Lion of the Sun

PART FIVE

Capax Imperii (The East, Winter AD260-Summer AD261)

'The ways of the gods are slow, but in the end their power is shown.'

Euripides, Ion, 1615

Up on the dais in the palace in Antioch, the chief men of the imperial entourage were in place. The two youthful emperors, Macrianus the Younger and Quietus, were enthroned. To their left, their father, Macrianus the Lame, sat on a curule chair nearly as high and nearly as elaborate as the thrones. There were no other chairs. Beyond the father was the spymaster Censorinus, backed by the imperial secretaries. To the right of the emperors stood Maeonius Astyanax, the senior Praetorian Prefect; Ragonius Clarus, the Prefect of Cavalry; and, on the end, as the other Praetorian Prefect, Ballista.

A gust of rain rattled against the windows of the great apse. Outside, it was a cold and grey midwinter morning in Antioch. I am getting soft, thought Ballista: back home in Germania this could pass for mild spring weather. Where Calgacus comes from, this is probably a balmy summer's day.

The ab Admissionibus drew back the hangings at the far end of the big room. Blinking a little in the many lights, the governors who supported the Macriani entered: Piso of Syria Coele, Cornicula of Syria Phoenice, Pomponius Bassus of Cappadocia, Achaeus of Palestine, Virius Lupus of Arabia, Mussius Aemilianus of Egypt, Theodorus of Cyprus and Trebellianus of Cilicia. With them was Sampsigeramus, the client king of Emesa.

Nine powerful men, but it was interesting who was not there: no governors west of Cilicia – above all, not Maximillianus of Asia; and from the east, no Aurelius Dasius of Osrhoene nor, most crucial of all, Odenathus Lord of Palmyra. Certainly all except the Lion of the Sun had sent excuses: illness, bandits or barbarian raiders. It could mean a great deal, or nothing. Politics in the imperium, when the stakes were as high as this, never admitted an easy reading.

The next wave of the consilium was ushered in – some forty senators, headed by the ex-consul Fabius Labeo, the nobilis Astyrius and a relative of the Macriani called Cornelius Macer. It was impressive. Admittedly, long ago, more had fled east to join Mark Antony in his doomed campaign against Octavian. Yet the imperium was now divided three ways between Gallienus, Postumus and the sons of Macrianus. To assemble so far from Rome about one in twelve of all senators was impressive.

The final group was shown in – a huge throng of equestrians, almost all junior military officers: prefects, tribunes and the like. Among them, the bright-red hair of tall Rutilus stood out. Ballista also caught sight of the pointy face of Castricius. The latter winked. He had come a long way since being a slave in the mines.

At a sign from the ab Admissionibus, the members of the consilium performed proskynesis. As he got up, Ballista saw that Macrianus the Elder had merely leant a little forward and blown a kiss. The lesser form of adoration could be put down to his age and incapacity, but it could be interpreted as something very different.

When the comites were back on their feet, the senators looked around, trying not to give evidence of their surprise and displeasure at the lack of seats. Ballista could see what the regime was attempting: trying to mark the emperors out yet more from their most powerful subjects, to enhance even further their dignity. But it was a potentially dangerous ploy. All too easily it could smack of arrogance, or even oriental despotism. A real emperor could sit cross-legged on the ground eating porridge with his legionaries and not lose dignitas.

Laboriously, Macrianus the Elder hauled himself to his feet. Leaning on his walking stick, he pulled a fold of his toga over his head. In a firm voice, he prayed for all the immortal gods, all the natural gods of Rome, to guide their deliberations, hold their hands over the emperors and their consilium. The flame burned blue-green as he sprinkled a pinch of incense over the sacred fire.

Regaining his seat, Macrianus indicated that Maeonius Astyanax should hold the floor. The senior Praetorian Prefect cleared his throat. The air was thick with incense and perfume, although it did not quite cover the bitter reek of burning which still lingered from the Persian sack.

'Most noble emperors, members of the consilium, I bring good news.' Astyanax paused. The lights made deep shadows in the lines on his forehead and under his fleshy mouth. His face was inscrutable.

'Only a short time now stands between the degenerate tyrant Gallienus and his death. He fritters away what little is left with prostitutes and pimps, barbarians and buffoons – dressed as a girl, submitting as a girl, mocking the dignitas of the throne and the maiestas of the Roman people.'

Ballista knew that Astyanax, revelling in his orotundity, could keep this up for hours. Some of the usual phrases of invective floated through his thoughts – 'more unnatural than Nero', 'crueller than Domitian', 'more perverse than Heliogabalus'; 'incest and magic'; 'the profligate', 'the coward', 'the enemy of men and gods'. Rain beat on the windows.

'Now the forces of righteous retribution are ready to march.' Astyanax's words brought Ballista's attention back. 'The minor troubles of a few days ago are a thing of the past. It was nothing more than the almost commendable over-eagerness of a handful of troops from the west to free their contubernales and families from the perverted lusts of the tyrant.'

Which, Ballista thought, was a good way of describing a serious mutiny – one only defused by a large donative of cash to the mutineers and a complete capitulation to their demands: yes, the western troops could begin their march home as soon as it was spring, some even sooner.

'Here in the east all is secure. The cities of Carrhae and Nisibis, recovered from the Sassanids by Odenathus, have been handed over to the governor of Osrhoene. Setting them in order, of course, accounts for the absence of Aurelius Dasius from this gathering today.'

It might, thought Ballista.

'I have received a letter from Odenathus himself.' Astyanax produced a piece of papyrus from his scabbard. It neatly reminded his listeners that he, with Ragonius Clarus and Ballista, was one of the three men allowed to go armed in the presence of the emperors.

'The Lord of Palmyra will take the war to the Persians. He has the Sassanids on the defensive. The Lion of the Sun intends no less than to sack Shapur's capital of Ctesiphon. He expresses his complete confidence that the gods will settle the rule of Rome on those they favour.'

Astyanax flourished the letter before returning it to his scabbard. Ballista saw no more than that there was writing on it. He would not have been surprised had it been blank.

'In view of Odenathus's signal loyalty to Rome, our noble emperors have sent him magnificent presents from among the property justly confiscated from the atheist Christians.'

A large bribe, thought Ballista, tortured out of the adherents of a supposedly peace-loving sect in response to a wonderfully ambiguous message. The northerner made sure his face was immobile.

With a grandiloquent gesture, Astyanax turned to the emperors. 'Domini, the east is secure. Give the word and we will follow you to Rome to free the imperium from the cruel tyranny of Gallienus. Just give the word.'

In the murmur of approval, Ballista saw Macrianus nod to one of his sons.

Macrianus the Younger held up his sceptre for silence. 'We thank the Vir Ementissimus Maeonius Astyanax. We hear the wishes of our comites. We hear the prayers of those oppressed in Europe and Africa. In the spring, as soon as the campaigning season opens, we will march to the west.'

Now he had all their attention.

'I myself, accompanied by my father, the Prefect of Cavalry Ragonius Clarus and the Princeps Peregrinorum Calpurnius Censorinus, will lead a force of thirty thousand picked men. Those who will serve as legates we will announce later.'

There was an intensity of gaze among the members of the consilium. Whatever they really thought of the young emperors, all the comites knew that it was on expeditions like this that serious advancement could be secured, a glittering career made.

'In advance of the main expedition, Gaius Calpurnius Piso Frugi, the governor of Syria Coele, will lead fifteen thousand men to secure first a crossing into Europe at Byzantium, then the provinces of Thrace and Achaea. Again, those who will serve as legates will be announced later.'

Macrianus the Younger looked up at the thick cedar beams supporting the high roof. 'We bow to the will of the immortal gods, put our lives in their hands. They will not fail to support us. The tyrant Gallienus has rescinded the persecution of the Christians. The natural, powerful gods of Rome will not suffer those who deny them to go unpunished. Jupiter Optimus Maximus, all the gods, they will hold their hands over us.'

The young Augustus relapsed into the immobility and distant stare the Romans thought fitting in an emperor. Ballista wondered how much of it was well-schooled play-acting. Was he just mouthing the words, or did the younger Macrianus share his father's terrible certainty about the divine?

Out of the corner of his eye, Ballista saw a movement. It was the walking stick of Macrianus the Elder. Its silver top, with its bust of Alexander the Great, nudged towards Quietus.

