"It is too late for Sir Fornarini or anyone else, for that matter, to come to our aid." He pulled Fra Prospero away from the wall as the first arrows whirred past them. "The main force has circled around from behind. That's why it took them days to reach us." They ran down the steps into the interior. "They're already inside, otherwise this group would not have shown themselves."

"Impossible! I refuse to believe-"

"Quickly!" Fra Leoni snapped his fingers. "Your key!"

The Magister Regens dug in his robes, but Fra Leoni grabbed it from his fist, tore it off the chain to which it had been attached to a wooden crucifix. It lay in his palm, a key like no other, save its twin, which he possessed. It had a strange burred end and along its length seven starlike notches of different depths and widths.

The Magister Regens dug his clawed fingers into Fra Leoni's robes. "Your insolence will be your downfall one day."

"Mayhap," Fra Leoni said. "But not today."

Without taking his gaze from the obsidian eyes, he lifted one hand up and slowly, finger by finger, freed himself from the other's grip. "Today your heartfelt prayers go with me, Magister Regens, for I am the sole Keeper of our secrets now. If I die, the Order dies with me."

All at once, shouts rose from below, the sound of steel whistled through the air, cries and terrible groaning.

"Now you have your proof," Fra Leoni said tersely. "We have been betrayed again. Our citadel has been breached."

Fra Prospero's eyes flickered with a tiny stirring of fear. His bearded face glistening, he drew himself back to the urgent conversation. In a lowered voice, he said, "And what of the one secret-the one that dwarfs all others, the one even those who come, even he who sent them, are unaware of? Will it be safe with you?"

"It is why I was ordained Keeper. The trust is sacred; it can never be broken. I guard them all with my life, the one secret especially."

Fra Prospero nodded. If he was not pleased, then he was at least satisfied. He had to be; he had no other choice. "Then God go with you, my son. In Christ's name, be safe."

"And if we both survive, you know where to meet me."

"Within a year," Fra Prospero said. "Yes."

"Then we will see each other again, and resume our debate."

"God willing," Fra Prospero said.

Tucking the hem of his robe into his belt, Fra Leoni went down the western spiral staircase. Where the blood had dried, the fabric had become stiff and uncomfortable. Passing the first in a line of windows, he could see the darkening stain of night climbing upward into the cobalt vault of the sky. Closer to hand was the brief sloped ridge of the kitchen's tile roof and, beyond, the pillared terraces of the royal wing. An evil flicker of light caught his eye. Someone had started a fire close to the walls.

Just below, he encountered fighting, already at a fierce pitch. Seeing two of his brothers under attack by four Knights, he drew his weapon and threw himself into the fray, beating back a Knight who had come close to cleaving Fra Benedetto's skull in two. This was not what he should be doing. His first and only duty was to save himself and, in so doing, keep the cache of secrets safe. The trouble was, he could not help himself. His brethren were in dire straits; how could he leave them?

He parried a blow weakly, giving his opponent a false sense of his prowess, then as the Knight recklessly stabbed at him, he neatly knocked aside the strike, drove the point of his sword through the other's midsection. Another Knight attacked on his right, and he sliced through the enemy's wrist. But now six more Knights leapt up from below, and he was forced to leave the defense to the others, retreating back up the stairs to the level of the trefoil window. He beat back the broadsword thrust of a Knight who had broken away from the pack to bring him down, struck what seemed a rather awkward blow with the flat of his sword. It had the desired effect, throwing off the Knight's balance. And while he was thus at a disadvantage, Fra Leoni kicked him hard in the shoulder. The Knight spun, his booted foot missed the edge of the step, and he tumbled heavily backward into two of his compatriots.

Fra Leoni took this moment and, gaining the stone sill of the window, leapt out onto the tiles of the kitchen roof. From here, he could see into the lower courtyard, swarming now with Knights of St. Clement. He could see the wall that had been permanently smoke-blackened by Saracen siege fires. Betrayed, he thought bitterly, from within our most sacred inner sanctum.

Then a crossbow bolt passed not a foot from his head, and he dove to his left, stretched fully on the tiles. As soon as he raised himself on one elbow, another bolt was loosed at him, though he could not make out the bowman. Not that it mattered; his antagonist was far outside his reach.

Flattening himself again, he contrived to pull himself across the tiles. His intention had been to gain the kitchen below, and thence out a passage beneath the stone flooring. But one glance at the bloody chaos that had overtaken the courtyard told him he would never make it to that section of the lower floors, let alone to the kitchen. That being the case, he needed to gain the library. He changed direction, scuttling back up to the crest of the kitchen roof. This had the disadvantage of making of him an excellent target for the three or four seconds it would take him to heave his body across the crest and down the other side to the eastern wing of the monastery's belly.

There was no help for it; no other way presented itself for him to get to the library. But he needed to lengthen his odds, he needed a diversion. Just below the crest, he waited, gathering himself, slowing his breathing. He searched with his free hand until he found a loose tile. Ripping it from its moorings, he launched it into the air in the opposite direction from which he intended to go. He heard it shatter onto the cobbles of the courtyard below, heard the shouts of the Knights raised in warning. Immediately, he rolled over the top, onto the eastern side of the roof. No crossbow bolts followed him and, without pausing to catch his breath, he made his way as quickly and unobtrusively as he could, at length swinging down onto the library terrace. On his way down, he had disturbed a bird's nest and, knowing he might not get another chance at sustenance for some time, he ate the three eggs, for once his scent was on them the mother would no longer sit on them but would cast them out, just as his Order was being expelled from the bosom of the Church.

He went quickly through the room, filled with shelves of precious volumes. Even now he was terrified that the Knights would set fire to the monastery and all this knowledge would be lost forever.

Fra Leoni cautiously stepped from room to room, moving ever eastward. He needed to gain the eastern wall. From time to time, like the tide rushing recklessly onto hard shingle, he heard an upsurge in the terrible sounds of war that set his teeth on edge-the clash of steel on steel, the animal grunts of warriors straining one against the other, coarse oaths and the deep groans and cries of those wounded or near death.

In the semidarkness, he at last reached his goal, the eastern wall, which was entirely tiled in a bewildering Greek pattern. He felt with callused fingers for the mechanism that would allow him entry to the hidden stairs-a tile, fifth from the floor, third from the left-and was about to press it when a sound came to him, both low and sharp. He froze and allowed his senses to quest outward. At first nothing, then it came again, the scrape of steel against stone. Someone was in the chamber with him. But instead of attacking, he was watching and waiting.

Fra Leoni quelled his instinct to open the door and flee. He could not let the enemy know of this escape route, for if he did, the Knights would come after him with everything they had.