Bizarrely, there had been no sign of the haruspex; only a reddened imprint in the sand remained where he had lain. A quick search of the area had revealed nothing either. Even with the glow from the lighthouse and the fire on the docks, there were plenty of places to hide among the boulders on the shore.

In some ways, Romulus had not been surprised by Tarquinius' disappearance. He still wasn't. He had had no further chance to search for his friend at the time. His only option would have been to desert, but, angered by the disappearance of one of his new recruits, Romulus' optio had placed a watch on him night and day. To make matters worse, the following afternoon Caesar's triremes had evacuated the entire army and sailed along the coastline to the east of Alexandria. Full of despair, Romulus was among their number. He'd tried to rally his spirits by imagining that Fabiola had heard his shout and would soon send word to him. It worked – partially.

Having learned a lesson in the Egyptian capital, Caesar had moved to meet his allies, who were led by Mithridates of Pergamum. Although he bore the same name as the king who had once tried Rome to its limits, Mithridates was no relation and was a trusted supporter of Caesar's. Comprised of Syrian and Judaean soldiers, his relief force had already encountered the main Egyptian army, which was commanded by the teenage King Ptolemy and his aides. After an initial setback, Mithridates had sent for help from Caesar, who was delighted to leave Alexandria's claustrophobic streets behind. His legionaries had all felt the same, with the obvious exception of Romulus. Not even a stunning victory against the Egyptians, when thousands of enemy troops died and the young king had drowned, could lift his mood.

With control of Egypt in his hands, Caesar returned to Alexandria, and Cleopatra, the king's sister. She had become his lover, so naturally, Caesar installed her as queen. Not that Romulus cared. Frantic, still heartbroken, he had resumed his search for Tarquinius. But weeks had gone by since the battle in the harbour, and whatever trail there might have been had long gone cold. In a city of more than a million people, what chance was there of finding one man? Borrowing whatever money he could from his new comrades, Romulus had spent it in the temples and marketplaces, hoping against hope he would discover something.

Not as much as a snippet.

Two months later, when the legions were leaving the city, Romulus had been in debt to the tune of a year's pay. I did my best, he thought wearily. There was no more I could have done.

Bucinae rang out, dragging Romulus back to the present. The call meant 'Enemy in sight'. At once the army ground to a halt. Thump, thump, thump went the fascines on the ground. Romulus looked to Petronius, who marched on the outside of the rank. After his heroism in saving the other's life, Romulus and Petronius had become firm friends. Petronius had even helped to look for Tarquinius, which Romulus was still grateful for. 'Can you see anything?' he asked.

Everyone was trying to see why they had stopped. There was a palpable hunger in most men's eyes. A battle would make a change from the boredom of the previous few months. Keen to establish his authority over all Rome's vassal territories, Caesar had first visited Judaea and Syria. Intimidated by his troops' mere presence, the local rulers had fallen over themselves to pledge their allegiance. With plentiful tributes collected, the legions' peaceful travels had continued with a voyage to Cilicia on the coast of Asia Minor.

Caesar had then headed for Bithynia and Pontus, where King Pharnaces was stirring up all kinds of trouble. A son of Mithridates, the Lion of Pontus and scourge of Rome twenty years before, Pharnaces was as warlike as his father. While Caesar and his men were trapped in Alexandria, he had raised an army and begun a brutal war against Calvinus, the Roman commander in the area. Inflicting heavy losses on Calvinus, Pharnaces' men had subsequently castrated all Roman civilians who fell into their hands.

Which was why Romulus and his comrades found themselves in a steep-sided valley in northern Pontus just after daybreak. Caesar did not take such affronts lightly, and after months without even a skirmish, his legionaries were feeling bored and restless. They were glad that Pharnaces' increasingly humble overtures of peace had been ignored. Now they were hunting down his army, intent on a confrontation. Caesar's plentiful Republican opponents in Africa and Hispania and political matters in Rome could wait until this matter was dealt with.

Hearing that the enemy was camped near Zela, Caesar led his legions north from the coast at a fierce pace, covering nearly two hundred miles in less than two weeks. It reminded Romulus of the last part of his fateful journey with Crassus' host. The obvious difference was that Caesar was a military genius, a title that his former ally certainly did not deserve. How could a disaster like Carrhae befall the general who foiled defeat and death at every turn? It felt good to serve under Caesar.

To reach Pontus, they had also marched through the province of Galatia. Deiotarus, its ruler, was a fierce, long-time ally of Rome but had supported Pompey at Pharsalus. Recently, he had begged for forgiveness of Caesar, which was duly given. Deiotarus' famed cavalry and ten cohorts of infantry were a welcome addition to the general's three battle-worn, understrength legions. Trained in the Roman manner, his troops were loyal and courageous.

Nearing Zela the day before, the combined forces camped to the west of the town. Deiotarus' Galatian horsemen had then reconnoitred the area, returning with news that Pharnaces' host was located a few miles to the north. Protecting the road to the Pontic capital, Amasia, it was positioned in the same place Mithridates had occupied when he defeated a large Roman army a generation earlier. Clearly this was deliberate, and while few legionaries regarded this as a good omen, they were not unduly worried either. Had Mithridates not succumbed to the Republic's might in the end?

'There!' cried Petronius triumphantly, pointing at the hill slightly off to one side. 'That must be it.'

Tying his chinstrap, Romulus stared at the flat-topped mount. It lay on the other side of an almost dry stream. Atop it, he could discern the outlines of hundreds of tents. The neighing of horses carried faintly through the thin air; mixed with the sound were the shouts of alert sentries. Soon figures began to emerge from the tents, and cries of alarm drowned out the previous noises. The legionaries began muttering excitedly. Their early arrival had caught Pharnaces' army by surprise.

Realising Caesar's tactic, Romulus chuckled. As he'd learned in the arena, knowledge and preparation contributed significantly to success in war, along with an unerring eye for swiftly taken opportunities. Caesar was master of all three. His order for every man to carry a fascine might have raised a few grumbles, but no one was seriously unhappy. When piled with others, they would form the core of a defensive earthwork.

Romulus wondered what else was in Caesar's mind. From Zela, the legions had followed the road to Amasia, which alternated on both sides of a low-running stream. At the moment, they were on its eastern bank. The watercourse that he could see below the enemy-occupied hill was probably an offshoot of it too, but neither were deep enough to prevent them getting to grips with their opponents. A short distance in front of their position, the valley split, forming a rough 'T' shape. The stream below Pharnaces' army emerged from the left arm, while the road continued due north, over the hills. No one could take this route without risking a flank attack from the enemy. Not that Caesar would try to avoid battle, he thought.