As the young emperor prepared to speak, Ballista studied him. Quietus had the features of his family. Since his accession, Macrianus the Younger had acquired a simulacrum of maturity, but Quietus had not. The pouchy eyes, receding chin, the long, straight nose… all still carried the look of a spoilt, petulant and vindictive youth.

'Comites -' Quietus began in too high a register. He coughed, looked annoyed and started again. 'Comites, when our brother and father march, we will remain in Antioch, governing the east. The Praetorian Prefects, Maeonius Astyanax and Ballista, will advise us. As Piso Frugi heads the advance to the west, his province of Syria Coele will be governed by our most loyal subject Fabius Labeo.'

The boy paused for the elderly ex-consul to express his thanks.

'As we have heard from Maeonius Astyanax,' Quietus continued, 'in general, the east stands secure. But the duties of a ruler never end. The governor of Palestine, Achaeus, informs us that his province, always an unruly one, is suffering a plague of bandits. These evil-doers must be eradicated. To this end, we order our Praetorian Prefect Ballista, even in the depths of winter, to descend on them with fire and sword. He will take a thousand men, infantry and cavalry, and he will put an end to these brigands. He will rout them out – and their sons too, that they may not grow up to follow the example of their fathers. Not one will be left alive.' Quietus looked at Ballista. He seemed to be relishing in advance the suffering of innocents.

'We will do what is ordered, and at every command we will be ready,' Ballista intoned. Allfather, he hated this.

A half-smile played across Quietus's face. 'To put at rest the mind of the Vir Ementissimus, given the unfortunate events when he was last away, we are happy to extend our protection to his family. Ballista's wife and sons will reside with us, here in the palace.'

Ballista had no choice. As he expressed his thanks, he felt a deep foreboding. Allfather, let Julia and his boys be all right while he was away, let nothing bad happen to them.

Quietus could not prevent a high-pitched giggle.

One day, you little bastard, thought Ballista, maybe not soon, but one day. Ballista had marched his men down from Antioch to Caesarea Maritima in the province of Syria Palestina. It had been fine. On their left, the mountains of Lebanon, in the bright mornings their cedars often shrouded in fine mists. To their right, red sandhills and, beyond them, the sea, flashing violet, blue, black in the winter sun. They had passed through the famous cities of ancient Phoenicia: Tripolis, Berytus, Sidon and Tyre. They had negotiated the outcrop known as the Ladder of Tyre, where the road overhung precipices of naked white rock. Once they had rounded Mount Carmel, the coast road had been covered in a drift of millions of shells. White, brown, purple, they cracked and rattled under the horses' hooves and the boots of the men.

Throughout the journey, the noise of the sea was in their ears. The surf was magnificent, rolling in great billows, breaking then forming again. The weather had held fair, but it was obvious the shore was a cruel one. Ballista counted eight ships wrecked; some still almost intact, others little more than discoloured lines in the sand. Maximus, of course, counted fourteen. The new secretary Hippothous claimed to have seen no fewer than twenty.

Caesarea Maritima, the city built by King Herod, was a fine place. Ballista had been busy there: endless sessions with the governor Achaeus, his legates – including the stony-faced senator Astyrius – and other officers to plan operations to scour the land of bandits. It had soon become clear why Achaeus needed aid. Several districts were overrun: Samaria, Galilee, Judea itself. Detachments to the emperors' field armies had cut the governor's command to the bone. There were no more than two thousand men with the eagle of Legio X Fretensis at Aelia Capitolina, and just a thousand with that of Legio VI Ferrata at Caporcotani. The number of auxiliary units had been slashed. There were only two alae of cavalry and six cohorts of infantry: nominally four thousand men, but these likewise were under strength. They were spread thin throughout the province.

The troops of Ballista would act as a strike column in Galilee. It was a large area for their very limited force. The northerner had led down a vexillatio of five hundred drawn from Legio III Gallica commanded by an amiable centurion called Lerus, and a wing of Dalmatian cavalry of the same number under the big red-headed prefect Rutilus.

The mission was important. It was no fool's errand. Yet Ballista was unhappy to have left Julia and his sons behind in the palace. He prayed they would be all right. He did not trust Quietus.

His worries aside, the stay at Caesarea would have been pleasant – certainly the palace on the headland by the sea was more than comfortable, and Ballista usually enjoyed throwing himself into military planning – but for the personality of the governor. Not only was Achaeus a close amicus of Macrianus the Elder, he was also a bore and a bigot. A Praetorian Prefect Ballista may be, but the rules of society demanded that he frequently accept the governor's hospitality and, at least outwardly, give some small sign of enjoyment. And then he had to campaign with him. Ballista had reclined through meal after meal as Achaeus dilated on his favourite topic: the iniquities of the Jews he ruled.

'I tell you, they are far more pernicious even than the disgusting Christians. Those superstitious fools, when they are not shouting "I am a Christian and I want to die," they at least keep repeating, like the cawing of so many trained crows, "Thou shalt not kill; Thou shalt not kill." If the god of the Jews had mentioned the latter to them, the circumcised ones were not listening. Three massive uprisings under the emperors Nero, Trajan and Hadrian. Continuous trouble the rest of the time. A nightmare to govern, like living with a stepmother. The Jews hate mankind. As the saying goes, they would not show a non-Jew the way or give him a drink of water. More likely, they would cut his throat. They're always fighting. When they're not persecuting good citizens who worship the natural gods or attacking the Christians and the Samaritans, they turn on each other. Do you know, I asked the emperor Valerian why we did not deal with them once and for all? Do you know what he said? "They may be mad, but unlike the Christians, their madness is ancestral." Addled old fool, thank the gods he has gone. When I mentioned it to the father of the noble emperors set over us now, may the gods preserve them, I got far more sense. "One enemy at a time," Macrianus said. "The Christians first, then the Jews."'

Every evening, when the eating was done, when Ballista could have been enjoying his wine while listening to the roar of the surf on the harbour walls, the boom of more distant breakers, Achaeus told stories that only a child or a Greek geographer could believe: 'Everyone knows what they used to do before the divine Titus destroyed their temple. They would catch a Greek, hold him prisoner, fatten him up, then kill and eat him. They are probably still at it, up in the hills of Galilee under their so-called patriarchs.'

Red-faced, Achaeus would warm to his topic: 'Do you know why they will not eat pigs? No, I will tell you. Because they worship them! Do you know they will not eat hares either? Why? Because hares look like miniature donkeys, and they worship donkeys too!' On and on the calumnies rolled, by turns vile and ludicrous, drowning out the clean roar of the sea.

After fifteen days, Ballista had been glad to get away from the odious governor. But he wished the weather had not finally broken. It had been merely overcast when they set out from Caesarea three days earlier. The first night had been spent in the echoing near-emptiness of the legionary fortress of Legio VI at Caporcotani, the second in the town of Sepphoris. They had waited there a day. At dusk the force had divided and marched out as the rain began to fall. Their target was a village called Arbela which was overrun with bandits. It was to be a pincer attack at first light. The legionaries from III Gallica under Lerus were to march to the Sea of Tiberias and approach the village from the east. Ballista and Rutilus, with the Dalmatian troopers, were to come in from the west. Ballista suspected that Lerus and his men had drawn the better lot. It was as well the cavalrymen had left their mounts at Sepphoris: Ballista was glad Pale Horse was safe in a stable. The hill path was hard going for men on foot. And it was cold, very cold.

Winter had come with a vengeance. In the dark, the wind tore down the rocky Galilean hills. It tugged at the olive trees and dwarf oaks. It gusted rain. The weather would choose tonight to turn, Ballista thought sourly.

The wind had veered straight into their faces. The men marched hunched over, heads down and turned away, trying to find some shelter from the blasts.

Not long after midnight, the rain had stopped. Soon after, the first watch fires glittered on the hills. The bandits of Arbela knew they were coming. Ballista was unsurprised. As far as he had gathered, the Jews had no love of the Roman occupiers. Caesarea had a large Jewish population, and Sepphoris was a Jewish town. It was no wonder the brigands had been forewarned. One man's bandit was another's freedom fighter. Ballista set his shoulders. There was nothing to be done but press on.

Ballista trudged behind the native guides. The strap of the shield slung over his back dug painfully into his left shoulder. The sword belt over his right was only a little less painful. He did nothing to shift the weights. Any movement would expose part of him to the wind. Allfather, it was cold.

