Recovering from their exertions, Altaïr and Al Mualim paused for a moment’s respite under a tree by the side of the gate of the Great Keep.

“That man—that wretch, Haras—you offered him a last chance to salvage his dignity, to see the error of his ways. Why?”

Flattered that his Mentor should seek his opinion, Altaïr replied: “No man should pass from this world without knowing some kindness, some chance of redemption.”

“But he shunned what you proffered him.”

Altaïr shrugged mildly. “That was his right.”

Al Mualim watched Altaïr’s face closely for a moment, then smiled, and nodded. Together, they started to walk toward the castle gate. “Altaïr,” Al Mualim began, “I have watched you grow from a boy to a man in a very short time—and I have to say that this fills me with as much sadness as pride. But one thing is certain: You fit Umar’s shoes as if they had been made for you.”

Altaïr raised his head. “I did not know him as a father. Only as an Assassin.”

Al Mualim placed a hand on his shoulder. “You, too, were born into this Order—this Brotherhood.” He paused. “Are there ever times when you—regret it?”

“Mentor—how can I regret the only life I have ever known?”

Al Mualim nodded sagely, looking up briefly to make a sign to an Assassin lookout perched high on the parapet wall. “You may find another way, in time, Altaïr. And if that time comes, it will be up to you to choose the path you prefer.”

In response to Al Mualim’s signal, the men in the gatehouse were winching up the castle gate again.

“Come, my boy,” the old man said. “And ready your blade. This battle is not won yet.”

Together, they strode toward the open gate, into the bright sunshine beyond.

Bright sunshine, a white light so strong, so all-encompassing, that Ezio was dazzled. He blinked to rid his eyes of the multicolored shapes that appeared before them, shaking his head vigorously to escape from whatever vision had him in its grip. He squeezed them tight shut.

When he opened them, his heartbeat had begun to settle to its normal rhythm, and he found himself once again in the subterranean chamber, the soft light returned. He found that he was still holding the stone disc in his hand, and now he was in no doubt at all about what it was.

He had found the first key.

He looked at his candle. He had seemed to be away for a long time, yet the flame burned steadily and had eaten up scarcely any tallow.

He stowed the key with the map in his pouch and turned to make his way back to the daylight, and to Sofia.

TWENTY-EIGHT

Excitedly, Sofia put down the book she’d been trying to read and ran over to him, but drawing the line at taking him in her arms. “Ezio! Salve! I’d thought you were gone forever!”

“So did I,” said Ezio.

“Did you find anything?”

“Yes, I did. Something that may interest you.”

They walked over to a large table, which Sofia cleared of books as Ezio produced the map he’d found and spread it out.

“Dio mio, how beautiful!” she exclaimed. “And look—there’s my shop. In the middle.”

“Yes. It’s on a very important site. But look at the margins.”

She produced a pair of eyeglasses and, bending over, examined the book titles closely.

“Rare books, these. And what are the symbols surrounding them?”

“That’s what I hope to find out.”

“Some of these books are really extremely rare. And a few of them haven’t been seen for—well—more than a millennium! They must be worth a fortune!”

“Your shop is on the very site of the trading post once run by the Polo brothers—Niccolò and Maffeo. Niccolò hid these books around the city. This map should tell us where if we can find out how to interpret it.”

She took off her glasses and looked at him, intrigued. “Hmmn. You are beginning to interest me. Vaguely.”

Ezio smiled and leaned forward. He pointed to the map. “From what I can see, from among the twelve titles, I need to find these three first.”

“What of the others?”

“That remains to be seen. They may be deliberate red herrings. But I am convinced that these are the ones to concentrate on. They may contain clues about the locations of the rest of these—”

He produced the round stone from his satchel. She donned her glasses again and peered at it. The she stood back, shaking her head. “Molto curioso.”

“It’s the key to a library.”

“Doesn’t look like a key.”

“It’s a very special library. Another has been found already—beneath Topkapi Palace. But, God willing, there is still time to find the others.”

“Found—by whom?”

“Men who do not read.”

Sofia grinned at that. But Ezio remained earnest. “Sofia—do you think you could try to decipher this map? Help me find these books?”

Sofia studied the map again for a few minutes, in silence. Then she straightened and looked at Ezio, smiling, a twinkle in her eye. “There are plenty of reference books in this shop. With their help, I think I can unravel this mystery. But on one condition.”

“Yes?”

“May I borrow the books when you’ve finished with them?”

Ezio looked amused. “I daresay we can work something out.”

He took his leave. She watched him go, then closed the shop for the day. Returning to the table, after collecting a number of tomes from the shelves nearby to help her, and a notebook and pens, she pulled up a chair and settled down at once to examining the map in earnest.

TWENTY-NINE

The next day, Ezio met Yusuf near the Hippodrome in the southeast quarter of the peninsula. He found him conferring with a group of younger associates over a map they were studying. The meeting broke up as Ezio arrived, and Yusuf folded up his map.

“Greetings, Mentor,” he said. “If I’m not mistaken, there’s a pleasant surprise in store. And if I’m not dead by this time tomorrow, we should have some good stories to trade.”

“Is there a chance of your being dead?”

“We’ve had wind of a plan the Byzantines are hatching. Now that the young Prince Suleiman has returned from the hajj, they plan to infiltrate Topkapi Palace. They’ve chosen this evening to make their move.”

“What’s special about this evening?”