of saints in the alcoves.

Secrets under secrets, I thought. Codes inside codes.

The Cult of the Archangel had begun its murderous campaign four months ago. One month later, Master Benedict had shown me the book of saints. At the time, I’d been confused. Catholic saints?

“It’s important to understand history,” my master had said. “You never know when you’ll need it.” And I had.

Then he gave me my puzzle cube. It wasn’t just an incredible birthday present. It was a lesson in symbols, and liquid keys. I’d seen those, too, in the mural below the crypt.

Now I understood.

He’d been training me. Even in secret, Master Benedict had never stopped training me. He’d wanted me to find the chamber in the crypt. He’d led me every step of the way. To do that, he’d taught me everything I needed, except one essential thing: what the symbols in the mural meant.

He had to know I didn’t understand them. He wouldn’t bring me to the edge and just leave me there. He must have given me the solution.

It had to be in the message in the ledger.

I put my ear to the keyhole in Oswyn’s door and listened for a moment. Hearing no footsteps, I returned to the desk and pulled the ledger paper and scrap from under my master’s sash.

That line. That one line I couldn’t understand.

JSYYAALYUFMIYZFT

What had I missed? I looked at the original message, the whole thing together.

?Δ esid. A: rapf. O set. age Htsn. oil eh. two leb. Ht4: shg. Uh. ← ↓M08→ 05142020222207201601080420210115 end.swords neminidixeris Each line hid something different. The first, with the sword and triangle I didn’t understand, told me how to find the crypt, where I’d seen similar symbols I didn’t understand. The last line was the warning, in Latin, to keep it secret.

That left the middle line, from which Tom and I had generated the jumble of letters. The key to deciphering the symbols had to be in there. It occurred to me that we hadn’t yet figured out what “end.swords” meant. It had to be related to what came before.

End swords. How would that help me decipher the code?

I’d seen a lot of swords lately: the symbol on the first line of the message, the angel statue in the mausoleum, the mural on the iron door below. Had I overlooked something on one of them? Was there another sword somewhere I hadn’t found?

I shook my head, feeling like I was missing the point. Swords didn’t make any sense here. This line was a cipher. It hid words.

Ends words. End’s words.

End’s words? What words? What end?

Of the message?

What was special about the end of the message?

Nemini dixeris, it said. Tell no one.

I thought about it. It was a warning. It was two words, written as one. It was in Latin.

Latin?