'Dominus.' Maximus's voice broke into Ballista's discomfort. 'I cannot see Calgacus. The old bastard must have dropped back.'

Reluctantly, Ballista looked around. It was a dark night. He could not see far, but Maximus was right. Raising his voice over the keening wind, Ballista told Rutilus to take command and keep going; the standard bearer Gratius and secretary Hippothous were to carry on with the troops.

Ballista and Maximus stepped off the path. Slowly the soldiers passed, like mourners in a procession, only quieter.

Calgacus was near the rear of the column. He was staggering slightly. Ballista and Maximus fell in on either side. The Caledonian did not appear to notice.

'Calgacus,' Ballista called.

The old man did not respond. Swaying slightly, he carried on walking.

Calgacus stumbled, almost fell. They caught his arms.

'I'm fine. Leave me alone.' Calgacus's speech was slurred.

'Halt – that is an order.'

Calgacus stopped. He started to fall. Maximus grabbed him.

'Halt the column,' Ballista shouted to the nearest trooper. 'Pass the order up the line.'

The backs of the nearest troops stopped moving. They stood bent over like beasts of burden.

Ballista and Maximus manoeuvred Calgacus to the side of the track, lowered him to lean against the trunk of a tree.

'I am fine. Get the fuck off me.' Calgacus's words were thick, like those of a drunk. He shut his eyes and groaned. Now they had stopped, Ballista could feel the muscles in his own legs twitching, trying to cramp.

'Dominus.' It was a Dalmatian trooper. 'Dominus, the rest of them, they have gone.'

Ballista peered into the night. His eyes streamed from the wind. The soldier was right. Six troopers and an empty path. Fuck. Someone had not heard the command over the noise of the marching and the wind. Or someone had been too far sunk in cold misery to understand what had been said. Fuck.

Ballista stood, wondering what to do. The wind plucked at his cloak. There were four watch fires visible on higher ground around them. Nine men left behind, one of them incapacitated. They were cut off, surrounded.

Ballista crouched down, gazed into Calgacus's face. It was very pale in the darkness. The old man was shivering violently. That was good – he was not yet in the last stages of dying from exposure.

'How goes it, old man?'

Calgacus smiled. 'Fine.' Drowsily, he shut his eyes.

Ballista slapped his face. 'Wake up, you old bastard.'

Calgacus opened his eyes. They were not properly focused.

Ballista hugged the old man close. He spoke fiercely into his ear. 'Go to sleep and you will die. And you are not going to die on me.'

Calgacus nodded.

Ballista got to his feet. The nearest fire was not far. There was no other way.

'You four' – Ballista pointed – 'huddle round him, give him your body warmth. You two, keep watch each way down the track, keep moving, try and keep warm. Maximus and I will get fire.'

They got ready. At Maximus's suggestion, they left their shields. A brigand may have a shield, but not a big circular army one. Now their silhouettes would not give them away.

'You remember Pigeon Island?' Maximus asked. It was getting on for two years ago, but to Ballista it seemed half a lifetime ago. On a little island south of Ephesus, the two of them had carried out a similar raid to snatch fire from a Borani watch camp in order to burn the barbarians' longboat. 'Sure, but this will be fun too.'

'You are a very strange man,' said Ballista.

They set off up the hill. Initially, Ballista led them away from the nearest fire. They needed to come up on it from downwind. There was no necessity for extreme caution. The howling wind should cover the noise of their approach, but they moved carefully anyway, a few steps apart, as if patrolling. The concentration needed took their minds off the cold.

Time largely loses meaning when you are climbing a dark, windswept hill with part of your mind on what will happen at the end of the climb. The wind sighed through the trees, branches creaked, stones turned under foot and mud tugged at their boots. It started raining again.

When they grew close, they slowed. About thirty paces away, they stopped behind a dwarf oak. Wiping the rain out of their eyes, they peered around the gnarled, slick trunk. Now the cold returned. Maximus passed Ballista some air-dried meat. He chewed it without thinking; it prevented his teeth chattering.

They could see two guards. They threw elongated, shifting shadows as they paced about, stamping their feet. There were other, indistinct, shapes huddled in blankets by the fire.

Ballista would have liked to observe longer, but there was no time. He touched Maximus's shoulder. They clasped hands.

Stepping out from behind the oak, they walked forward. No point in running, risking a fall, until they were seen.

The man Ballista was after was unobservant. The northerner ran the last few paces anyway. His sword swung. The man started to turn. The blade caught him on the jawline. He screamed wordlessly. Retrieving the weapon, Ballista finished him with a powerful blow to the back of the neck.

Another man was rising from his blanket. Three quick steps, two chopping blows, and he sank down again. Ballista moved on. The next one had risen to his feet and was struggling to free his weapon. Ballista drove the steel into his stomach.

Turning, scanning for threats, all Ballista saw was Maximus finishing off a man on the ground. Seven dead. All over in a matter of moments.

A branch cracked up the hill. Dark shapes were moving through the trees; five, six, maybe more. Fuck. Surprise was on their side. Ballista and Maximus moved a little apart.

The first one tore downhill at Ballista, sword out in front. At the last moment, Ballista brought his blade down and across, driving his opponent's weapon out to the right. Ballista dropped his left shoulder, braced himself. The man crashed into him. Using the impact, Ballista shrugged him off to the right.

Straightening, Ballista parried the next one's sword to the left. He brought his elbow hard up into the man's nose. As the man staggered back, Ballista cracked the pommel of his sword down into his face. He fell back, howling.

A quick step to the right, and Ballista arced his blade down at the first opponent, now scrambling to his feet. It bit into something. No time to check. Ballista spun round. A third bandit lunged. Ballista leapt backwards, arms up, arching his body. Sparks flashed as the blade scraped along the mail covering Ballista's chest. He and his opponent were wedged together, face to face.

They struggled, feet slipping, too close to use their weapons. Ballista was aware of the second attacker getting up from the ground. The man Ballista was grappling with tried to bite his nose. Ballista twisted away. The teeth tore at his cheek. The blood felt hot. The fingers of the man's left hand were clawing for Ballista's eyes. The northerner slammed the heel of his right boot down on the man's instep. His grip slackened. Ballista broke free, with his left hand drew the dagger from his right hip, stabbed it hard into the man's crotch.

The last attacker on his feet began to back away. Ballista moved carefully towards him. The man turned and ran. Ballista was after him. The man lost his footing in the mud. He sprawled forward. Ballista was on him, driving the point of his blade down into his back.

Ballista got up quickly. No sound of steel on steel. No fighting. Some low sobbing and a high-pitched wailing. A few paces off, a dark figure moved, a bit shorter than Ballista. The blur of its sword glinted in the firelight as it chopped down again and again. Of course Maximus was fine.

Ballista walked back to his two injured opponents down on the ground. Bracing his boots in the mud, he killed both of them. There was no point in keeping them alive. He did not speak their language, could not interrogate them. He was not in the mood to try.

Ballista retrieved his dagger from the dead man's crotch. He wiped its blade and that of his sword, sheathed them.

'Sure, but you cannot say that was not fun.' Maximus was beaming.

'You really are a heartless, violent bastard.' But Ballista could feel the post-battle euphoria seeping through him. He was alive, unhurt. He had done well, not let himself down, nor anyone else. Yes, in a horrible way, Maximus was right: Ballista had enjoyed it.

'Do you think there will be any more of them along?' asked Maximus.

'No idea. But it would be a bugger trying to light a fire down on that track on a night like this. Go and get the troopers to carry the miserable old bastard up here.'

Maximus turned to go.

'And hoot like an owl when you come back, to make sure I do not kill you.'

'As if you could.'

'As if I could,' said Ballista. It rained on and off all night, but no more brigands appeared out of the darkness. Ballista and his men built up the fire. Sheltering him with their cloaks, they changed Calgacus out of his wet things, massaged him with some oil they had heated, put him in the driest clothes that could be found in the soldiers' packs. They gave him something hot to drink and drank some themselves. The old Caledonian complained a lot – an impressive range of obscenities in a variety of languages. He would be all right.

The morning came up fine; there were just the retreating, tattered remnants of the storm clouds. They went back down to the track and followed it without incident up to Arbela. The village was spectacularly sited on the edge of a cliff. Both units of troops were waiting.

Rutilus made his report. There had been a half-hearted attack just before his column had reached the village. Two troopers had been wounded, neither seriously. Only one dead bandit had been left behind. They had stormed into Arbela at first light. It was deserted. Miraculously, after a lengthy night march, Lerus's legionaries had arrived within half an hour.

