The envelope contained three things.
A key - small, old, the kind that opens a safety deposit box or a post office box or possibly a diary, though Joshua had not seen a diary with a lock since he was eleven years old and his sister had one with a small brass clasp that he had not opened, being a child who was somewhat afraid of other people's interiors.
A slip of paper with an address in St. Louis. No name, no explanation. The street number and street name and the word Thursday written beneath it in his grandfather's hand, and beneath that a time: 7pm. No indication of which Thursday or how many Thursdays ago this had been written or whether it was a standing appointment or a single one.
And a photograph. Black and white, slightly overexposed, of four men standing in front of what appeared to be a church - not a grand one, a modest one, the kind with a small bell tower and a short flight of steps and a wooden door. The men were in ordinary clothes. None of them were in any kind of clerical dress. They were looking at the camera with the particular expression of men who have agreed to be photographed but are not entirely comfortable with it. His grandfather was on the far left, young - Joshua estimated the 1960s from the cut of the coats - and he was the only one of the four looking directly at the lens. The others were slightly angled away, as though they had turned toward each other just as the shutter opened, or as though they were more accustomed to watching than to being watched.
On the back, in the same small European hand: Praga, 1963. The custody holds.
Joshua stood in the basement for a long time with the photograph.
Then he went upstairs and made coffee.
He was not, by temperament, a man who panicked. This was partly discipline and partly disposition and partly - he had come to think - a kind of emotional economy he had developed in childhood in a house where one parent was unpredictable and the other managed that unpredictability by becoming very still. He had learned stillness early and thoroughly, and it served him well in most situations, and occasionally prevented him from responding to things that deserved a response.
He sat at the kitchen table with his coffee and looked at the three objects he had placed in a row on the table in front of him.
The key. The address. The photograph.
The custody holds. His grandfather, age perhaps thirty, in Prague in 1963. Behind the Iron Curtain. In front of a church with three other men who didn't want to be photographed, carrying a document - or at least a reference to a document - that connected to a journal that referred to an Ancient Order and a record that should not exist.
He was a historian of ideas. He spent his professional life tracking the way concepts moved through time, changed shape, accumulated meaning, got suppressed and resurfaced. He knew that the history of the past thousand years was littered with networks of people who had maintained something - a text, a practice, a memory, a flame - through periods when maintaining it was dangerous. He knew this with the professional detachment of a man who studied such things at a comfortable distance of several centuries.
He was less comfortable with the possibility that he was currently inside one.
He drank his coffee. It was good coffee. His grandfather had left behind an old stovetop Moka pot and a bag of Italian roast that was not yet stale, which was, Joshua felt, the most coherent communication he had so far received from the man.
The landline rang at eight forty-seven in the morning.
Joshua looked at it. It was on the wall near the refrigerator, a push-button phone from approximately 1987, avocado green, with a spiral cord that had been replaced at some point with a white one that did not match. He had not known it still worked. He was not sure why it would still work. He had assumed it was decorative in the way that certain old things in old houses are decorative - present not because they serve a function but because no one had gotten around to removing them.
It rang a second time.
He answered it because he was a man who answered phones, which is not as universal a trait as it once was.
"Joshua." Not a question.
The voice was old - genuinely old, not merely elderly - and carried the faint remainder of an accent he couldn't immediately place. Something European, worn smooth by decades of American English layered over it. The voice was calm in the specific way that very few people are calm, the way that suggested the calm was not an absence of feeling but a long practice of something.
"Who is this?" Joshua said.
"My name is Ambrose. I was a friend of your grandfather's. I have been expecting your call, but as you didn't call I thought I would call you instead."
"I didn't have your number."
"No," the man agreed pleasantly. "You didn't."
Joshua looked at the phone in his hand. "How did you get this number?"
"Teodor gave it to me thirty years ago. I'm glad it still works. I wasn't certain it would."
"Neither was I," Joshua said.
A brief pause, and he had the impression - irrational, he told himself - that the old man was smiling. "You found the basement."
It was not a question either. Joshua was beginning to notice that this man did not ask questions he already knew the answers to, which was either very efficient or slightly unnerving or both.
"Yesterday," Joshua said.
"And you found what was in the cabinet, and what was under the table."
"Yes."
"Good." Another pause, shorter. "Don't open the safety deposit box yet. The key is for a box at a bank in St. Louis. The address on the slip is not the bank - it's where I'd like to meet you, if you're willing. Thursday evening at seven. There will be others."
Joshua looked at the photograph still on the table. Four men in front of a church in Prague. The custody holds.
"Others," he said.
"Three others. As there generally are."
He wanted to ask what that meant. He found, unexpectedly, that he didn't. Some part of him - the historian part, he supposed, the part that knew how to wait for a document to yield its meaning rather than forcing it - understood that this was not the moment for that question.
"How did you know my grandfather?" he said instead.
The pause this time was different. Longer. Not evasive - thoughtful, as though the man were selecting among several true answers for the one that was most useful at this particular moment.
"We kept something together," he said finally. "For a long time. He kept his part and I kept mine, and we compared notes when we could, and when we couldn't we trusted each other anyway."
"What did you keep?"
"That," said the old man, with a warmth that Joshua would find himself thinking about later, in the way you think about something that named a thing you didn't know needed naming, "is exactly the right question. I'll tell you on Thursday."
He hung up.
Joshua stood at the kitchen wall with the avocado-green phone in his hand for a moment. Then he hung it up too.
He went back to the table. He looked at the key and the address and the photograph. He looked at the address for a long time - the street number, the street name, the word Thursday.
He picked up his own phone and opened the maps application and typed in the address.
It was a church.
Of course it was a church.
He put his phone face-down on the table and finished his coffee, which had gone slightly cold, and looked out the kitchen window at the Mississippi running high and fast between the houses at the end of the street, carrying as it always did in February the grey memory of everything that had passed through before.
He spent the rest of the morning in the study, going through the books.
They were in Polish and Latin and German and English and one shelf of French, organized - he began to see - not by language or subject or author but by something else, some principle he couldn't immediately identify. He pulled books out at random and put them back. He found marginalia in several of them, the same small precise hand, and once a loose sheet of paper tucked into a copy of Aquinas that turned out to be a letter in Polish that he couldn't read but which was dated 1987 and bore a postmark from Kraków.
He photographed everything with his phone, methodically, shelf by shelf.
He was a historian. This was what historians did with primary sources. They documented before they interpreted. They did not allow the excitement of encounter to rush them past the discipline of record. They took photographs and made notes and resisted the urge to skip to the conclusion, because in his experience the conclusion was almost never where you thought it was and the things you photographed dutifully and filed away without understanding were frequently the things that mattered most six months later when the picture had assembled itself.
He worked through lunch without noticing.
At some point in the early afternoon he found, on the bottom shelf behind a row of standing books, a flat wooden box he had missed the first time through the study. It was not locked. Inside, on a bed of faded green felt, was a compass - the navigational kind, not the drawing kind - old, brass, in good condition. Beneath the compass, folded carefully, a piece of paper. On the paper, in English this time, recent ink - the paper was not old: For when you are lost. And you will be lost. Everyone is, at first.
Joshua sat on the study floor with the compass in his hand for a while.
Then he put it in his pocket, which surprised him slightly. He was not usually a man who put things in his pockets on instinct.
He went back to work.