I showed him the openings surrounding us on all sides. ‘From the machicolations here they could launch rocks or oil over their foe, using these …’ Wooden platforms jutted out into space and we moved over to one now, holding on to upright supports either side and leaning out into the air to look down. Directly below us, the tower fell away to the cliff edge. Below that the shimmering river.

The blood draining from his face, Maffeo stepped back on to the safety of the tower floor. I laughed, doing the same (and secretly glad to, feeling a little giddy and sick myself, truth be told).

‘And why is it you’ve brought us up here?’ asked Maffeo.

‘This is where my story begins,’ I said. ‘In more ways than one. For it was from here that the lookout first saw the invading force.’

‘The invading force?’

‘Yes. Salah Al’din’s army. He came to lay siege to Masyaf, to defeat the Assassins. Eighty years ago, a bright day in August. A day very much like today …’

2

First, the lookout saw the birds.

An army on the move attracts scavengers. Of the winged variety, mainly, which swoop upon whatever scraps are left behind: food, waste and carcasses, both horse and human. Next he saw the dust. And then a vast, dark stain that appeared on the horizon, slowly beetling forward, engulfing everything in sight. An army inhabits, disrupts and destroys the landscape; it is a giant, hungry beast that consumes everything in its path and in most cases – as Salah Al’din was well aware – the mere sight of it was enough to move the enemy to surrender.

Not this time, though. Not when his enemies were the Assassins.

For the campaign the Saracen leader had raised a modest force of ten thousand infantry, cavalry and followers. With them he planned to crush the Assassins, who had already made two attempts on his life and would surely not fail a third time. Intending to take the fight to their door he had brought his army into the An–Nusayriyah mountains and to the Assassins’ nine citadels there.

Messages had reached Masyaf that Salah Al’din’s men had been plundering the countryside, but that none of the forts had fallen. That Salah Al’din was on his way to Masyaf, intent on conquering it and claiming the head of the Assassin leader, Al Mualim.

Salah Al’din was regarded as a temperate and fair-minded leader, but he was as angered by the Assassins as he was unnerved by them. According to reports, his uncle, Shihab Al’din, was advising him to offer a peace agreement. Have the Assassins with them, not against them, was Shihab’s reasoning. But the vengeful Sultan would not be moved, and so it was that his army crawled towards Masyaf on a bright August day in 1176, and a lookout in the citadel’s defensive tower saw the flocks of birds, the great clouds of dust and the black stain on the horizon, and he raised a horn to his lips and sounded the alarm.

Stockpiling supplies, the townspeople moved into the safety of the citadel, thronging the courtyards, faces etched with fear, but many of them setting up stalls to continue trading. The Assassins, meanwhile, began fortifying the castle, preparing to meet the army, watching the stain spread across the beautiful green landscape, the great beast feeding on the land, colonizing the horizon.

They heard the horns and drums and cymbals. And soon they could make out the figures as they materialized from the heat haze: thousands of them, they saw. The infantry: spearmen, javelinmen and archers, Armenians, Nubians and Arabs. They saw cavalry: Arabs, Turks and Mameluks, carrying sabre, mace, lance and longsword, some wearing chainmail, some leather armour. They saw the litters of the noblewomen, the holy men and the disorderly followers at the rear: the families, children and slaves. They watched as the invading warriors reached the outer curtain and set it ablaze, the stables too, the horns still blaring, cymbals crashing. Inside the citadel, the women of the village began weeping. They expected their homes to be next under the torch. But the buildings were left untouched, and instead the army came to a halt in the village, paying little regard to the castle – so it seemed.

They sent no envoy, no message; they simply made camp. Most of their tents were black, but in the middle of the encampment was a cluster of larger pavilions, the quarters of the great Sultan Salah Al’din and his closest generals. There, embroidered flags fluttered; the tips of the tent poles were gilded pomegranates, and the pavilion covers were of colourful silk.

In the citadel the Assassins mulled over their tactics. Would Salah Al’din assault the fortress or try to starve them out? As night fell they had their answer. Below them the army began work assembling its siege engines. Fires burned long into the night. The sound of sawing and hammering rose to the ears of those manning the citadel ramparts, and to the Master’s tower, where Al Mualim called an assembly of his Master Assassins.

‘Salah Al’din has been delivered to us,’ said Faheem al-Sayf, a Master Assassin. ‘This is an opportunity not to be missed.’

Al Mualim thought. He looked from the tower window, thinking of the colourful pavilion in which Salah Al’din now sat plotting his downfall – and that of the Assassins. He thought of the great Sultan’s army and how it had laid waste to the countryside. How the Sultan was more than capable of raising an even larger force should his campaign fail.

Salah Al’din had matchless might, he reasoned. But the Assassins, they had guile.

‘With Salah Al’din dead, the Saracen armies will crumble,’ said Faheem.

But Al Mualim was shaking his head. ‘I think not. Shihab will take his place.’

‘He is half the leader Salah Al’din is.’

‘Then he would be less effective in repelling the Christians,’ countered Al Mualim, sharply. He tired sometimes of Faheem’s hawklike ways. ‘Do we wish to find ourselves at their mercy? Do we wish to find ourselves their unwilling allies against the Sultan? We are the Assassins, Faheem. Our intent is our own. We belong to no one.’

A silence fell over the sweet-scented room.

‘Salah Al’din is as wary of us as we are of him,’ said Al Mualim, after reflection. ‘We should see to it that he is made even more wary.’

The next morning the Saracens pushed a ram and siege tower up the main slope, and as Turkish horse-archers made passes, showering the citadel with arrows, they attacked the outer walls with their siege engines, under constant fire from Assassin archers and with rocks and oil pouring from the defensive towers. Villagers joined the battle, pelting the enemy with rocks from the ramparts, dousing the fires, while at the main gates, brave Assassins made sorties through the wicket doors, fighting back infantry trying to burn them down. The day ended with many dead on both sides, the Saracens retreating down the hill, lighting their fires for the night, repairing their siege engines, assembling more.