'The mission was compromised from the start,' said Ballista. 'No wonder they had all disappeared.'

Rutilus smiled. 'Some of them have not gone very far.'

The tall prefect led Ballista to the edge of the cliff. The view was incredible. Down to the right, the northern end of Lake Tiberias was spread out, shining blue under the winter sun. Straight ahead, far away in the distance, was the snow-capped summit of Mount Hermon. It must have been fifty miles or more away.

On top of the cliff, the wind buffeted them. Ballista looked down. There was a sheer drop of two, three hundred feet of jagged grey rock. Below that, a gentler incline of about the same height. The lower slope had some green cover. A few pale-grey paths graded up it to the foot of the rockface. The tiny figures of Roman soldiers moved down at the bottom of it.

'There are caves in the cliff,' said Rutilus. 'Some of the brigands have taken refuge in them. We cannot get at them from below. The paths are too steep and narrow. A child could tip stones down and sweep our men off.'

Ballista looked at the cliff, the slope, the valley below, and the opposite cliffs. The latter were too far away – nothing of use there. He turned and regarded the clifftop: the few bent trees, the village of well-built houses, a synagogue at one end.

'We could starve them out,' suggested Rutilus. 'Although,' he added, 'we do not know how well they are provisioned.'

'No,' said Ballista. 'Sitting here doing nothing seems weak. If we show weakness, every bandit in Galilee will be on us.'

They stood, gazing down at the pitted rocks, the dry bits of vegetation that offered no safe handholds. Suddenly Ballista laughed. Rutilus looked inquiringly at him.

'The village – tear it down, have the men collect all the timber, anything of a decent length. Have you sent for the horses? Good. When they come, send men down to the town of Tiberias on the lake. It is a port of sorts. There must be ropes and chains there. Collect all of them. And gearing oil and pitch, get a lot of pitch. Also send men back to Caporcotani. Collect bows from the arsenal in the legionary fortress. Not many, about forty or fifty. And a mobile forge – Legio VI should have more than one.'

'We will do what is ordered, and at every command we will be ready.'

'We are going to build two or three cranes up here on the top of the cliff. We will lower bowmen down in cages. They will burn the brigands out with fire arrows.'

Now Rutilus laughed. 'Dominus, that is brilliant.'

'Yes, it is. Unfortunately, it is not my idea. A client king of Rome had trouble with bandits – it must have been here or nearby. Josephus in his History of the Jewish War tells us what he did. You see, a man who reads history is often prepared.' It took eight days for the preparations to be complete. In the end, available materials dictated that only one crane was built. None of the soldiers was in a hurry to volunteer – it was amazing how few of them admitted any skill with a bow – until Ballista announced that the men in the cage would get a cash incentive comparable to that given to those in a storming party at a siege.

Ballista had never suffered from a fear of heights. That was just as well. The cage rocked horribly as it was swung out over the void. The rockwall looked sharp and unforgiving. The valley was a long way down.

Not a sound came from the well-oiled winches, but inevitably the timber creaked and the ropes seemed to hum with tension as the cage began its jerky descent. Once, a gust of wind threatened to smash the flimsy wooden cage against the cliff face. Ballista clung grimly to the bars. The five soldiers with him cursed or prayed as the mood took them.

Ballista glanced down at the vertiginous drop. Ant-like figures were scurrying up the paths. With luck, the brigands in the caves would be too distracted by the soldiers arriving from above like a deus ex machina to interfere with the ones below.

The mouth of the first cave was a rough black oval in the pink-grey rocks. It was too dark to see far inside. Ballista half-saw movement. He ordered his men to shoot. Moving cautiously, they handed round the one guttering torch and lit the pitch-soaked rags tied around their arrowheads. A word of command and the missiles streaked away. Before the thin, oily trails of smoke had dissipated, there were screams from the cave.

'Surrender,' Ballista yelled in Greek. 'Any old men, women, children will be spared.'

There was no answer. Ballista tried again in Latin. Still no answer. He indicated for another volley. He glanced down. The ascending troops still had a very long way to climb. Looking back, he noticed a faint glow in the cave. Something in there must be alight.

A figure emerged from the depths of the cave. Ballista indicated to his archers not to shoot. The man – in middle age, smartly dressed – looked contemptuously across at the soldiers. He had a drawn sword in his hand.

'Lay down your weapon,' Ballista shouted in Greek. 'Give yourselves up. Women, children, the elderly – all will be spared.'

The man actually laughed. 'Is nowhere safe from you Romans – not even the humblest village, the most remote cave?' He spoke in educated Greek. 'Even your own writers admit that you create a desert and call it peace.'

The incongruity of it struck Ballista – he was dangling halfway down a cliff and a Jewish brigand was quoting Tacitus to him in perfect Attic Greek.

'Show yourself a man,' Ballista called. 'Give yourself up and save your loved ones.'

'I will show you I am a man.' He turned and shouted back into the cave in a language Ballista did not know – presumably Hebrew or Aramaic.

A woman came out, leading a boy, no more than ten. The man took the boy's hand. The woman fell to her knees, alternately clutching at the boy and the man's knees. Sobbing, she implored him in the language he had used.

The man spoke brusquely to her, waved her away. Reluctantly, she shuffled backwards.

The man ruffled the boy's hair. He talked tenderly to him. Then he seized the boy's chin, yanked it back. The sword flashed. It is not easy to cut someone's throat. The boy tried to wrench free. The man had to saw the blade across his neck repeatedly. Blood soaked the child, the man's arm. The boy writhed and then slumped. The man pitched the pathetic corpse out into the abyss. It fell, thumping into the cruel rocks.

Ballista and the soldiers stared in silent horror. This Jew was like no bandit they had ever encountered.

Once more the man shouted into the cave. He was answered by wailing. He shouted again, angrily.

The fire in the cave must have spread. This time, as the woman led out another, younger child, they were backlit by a hellish orange glow.

Ballista whispered to the soldier next to him: 'Shoot him.'

The man tried to force his wife away. She clung on. He tore her hands from the child. Still gripping her wrists, he swung her around, her sandals off the ground. One push and she was gone. The scream was cut off when she first hit the cliff.

Next to Ballista, the archer waited to get a clear shot.

The little boy – too young to understand – wobbled on immature legs. Allfather, he could only be two – the same age as Dernhelm. The father reached for him.

Intent on his murderous defiance, the man did not see the arrow coming. As he straightened up, it hit him square in the chest. He was pitched backwards, hands clutching at the fletching protruding from his body.

Ballista yelled up to the crew of the crane, some fifty foot above his head. 'Take us in!'

For long moments nothing happened. The child teetered, terribly near the drop. The fire burned in the cave. The cage jerked as the pulleys bit. It swung towards the cave mouth.

Ballista climbed up on the rail. He waited, judging the moment. He did not look down. A couple of paces away, he jumped.

The wind was knocked out of Ballista as his stomach hit the lip of the cave. His weight, that of his armour, began to pull him backwards. His fingers tore at the rocky ground, feet scrabbling a shower of stones. The child shied away from him – the little feet inches from oblivion.

Ballista hauled himself up, lunged across the cave mouth, grabbed the boy around the waist.

The wooden cage bumped against the rockface. The soldiers leapt out. Drawing their swords, they went into the cave.

'Only the men,' Ballista shouted. 'Only the men.' He hugged the wailing child.

Julia was standing by a window in the imperial palace on the island at Antioch. It was nearing the end of a gentle spring night. The stars were not yet paling, but soon the eastern sky would start to lighten.

It was the night before the ides of May. It should have been more than warm enough to leave the windows open, yet there was a chill to the breeze blowing down the Orontes. Julia could feel it drying the sweat on her body.

She was tired. She took a last look around. The moonlight rendered the room almost two-dimensional, tried to make it unreal. But she knew it would always have a terrible reality in her memories. She would never be able to forget this night before the ides of May.

As quietly as she could, Julia crossed the room and slipped through the door. Outside, expensive lamps in niches gave a soft light. She ignored an imperial a Cubiculo. She blushed as she felt the chamberlain's eyes on her, sensed his prurient interest. Some way down the corridor, beyond the guards, Anthia, her maid, was asleep on a divan.

