Will tapped Tug on the shoulder and, as the horse rolled upright and came to his feet, he stepped astride him so that they came up together. With the sound of Tug's hoof beats now screened by the ridge between him and the Genovesan, he took the opportunity to urge the horse into a gallop. When they came over the crest, he would expect to be only a few hundred metres from the other rider.

This time, he didn't pause at the crest. It was time to commit. They had been travelling for almost four hours and logic told him they must be close to the Genovesan's goal. They crested the rise at a full gallop and Will gave a small cry of surprise.

Tug's ears went up at the sound but Will hurriedly reassured him.

'Keep going!' he said. The little horse's ears went down again and he maintained his gallop, never missing a beat.

Before them, the landscape had changed. The series of undulating ridges now gave way to a long, gradual slope leading down until it opened out into a wide, long valley. Tennyson's camp was visible, some three kilometres away. The numbers had grown from the twelve or fifteen people who had been with him originally. Now, he estimated, there must be a hundred people gathered there.

But Will's more immediate problem was the Genovesan, now less than two hundred metres ahead of him. He couldn't believe his luck. The assassin hadn't heard the thudding of Tug's hooves on the grass. He continued at a slow walk, his horse plodding heavily.

Then Will saw the man's head jerk up and turn towards them as, inevitably, he heard them. Will was close enough to hear his sudden shout of surprise and saw him put his heels into his horse's ribs, rousing it to a lumbering canter, then a weary gallop. It was a tactical mistake, Will thought. The shock of seeing him had startled the man into an error. Armed with a crossbow, he would have been better to dismount and face his onrushing pursuer.

But then, he wasn't aware that Will needed to take him alive. Perhaps he wasn't ready to face the Ranger's phenomenal accuracy and speed once more. He must be aware that only luck had saved him in their previous encounter.

Will saw the pale oval of the Genovesan's face as he glanced over his shoulder. Tug was closing the range rapidly now and the man was kicking desperately with his heels to spur his own horse on. But the lumbering farm horse never had a chance to outrun the fleet-footed Ranger horse and Tug was gaining with each stride.

The Genovesan struggled now to unsling his crossbow. As he saw what the man was doing, Will shoved the joined strikers through his belt and unslung his own longbow. The Genovesan's hand went to his quiver, selecting a bolt and placing it in the groove of the crossbow. Will's throat constricted and his mouth went dry as he realised he was about to face one of the man's deadly poisoned bolts. Under normal circumstances, he would have shot first. All the advantages were on his side. The other man had to twist in the saddle to get off a shot, while Will could shoot straight over Tug's ears. At this distance, he could pick him off easily.

But he needed the man alive.

The Genovesan had finally managed to load the bolt. He turned awkwardly, fighting against the jolting, uneven gait of his horse, to bring the crossbow to bear. He was twisting around to his right, so Will guided Tug with his knees, veering him to the left, forcing the Genovesan to twist further, making it more difficult for him to take aim.

The Genovesan realised what he was doing and swung suddenly the other way, twisting round to his own left for a clearer shot. But as soon as he did, Will zigzagged again, taking Tug back to the right. The manoeuvre was successful. The Genovesan found that his target was again out of sight. And Tug had closed the range by another twenty metres in the process.

The Genovesan twisted right again. This time, Will kept galloping steadily, without zigzagging. But now he had an arrow nocked and rode with the reins dropped on Tug's neck, guiding the horse with knee signals. He couldn't risk killing the Genovesan, but his quarry didn't know that. The assassin would get one chance for a shot. There wouldn't be time for him to reload, even if he could manage the task on horseback.

When he came to shoot, Will planned to spoil his aim. He was confident that he could loose several arrows in rapid succession, putting them close enough to the Genovesans' head to make him flinch. He remembered the duel with the man's compatriot. These men were primarily assassins, used to shooting from cover at a helpless target, someone who was unaware of their presence. They weren't used to open combat, facing an enemy who shot back – and who shot with deadly accuracy.

He was closer now. Tug's gait was smooth and controlled, unlike the farm horse, who was clumsy and tired and had the Genovesan bouncing unevenly in the saddle.

Here it came! The crossbow levelled and he saw the Genovesan's hand begin to tighten round the trigger lever. Will's hands moved in a blur, drawing, releasing and flicking a new arrow out of the quiver and onto the string in such rapid succession that he had three arrows in the air in the seconds before the Genovesan released.

As his hand tightened on the crossbow's trigger, the assassin suddenly became aware of the danger. Something hissed viciously past his head, seemingly only a few centimetres away. And he was aware that two more shots were on the way, a fraction of a second behind the first. It would have taken far more steady nerves than he possessed to hold a cool, deliberate aim – even if he weren't being jolted and jounced by the galloping horse. He ducked, shouting an involuntary curse, and his hand spasmed, jerking hard on the trigger lever and sending the bolt arcing high into the air, so that it fell harmlessly into the long grass nearly a hundred metres away.

The danger was past. Will tossed the longbow aside. There was no time to re-sling it and he could recover it later. He drew the strikers from his belt and urged Tug to one last burst of speed. The assassin, seeing him only forty metres away, drummed frantically with his heels in his horse's ribs. The exhausted animal had slowed to a trot while his rider had been preoccupied and now he needed speed again. The horse responded as much as it could but Tug was eating up the distance between them now. Too late, the assassin began to reach for one of the many daggers he carried. But Will's right arm went up and then came forward in a smooth, powerful throw.

The strikers glinted in the sunlight as they spun end over end. For a second, the assassin didn't see them, didn't register the danger. Then he saw the spinning metal and ducked low over his horse's neck.

The man had reflexes like a cat, Will thought. The strikers spun harmlessly over his head and disappeared into the long grass. Will cursed. He'd never find them again. He dragged his saxe from its scabbard.

'Go get him, Tug,' he said and felt the response from his horse as he accelerated once more, now moving as fast as Will had ever felt him move.

He saw a glint of steel in the Genovesan's hand, recognised it as one of the long-bladed daggers the assassins carried. He held the saxe ready, and drove Tug forward. The Genovesan started to turn his horse to meet the charge but he was too late. He struck once, aiming for Tug, but Will leaned forward over his horse's neck and deflected the thin blade with his saxe.

Then Tug's shoulder smashed at full speed into the exhausted, off-balance farm horse and sent him crashing over, so that he hit the ground on his side and slid for several metres along the slick surface of the grass. The violent movement trapped the Genovesan's right leg under the horse's body. The horse's hooves flailed weakly in the air but it made no attempt to rise. It was finished.

Instantly, Will was out of the saddle. He ran towards the trapped assassin. The Genovesan had lost his dagger in the collision and was scrabbling frantically under his purple cloak to draw another. Without a second's hesitation, Will stepped in and slammed the heavy brass-shod hilt of his saxe into the side of the man's head. Then, without waiting to see if the first blow had been successful, he repeated the action, a little harder.