"Flash again!" he pleaded, and Schreuder repeated the signal. Suddenly a weak speck of light glimmered briefly on the top of the wall. Twice it showed, and then was extinguished.

"We can go on," whispered the priest excitedly, but Schreuder restrained him.

"What have you told those within the monastery who will help us to enter?"

"They have been told that we are spiriting away the Emperor and the Tabernacle to a safe place to save him from an assassination plot by a great noble of the Galla faction who seeks to take the crown of Prester John from him."

"A good plan," Schreuder murmured, and urged the priest down the bank to where the horses waited. Their guide led them onwards, and they climbed another deep ravine until they were beneath the massive, looming walls.

"Leave the horses here," whispered the priest. His voice was tremulous.

Schreuder's men dismounted and handed their reins to two comrades, who had been delegated as horse-holders. Schreuder assembled the raiding party and led them after the priest to the wall. A rope-ladder dangled down from the heights, and in the darkness Schreuder could not see to the top of it.

"I have kept my side of the bargain," muttered the priest. "Another will meet you at the top. Do you have the reward that I was promised?"

"You have done well," Schreuder agreed readily. "It is in my saddle-bags. One of my men will see you back to the horses and give it to you." He passed the end of the chain to his lieutenant. "Look after him well, Ezekiel," he said in Arabic, so the priest could understand. "Give him the reward he has earned."

Ezekiel led the man away, and Schreuder waited a few minutes until there was a grunt of shock and surprise out of the darkness and the soft rush of air escaping through a severed windpipe. Ezekiel returned silently, wiping his dagger on a fold of his turban.

"That was neatly done," said Schreuder.

"My knife is sharp," said Ezekiel, and slid the blade back into its sheath.

Schreuder stepped onto the bottom rung of the ladder and began to climb. Fifty feet up he reached a narrow embrasure cut back into the wall. It was just wide enough to squeeze his shoulders through. Another priest waited for him in the tiny stone cell beyond.

One after the other Schreuder's men followed him up and slid over the lintel, until all of them were crowded into the room.

"Lead us to the infant first!" Schreuder ordered the priest, and placed his hand on his bony shoulder. His men followed along the dark, winding passageways, each gripping the shoulder of the man in front.

They twisted and turned through the dark labyrinth, until at last they descended a spiral staircase and saw a glimmer of light ahead. It grew stronger as they crept towards it until they reached a doorway, on either side of which torches guttered in their brackets. Two guards lay huddled on the threshold, with their weapons laid beside them.

"Kill them!" Schreuder whispered to Ezekiel.

"They are dead already," said the priest. Schreuder touched one with his foot. the guard's arm flopped over lifelessly and the empty bowl that had held the poisoned mead rolled from his hand.

The priest tapped a signal on the door, and the locking bar was lifted on the far side. The door swung open and a nursemaid stood on the other side with a child in her arms, her eyes huge with terror in the light of the torches.

"Is this the one?" Schreuder lifted the fold of blanket and peered into the child's sweet brown face. His eyes were closed in sleep, and the dark curls were damp with perspiration.

"This is the one," the priest confirmed.

Schreuder took a firm grip on the nursemaid's arm, and drew her out beside him. "Now lead me to the other thing he said softly.

They went on, deeper into the maze of dark halls and narrow corridors, until they reached another heavy studded door before which lay the bodies of four priests, contorted in the agony of their poisoned deaths. The guide knelt beside one and groped in his robes. When he stood again he had in his hands a massive iron key. He fitted it to the lock and stood back.

Schreuder called Ezekiel to him in a whisper and placed the nursemaid in his hands. "Guard her well!" Then he stepped up to the door and seized the bronze handle. As it swung open, the traitorous priest and even the band of raiders shrank back from the brilliance of the light that flooded out from the stone-walled crypt. After the darkness the glow of a hundred candles was dazzling.

Schreuder stepped over the threshold, then even he faltered and came to an uncertain halt. He gazed upon the Tabernacle in its suit of radiant tapestry. The angels upon the lid seemed to dance in the wavering light, and he was struck with a sense of religious awe. Instinctively he crossed himself. He tried to step forward to lay hold of one of the handles of the chest but it was as though he had encountered an invisible barrier that held him back. His breathing was hoarse and his chest felt constricted. He was filled with an irrational urge to turn and run, and he recoiled a pace before he could check himself. Slowly he backed out of the crypt.

"Ezekiel!"he said hoarsely. "I will take care of the woman and the child. With Mustapha to help you, do you take hold of the chest."

The two Muslims suffered from no religious qualms, they stepped forward eagerly and seized the handles. The Tabernacle was surprisingly light, almost weightless. They bore it effortlessly between them.

"Our horses will be waiting at the main gate," Schreuder told their guide in Arabic. "Take us there!" They moved swiftly through the dark passages. Once they ran "unexpectedly into another white-robed priest, who was shuffling around an angle in the corridor towards them.