Pulling her veil over her head, trying to walk as if it was a normal night, as if nothing was out of the ordinary, Julia passed the Praetorian guards. She could feel their eyes on her too. Had the sounds travelled this far?

Anthia woke at once. 'Is everything all right?'

How could anything be all right after what had happened? 'Yes,' she said. 'It is time to go.'

The imperial palace was a labyrinth of passages. At this hour of the morning, they were largely deserted. Having been forced to live there with her familia for months, Julia knew the way without thinking. The two women walked in silence.

Could she have stopped it? Could anything have stopped it? Myths were full of gods and goddesses intervening at the last moment to save girls and nymphs from other deities. A few miles from here stood the very laurel tree that Daphne had been transformed into a moment before Apollo would have had her. But the gods do not exist. Anyway, even in the myths, they seemed only to save young virgins.

There were stories that did not involve any gods. Greek girls drowned themselves in rivers, stern Roman patriarchs cut down their own daughters, but neither situation applied to her. Her father was dead, and she had been trapped in a heavily guarded first-floor dining room with adjoining bedroom. And the threat had been to her children. Dead, she could not have protected them.

She had tried to talk to him, to reason with him. Quietus's father needed her husband to command their forces; Quietus himself needed Ballista to oversee the troops in the east, for his own safety. The odious young man, his hands pawing, had shrugged her arguments aside. His father would triumph in the west. The imperium reunited, any need for Ballista was gone. She should think of her future, of her children's future. She and they would need a protector when Ballista was dead. They needed protection now – an emperor's will was law.

Trying to fend off his hands, she had persevered. What if Macrianus did not win? The advance expedition to the west under Piso had gone completely wrong. First Piso had withdrawn to Thessaly, where he had declared himself emperor, then he had been killed by Valens, the governor of Achaea, who was loyal to Gallienus. What if Macrianus did not come back?

Quietus had just giggled. There was, he had said, a sculpture in Cilicia set up by the great Assyrian king Sardanapallus. It represented the fingers of the right hand snapping. The inscription on it read: 'Eat, drink, fuck; everything else is not worth this.'

For a moment Quietus had looked serious. Yes, if his father failed, it would be the end – the end of all things. Yet just as old Sardanapallus had taught how to live, so he showed how to die. He would gather all the things that had given him pleasure. The silks and jewels, the spices and inlaid furniture, he would have them heaped up. The women he had enjoyed and the horses he had ridden would be sacrificed on the pyre. Then, from a high place, he would throw himself into the conflagration.

Julia saw that Quietus was not joking. She was sure he was mad.

As he pulled her off the dining couch and led her to the room next door, he recited poetry: 'For I too am dust, though I have reigned over great Nineveh. Mine are all the food that I have eaten, and my wild indulgences and the sex that I have enjoyed; but those numerous blessings have been left behind.'

Should she have fought him? She had pushed him away from her face when he tried to force her to do something no decent Roman matron should do. He had slapped her hard and asked in a hiss if she would like him to order some Praetorians to come in and hold her down. There was a full contubernium of ten men on duty tonight; he was sure they would all like to take turns with her when he had finished. She had done what he wanted. Her reluctance seemed to increase Quietus's pleasure in the act.

She had asked him to put out the lamps. Quietus had laughed: even the most respectable Roman matron lets the lights burn so her husband can admire her on their first night. Surely she would not deny her emperor, her dominus, the pleasure of gazing at the shrine where he was worshipping? A shrine defiled by a barbarian, but now being reconquered for Rome.

Julia tried to push the physical from her mind. What should she do now? Of course, early Rome provided a stern exemplum – did it not always? Raped by one of the sons of Tarquinius Superbus, the noble Lucretia had killed herslf. Why? She herself had said that only her body was defiled, her soul was not guilty. Her husband and her father had agreed; guilt fell not on the victim but on the rapist; the mind sins, not the body. It had made no difference. Lucretia was her own harshest judge. She absolved herself from guilt, but not from punishment. In the future, no unchaste woman would live, thanks to the precedent of Lucretia.

Julia had not tried to kill herself before being raped, and she had no intention of following the precedent of Lucretia now. Julia had submitted to protect her children. She was not going to stop protecting them now. She would just have to carry on as if nothing had happened.

Could she keep it quiet? Rhea, raped by a river-god, had killed herself in case her blush betrayed her to the mob as an adulteress. Ridiculous, thought Julia. It showed the weakness of Rhea, that she let her body betray her by blushing. And it indicated her stupidity – first to equate a woman who had been raped with an adulteress, and then to care what the unwashed plebs thought.

But what about Ballista? He would go mad – literally, mad – if he found out. Was he likely to? The slaves and freedmen of the imperial bedchamber would know. Ballista was highly unlikely to be talking to them. The story might spread amongst the Praetorians, if the two in the corridor had recognized her or one of the imperial servants named her in their hearing. That was far more dangerous; Ballista was one of their commanders. There was nothing she could do about that.

A sickening thought hit Julia. After abducting and raping their wives, the emperor Caligula used to enjoy an over-dinner discussion of their performance with their husbands. Might Quietus gloat in the same way? At first, before he had resorted to threats, when it was still oily seduction, he had tried to encourage her by saying that no one need know – it would be their secret. How much faith could be put in that?

When summoned to the dinner party, Julia had taken only one maid with her. Anthia was loyal. She would not talk. They could slip back into their own apartment. The rest of her household need not know.

Another sickening thought broke over Julia like a wave. Was she in some way to blame? Why had she taken only one maid? Had she been expecting it? Had she been already limiting the witnesses, or almost inciting the rape by her lack of care?

Of course it was not her own fault. She dismissed the disgusting idea with the ingrained self-control of her senatorial background. She had feared what might happen from the moment she had been ordered to dwell in the imperial palace while her husband was away. She had not shared her fears with Ballista. His barbarian nature would have driven him to spontaneous and disastrous actions. Daughters of the senatorial nobility of Rome did not give way to emotions; the icy self-control did not slip.

And when at last it was over, when Quietus put out the lamps and straight away fell asleep, why had she merely got dressed in the dark and left? Quietus had been lying on his back, naked, exhausted and defenceless. There must have been something that could have been used as a weapon somewhere in the room. He was unconscious. Why had she not tried to kill him?

Of course she knew the reason: she would have been caught and executed. The children would have lost her, possibly suffered themselves. Even as she framed the thoughts, she knew they were not the real reasons. She had been too shocked and scared to act. She had behaved exactly as a Roman man would expect a woman to behave. Unlike at the fall of Antioch, she had been weak, timorous, irresolute. Her behaviour disgusted her. Her disgust encompassed the world. This world created by men, this imperium, was an unfair world.

They were now at the side door, the one that led straight to Julia's private rooms. Anthia was waiting, clearly expecting her to say something. No words came. At last Julia spoke: 'I am no Luctretia. I must protect my children. Tell no one. This must be our secret.' The waves, driven by the continual south-westerly, crashed and boomed against the harbour defences of Sebaste, the name given to the port area of Caesarea Maritima. Calgacus had walked the southern breakwater, followed it when it dog-legged to the north, all the way to the big lighthouse at the end. High on the battlements, the late-spring sun was warm on his shoulders. Calgacus remembered the bitter cold of that night back in the winter when he had nearly died on a Galilean hillside. Gods, but it was good to be warm and alive; a free man with time on his hands. He looked around.

To his left, out to sea, the lines of white-topped water rolled in relentlessly. One after another, they thundered against the rocks at the foot of the mole. The spray flew high, jewelled in the sunshine. They were powerful, these waves, but there was no malice in them. They might kill you, but only in an absence of mind. Unlike a winter storm, they would mean nothing by it.

To the Caledonian's right, the port was busy. Out in the road-stead, three big merchantmen were being taken in tow by open rowing boats. The first of them was already being drawn into the narrow, north-facing harbour mouth between the pharos where Calgacus stood and the harbour master's house at the tip of the other breakwater. Inside, another six or seven large roundships were tied to the several jetties. There were many more small coasting vessels or local fishing boats at rest or moving. Away in the innermost basin, an imperial trireme was moored.

It was good the port was busy. According to local reckoning, the sailing season began eleven days before the ides of March, the day marked by the two festivals of the birthday of the Tyche of Caesarea and the coming to the water of the goddess Isis to bless the sailors. That day had long passed. Now, just ten days before the kalends of June, even the most cautious would have to admit that the time when the seas could be sailed with some safety was fast approaching. It was good the port was busy, for, with the imperium divided into three, attacked on every frontier, and with civil war between the forces of Gallienus and those of Macrianus being fought out in the Balkans, nothing was certain.

Calgacus supposed he should be doing something, but there was no great urgency. Ballista, Maximus and the troops were away on their final mission in Syria Palestina. This task had no particular target, being no more than an armed march through Galilee as a show of strength. No opposition was expected. It was not so much that all the previous missions throughout the winter and spring, and the many they had killed, had destroyed the opposition as the fact the locals knew they were leaving. Why attack a dangerous enemy who is about to withdraw anyway?

The whole thing seemed futile to Calgacus. The Jews were united in their hostility to Roman rule. The Jewish brigands or rebels – how was one to tell them apart? – if they did not want to fight, they just merged back into the population. It was quite clear that no Jewish patriarch would hand over to the Romans even the most bloodstained murderer. The whole thing was a complete kick of the arse to nothing.

In two or three days, the expedition would return. Calgacus and the new secretary Hippothous had been left behind to put their affairs in Caesarea in order. Apart from a couple of minor things, they had done so. As soon as he was back, Ballista wanted to be free to march north, to Antioch and his family. Calgacus knew Ballista was worried about his familia living in the imperial palace.

Calgacus wondered what kind of reception they could look forward to in general. Macrianus father and son were in the west. Quietus, the only member of the imperial house in Antioch, particularly hated Ballista. Throughout his campaign in Galilee, Ballista had continuously ignored one detail of his imperial mandata. He had always spared the male children – only selling them into slavery, rather than killing them.

Soft-hearted, Ballista had always been soft-hearted, ever since he was a child, thought Calgacus. Still, it was part of his humanitas. That hard-to-define quality – it was part of what made Calgacus love him and, very strangely, it seemed to be part of what made rough, violent men follow him.

Calgacus was pleased that Ballista had taken the small Jewish boy he had rescued from the cave at Arbela into his household. Simon-bar-Joshua, he was called. Simon was a good-natured boy. Ballista had bought a young Jewess to look after him. Calgacus was pleased with that too. There was something about the way Rebecca moved, something about the look in her eye, that made you think what she would do for a man she liked. Calgacus felt a familiar stirring. But it was not at all the right moment. It was not yet noon. Almost all the brothels would still be shut. The one he liked, out by the north harbour, very reasonably priced, would certainly not be open.

To break his run of thoughts, Calgacus looked around, taking in the whole city. Caesarea Maritima: the dream of the old Jewish king Herod, the one they called the Great. Ballista had told Calgacus about Herod. A right murderous bastard he had been. Killed his relatives at the drop of a handkerchief. Put several of his sons to the sword at the merest whisper of suspicion. But he had been a political survivor. Having left it almost too late to abandon Mark Antony, he had spent the rest of his life cultivating the favour of his conqueror, the first emperor Augustus. Herod had called this new town Caesarea. Its port district was Sebaste, the Greek for 'Augustus'. The lighthouse above Calgacus's head was named after one of Augustus's stepsons, Drusus. Out beyond the harbour mouth, on two huge concrete bases rising from the seabed, six fine columns supported larger-than-life statues of Augustus and five of his close family. Inland, dominating the town and the harbour on its enormous manmade podium, was Herod's temple to the goddess Roma and the god Augustus. Its red-tiled roof and white columns were visible miles out to sea: no one could miss that.

All those ostentatious proofs of loyalty had kept Herod on his throne. But they had not shielded the Jewish client king from the sharp tongue of the first Roman emperor: 'I would rather be Herod's pig than his son.'

Calgacus decided to walk back along the quayside. Sometimes it was pleasant to walk unarmed through a peaceful crowd. It made a change, gave a teasing glimpse of how life might be different. Calgacus had no weapons on him, except the small knife at his belt – and, of course, the one always hidden in his right boot. He pulled his broad-brimmed travelling hat down on his head to keep off the sun. He whistled, tuneless but cheerful.

It was quite busy down on the waterfront. Bales, barrels, sacks and amphorae were dotted about as stevedores loaded produce from inland farms and unloaded more exotic goods from further afield. As you walked, you had to keep an eye out for the dockers in their leather harnesses hauling vessels into the right berths by sheer physical strength. Here and there at the back of the quay stood a few girls. They were of an age, not all that attractive. It was the cheaper end of the market; they were waiting for sailors for whom the voyage had been long. Such urgent needs would be taken care of standing in the inadequate privacy of one of the empty warehouses. All in all, there was more than enough to keep the telones busy. Whores paid taxes like merchants and everyone else.

It was the empty warehouses that got Calgacus thinking. Some were boarded up because they were clearly unsafe. In places, the whole edifice of the breakwater had shifted, tilting outwards, cracking the quayside, weakening the roofs and walls of the buildings. In other places, the warehouses had been shut because the berths in front of them had silted up so much that big seagoing ships could not tie up there. But others had no such physical reasons to be closed. Only a fall in trade could account for it. When you looked, there were many more mooring places than there were boats.

As he strolled along, Calgacus found himself smiling. If Ballista were here, the boy would be busy calculating the best way to repair the breakwater, dredge the harbour, how much it would all cost. Calgacus, on the other hand, did not give a fuck. He liked looking at ships, but the people of Caesarea Maritima were nothing to him. As far as he was concerned, they could all go to Hades; fuck them.

As he walked past the inner basin, Calgacus saw a crowd at the top of the steps to the temple of Roma and Augustus. The sun on his back and the sight of the girls on the dockside, even though they were not that good-looking, had rekindled his urge. It would be an extravagance to have a girl at midday just on a whim. He would definitely want one tonight, and to pay for two in a day was too much. For distraction, he climbed the steps to see what was happening.

A military awards ceremony was taking place. The governor Achaeus sat on a curule chair in front of the temple. He was backed by his consilium, including the miserable-faced senator Astyrius. The governor himself was beaming. Presumably, handing out awards and promotions to those who had done well in the campaign against his Jewish subjects was congenial to him.

Off to one side, smiling in the sunshine, stood a crowd of those who had already received their awards. Calgacus thought it typical, in this as in almost everything in Rome: what you got was as much determined by who you were as what you had done. In the imperium, the social order had to be seen to be maintained.

First, towards the bottom of the steps, were those of lower rank. They proudly sported different awards: phalerae, the metal discs attached to their chest armour; torques around their necks; and armillae on their wrists. Above them stood a smaller group, with decorations available to all ranks. These men wore crowns on their heads; of oak leaf if they had saved another citizen's life, of gold for other acts of conspicuous courage. At the top, nearest to the governor and the military standards, were those of the rank of centurion or higher. Most of them grasped the ornamental spears in precious metals deemed suitable awards for brave officers. Just two wore the Corona Muralis, the mural crown. Few officers were first over the wall of an enemy position; fewer still lived to receive the crown with its golden walls. Ballista has one of those, thought Calgacus.

The ceremony had moved on from awards to promotions. Calgacus leant against a column to watch. Strangely, on a cloudless spring day, the stone was wet to the touch. Drops of condensation like tears ran down the fluted shaft of the column.

The herald announced the first promotion. A vacancy having arisen in Legio X Fretensis, according to the order of seniority, the optio Marcus Aurelius Marinus was to be awarded the rank of centurion. His years of distinguished service, good birth and adequate means fitted him for the duty.

A well-built, soldierly figure, Marinus stepped forward.

Up on the tribunal, Achaeus was all ready to hand over the vine-switch, symbol of the rank of centurion.

Just as Marinus came before the governor, unexpectedly, another man emerged from the ranks.

'Dominus,' he called up the steps. Everyone was silent at this interruption.

'By old-established laws, Marinus is debarred from holding rank in the Roman army. He is a Christian. He will not sacrifice to the emperors. By order of seniority, the post of centurion belongs to me.'

For a moment, Achaeus looked bewildered, then he laughed. 'This is not Saturnalia, soldier. Not a time for joking.'

Calgacus noticed that Marinus was standing stock-still.

'Dominus, I am not joking,' the soldier persisted. 'Marinus is a Christian. He joined the disgusting sect years ago. Ask him yourself.'

Still half-smiling, wishing to brush this off as a piece of ill-timed foolery, Achaeus turned to Marinus. There was something about the unnatural stillness of the optio that made the governor pause.

'Is… is it true?'

Marinus's jaw started working. He seemed to be reciting something under his breath. He drew a big, slightly ragged breath.

'I am a Christian.'

There was a collective gasp from the audience. A buzz of conversation flew up.

'Silence!' The herald had to bellow. 'Silence!'

'I am a Christian,' Marinus said again, a little louder.

'Nonsense,' said Achaeus. The governor still looked puzzled. 'Do not be ridiculous. How can you be? Soldiers have to worship the standards and the imperial portraits at least once a year.'

'I have sinned. God will be my judge.'

'You have a distinguished war record. Christians do not kill.'

'I have sinned. God will be my judge.' Marinus repeated the phrase as if drugged.

Achaeus looked flustered. This scandal, treasonous and divisive, was not at all what he wanted for this ceremony.

'Marinus, you are not well. You have been through a hard campaign – the constant threat of death, terrible privations, constant bad weather. You are not in your right mind. I grant you three hours to reconsider. Sit and reflect quietly. Talk to men of sense.'

Marinus did not reply.

'You are not under arrest. No one is to harass or detain you. Return here in three hours with a better answer.'

Mechanically, Marinus saluted, turned, marched down the steps and pushed into the crowd of onlookers.

Calgacus moved after him.

Marinus had turned into the agora. It was crowded. At first Calgacus could not see him. The Caledonian did nothing precipitous, nothing that would draw attention. He just strolled on, looking this way and that – a man from out of town, travelling hat on head, taking in the sights.

An eddy in the people, and there was Marinus. The optio was with another man: older, bearded, a civilian. The newcomer was leading Marinus by the hand, talking to him, low and earnest.

Calgacus followed. They crossed the breadth of the agora. They negotiated the many stalls selling various goods. They walked by the imposing facades of the temples of Apollo and Demeter, the shrines of Isis and Serapis, the sanctuaries of Tiberius and Hadrian.

The older man led Marinus out to the north-east. The centre of town was set out in regular, Hippodamian blocks. It was easy for Calgacus to trail them inconspicuously. He thought maybe he should become a frumentarius.

After they had been walking some time, they came to the Caporcotani Gate, which led to the Great Plain and the hills of Galilee beyond. Calgacus wondered if Marinus was going to make a run for it. But as soon as they had passed under the gate, the civilian led him off to the right into the suburbs.

Outside Herod's wall, there was no street plan. Lanes and alleys twisted and turned. Calgacus had to keep closer, but he had no great problems staying both in touch and unnoticed.

Marinus and his companion came to an unremarkable door. They knocked and were admitted by a burly-looking man. Calgacus waited at the street corner. This was a poorish suburb. The buildings were mainly low, a bit shabby. The walls of the amphitheatre loomed over the area. Calgacus smiled. If he was right and this was a Christian meeting place, the authorities would not have to drag them far to meet their fate.

Calgacus walked to the door and knocked.

'Yes?' The burly man looked wary.

'I am a Christian,' said Calgacus.

The man just looked at him.

'From out of town,' added Calgagus. 'From Ephesus, just docked.'

Still the man said nothing.

'Appian, son of Aristides, who bore witness during the persecution under Valerian, told me where to find you.' It was a shot in the dark that the man would have heard of the most renowned of the Christians, whom Ballista had killed while they were in Ephesus. Calgacus had no idea if Appian was likely to have known the location of the Christians' meeting place in Caesarea. At any moment he might be needing the knife in his boot, be testing the limits of the sect's pacifism.

The man nodded, pulled back the door. 'The Lord be with you, brother. How can we help?'

'And with your spirit,' said Calgacus, pulling off his hat. 'Nothing too much, just a chance to pray in peace.'

'Come in the love of God. Please take a place at the rear. Our pious bishop Theotecnus is at the altar counselling one of our brothers in the time of his trial.'

Calgacus did as he was told. He had seen and heard Christians pray. They used different styles. But some knelt and kept their heads down. That seemed to fit the bill. From under his brows, he had a good view.

The man he now knew was the Christians' archpriest was standing in front of the altar facing the soldier. The priest leant across and drew aside Marinus's military cloak. He pointed to the sword. Turning, he picked up a book – not a papyrus roll, but a new-style codex. He placed it on the altar in front of Marinus.

'Choose,' said Theotecnus.

With no hesitation, Marinus stretched out his hand and grasped the book.

'Hold fast then,' said Theotecnus. 'Hold fast to God. May you obtain what you have chosen, inspired by him. Go in peace.'

The Christians embraced, and Marinus left.

Possibly a little too quickly afterwards, Calgacus followed. The man on the door gave him an odd look but did not try to stop him. Maybe he put it down to the visitor's prurient desire to see what happened to the martyr-to-be.

Calgacus caught sight of Marinus reentering the town at the Caporcotani Gate. The optio, looking neither left nor right, went to a house in the north of Caesarea, near where the aqueducts enter. He stayed inside for some time. Calgacus assumed it was Marinus's lodgings. He waited outside. It was no hardship. It was a nice day.

Eventually Marinus came out and set off south-west. He walked purposefully. His mind on his fate, the love of God or some such, he was easy for Calgacus to shadow. As they got near the agora, people began to point, whisper to each other and openly follow. Indeed, quite a throng trailed Marinus as he reached the steps to the temple of Roma and Augustus.

Marinus stopped. The crowd milled, taking care not to get too close to the prodigy who was both a soldier and a confessed Christian.

'Marcus Aurelius Marinus,' a herald roared. 'Your time of grace is over. Present yourself to the tribunal.'

With no outward fear, Marinus stepped forward.

You had to hand it to these Christian bastards, thought Calgacus. It was impressive. It could turn the heads of some of the plebs.

On his curule chair, the governor was not smiling now. Behind him, Astyrius and the other members of his consilium were equally stony-faced.

Calgacus would not have been alone in noting that, this time, Marinus did not salute. The Caledonian knew why. Back in the church, Marinus had made his choice: Christian, not soldier.

'Marcus Aurelius Marinus, our magnanimity has given you time to come to your senses.' Achaeus's voice was cold. 'What do you say?'

'I am a Christian.'

'So be it,' snapped Achaeus. He waved some guards forward. They seized Marinus. They stripped him of his sword belt, his cloak, his boots, anything which denoted him as a soldier.

'You will be taken to the south necropolis. You will be beheaded. No one is to give you burial. Your corpse will lie by the road for the dogs to eat.'

Marinus betrayed no emotion.

'There is no reason for delay,' Achaeus announced. 'Take him away.'

Calgacus did not need to exercise any caution in following this time. A centurion and ten legionaries, the condemned man's commilitiones, escorted Marinus. Behind them came about thirty civilians – those who especially disliked Christians or particularly enjoyed a public execution, or maybe just had nothing better to do.

Calgacus did not go all the way. He turned off to the right and entered the empty theatre by the city walls. Once he had climbed to the top of the seating, he had a good view over the rear wall.

Sure enough, the centurion halted his men just beyond the town walls, as soon as they reached the first tombs of the necropolis. With a minimum of fuss, a blindfold was put on Marinus.

By the side of the road, the Christian knelt down. He leant forward to expose the back of his neck. The blade of a sword glittered in the spring sunshine. The spatha descended. It was not a good strike. Blood everywhere, but the neck was not severed. Marinus was pitched full length. He was writhing. The executioner had to steady him with a boot on his back and a firm grip on his hair. Four, five times, the spatha chopped down until the head came away.

The soldiers left him lying by the side of the road. Without a backwards glance, they marched off into town. Some of the civilians remained standing there for a while, but soon Marinus's remains were unattended.

High up in the theatre, Calgacus made himself as comfortable as he could and settled down to wait. The night after Ballista had killed Appian in Ephesus, someone, presumably Christians, had come and stolen the body – well, seemingly, torn it apart and taken bits of it. Calgacus thought it was worth keeping an eye on what was left of Marinus.

Travellers came and went on the Ascalon road. In wagons, on donkeys, mules, horses, on foot, they passed, usually in groups, occasionally on their own. Some stopped to look at the fresh corpse, the blood already draining into the dirt, but most did not.

The waiting did not bother Calgacus – he could happily do nothing for hours on end – but he was getting very hungry. Tonight, despite the cost, he would treat himself to a really good meal before a girl – maybe that new Greek girl Chloe: she had a look in her eye, made him laugh.

The sun began to sink towards the sea. The western sky was a blaze of purples, blues and reds. The travellers had gone from the road. If nothing happened before dark, Calgacus would have to go down and creep closer.

All that was to be heard was the sound of the surf. It might have lulled Calgacus had his hunger not been so sharp. He was getting ready to move when the file of men appeared from the town.

At their head was a tall figure. From within the folds of his cloak could be seen a flash of shimmering white toga and, amazingly, a broad purple stripe. The man was a senator. It was Astyrius, and he was trailed by four servants.

They reached the dead man. At Astyrius's gesture, the servants spread a magnificent, costly robe on the ground by the remains. Astyrius reverently picked up Marinus's gory head and placed it on the robe. The servants lifted the body to join it.

The robe was carefully folded. Astyrius himself helped shoulder the burden. The illegal cortege moved off, cross-country to the east.

Well, well, thought Calgacus, who would have thought it? As he walked stiffly down the steps, he wondered if his were the only eyes that had been watching. 'Christians to the lion,' he thought.

Macrianus the Elder, Comes Sacrarum Largitionum et Praefectus Annonae, holder of maius imperium, father of the Augusti, washed the blood off his hands. A servant took away the golden bowl; another handed him a towel. They may well be on campaign, somewhere in the wilds between Thrace and Illyricum, but standards had to be maintained.

The sacrifices had told Macrianus nothing. The entrails had been hard to read, ambiguous. Surely the gods would not abandon him now? He had never yet done anything without consulting them, checking they approved. All his life had been devoted to doing their work. Not even the most malevolent could deny he had been zealous in persecuting the atheist Christians. And had he not sworn to all the natural gods – in his heart, not just with his lips – that when he had done with the followers of the crucified Jew he would turn on and eradicate the Jews themselves? Let the godless emigrate beyond the frontiers, for if they remained they would die.

Yes, Macrianus had laboured long on behalf of the Pax Deorum, the relationship between man and gods that had always sustained the imperium of the Romans. Dangerous choices had been faced, difficult decisions made. But he had been well rewarded, as his piety deserved. His rise from obscurity to riches and power, the elevation of his sons to the throne – both clearly made manifest the favour of the gods.

Macrianus knew he had done nothing but good, had done nothing wrong. True, his conscience initially had been troubled by the idea of removing Valerian. But the old emperor had been too hesitant. He had stood in the way of the work of the gods. Even so, it had been a relief to Macrianus when he received the explicit approval of Jupiter Optimus Maximus in a dream.

The opaque entrails meant nothing. The gods would not abandon Macrianus now, not in the middle of a campaign against the godless tyrant Gallienus. As soon as news of Valerian's capture had reached Gallienus, even while his aged father was being dragged around Cilicia, Gallienus had rescinded the edict against the Christians. It was said he had gone so far as to give them back their unholy meeting places and burial grounds. There was no chance the gods could favour such a man over Macrianus and his sons.

But if the signs from the heavens were mixed, they were not more so than those on earth. The advance expedition to the west led by Macrianus's old friend Piso Frugi had been a disaster. First, in the backwater of Thessaly, of all places, had come Piso's usurpation – what evil daemon could have prompted the fool to that? – then his death at the hands of Valens, Gallienus's governor of Achaea. The situation had somewhat recovered. The troops under Valens, a bunch of auxiliaries as headstrong and unreliable as all soldiers were these days, had mutinied. They had proclaimed Valens emperor. The unwanted eminence had lasted only a short time. Frumentarii sent by Macrianus's loyal Princeps Peregrinorum Censorinus had abruptly ended the ephemeral reign.

Not everything had gone wrong in the aftermath of the Pisonian debacle. Byzantium had remained loyal to the regime and it afforded the Macriani father and son and their main army a safe crossing from Asia.

As they advanced west into Europe, the mixed blessings had continued. It was a disappointment that Valentinus, the acting governor of both Moesia Superior and Inferior, had kept the provinces in the faction of Gallienus. But to balance that, the four legions stationed in the provinces of Pannonia Superior and Inferior had declared for Macrianus and Quietus. Macrianus the Elder was quite aware that this had not been prompted by love for his sons. The Pannonian legionaries were still smarting at the defeat and deaths of their candidates for the purple – Ingenuus and Regalianus – by the forces of Gallienus. They would have probably followed a trained monkey against Gallienus. Still, it gave an impression of momentum, and it was a useful addition to the expedition. When the Macriani reached Serdica, they found two large vexillationes from Legiones I and II Adiutrix had marched down to join them. There had been scenes of celebration as these newcomers mingled with smaller vexillationes from all four Pannonian legions who were already serving with the army. The four thousand newcomers roughly replaced those lost to sickness, straggling and desertion on the long march from Antioch.

The events of the day before struck Macrianus as ambiguous at best. A couple of hours' march west out of Serdica, and the enemy cavalry had appeared. It was light cavalry, and there were a lot of them; mainly Dalmatians, but also quite a few Moors, with their distinctive long, braided hair. They had surrounded the marching column, driven in the cavalry outriders. They had not killed all they could. They had ridden close, up and down the line, calling on their opponents to return to the oaths they had once sworn to the rightful emperor Gallienus. None of the marching men had gone over. Instead they had bellowed out a flow of obscenities, mainly directed at Gallienus's relationships with the barbarian girl Pippa and the philosopher Plotinus. They shouted that he defiled his mouth playing the Phoenician to the former, and all his body acting as a wife to the latter.

The military men, the Prefect of Cavalry Ragonius Clarus well to the fore, had put a positive interpretation on it all. A cavalry skirmish signified nothing. Macrianus's riders had been caught unaware, but not one soldier had left the ranks. Morale remained as high as ever.

Macrianus acknowledged he was not a military man. He always learnt what he could about any units under his command, but he was not at home in the field. Yet, even so, he was concerned at the ease with which the cavalry had given way. He half regretted leaving Ballista with Quietus – may the gods hold their hands over the boy; unlike so many, the barbarian spoke his mind. Ragonius Clarus and Censorinus had combined to allay Macrianus's apprehensions. After dark yesterday, the Princeps Peregrinorum had announced that he would go through the camp and gauge the mood of the men before going beyond the palisade and sounding out the loyalty of the enemy pickets. If anyone was considering desertion, it was likely to be the enemy. He had promised to take care, as much care as Dolon had taken in the Iliad. Macrianus had wondered at the inappositeness of the reference. Censorinus had not been seen since.

As the butchers dragged away the carcases of the sacrifices, Macrianus took up his walking stick and slowly made his way to where the imperial standards hung limp in the early morning air. His son Macrianus the Younger sat straight and true on a magnificent black charger. The boy had come on well since his elevation to the throne. He wore the purple and the radiate crown as if born to them. There was a nobility to his aquiline nose and high brow, a hint of hard service to the Res Publica in the slight bags under the eyes. If he chose occasionally to relax from the cares of empire by making small wooden toys, there had been many emperors with far more damaging pastimes.

A quiet gelding was led out. Macrianus's lame leg made riding a trial. Stoically, he let himself be helped into the saddle. Once there, he reached out and briefly gripped his son's hand. Ragonius Clarus rode up, saluted and asked permission to signal the advance.

Macrianus surveyed the scene. A broad upland valley, the road from Serdica to Naissus running through it, almost due west, a small, unnamed stream alongside the road on its left. There was a low mist over the water and, about a mile away, the enemy. A large force, but no bigger than the army with Macrianus – about thirty thousand men. It was drawn up conventionally: heavy infantry several ranks deep in the centre, bowmen behind, some light infantry with slings and javelins in front, cavalry out on the wings. The standards made a brave show all along its front. The imperial standard was not there. Gallienus had not come himself. He was further west, preoccupied with getting revenge on Postumus for the death of his son. The army was commanded by Aureolus. The red Pegasus on white banner of Gallienus's Prefect of Cavalry flew on their right wing. It was said Aureolus was supported by several leading protectores: his near-namesake and fellow Danubian Aurelian, Manu ad Ferrum; Theodotus the Egyptian; Memor the African; the siege engineer Bonitus, and the Italian Domitianus, who implausibly claimed descent from the Flavian dynasty.

The army of the Macriani was virtually a reflection of its enemy. Stationed with the thousand troopers of the Equites Singulares just behind the centre of the infantry line, Macrianus the Elder had a good view from the vantage point of his horse. Everything seemed in order. His son was looking at him. He nodded. Macrianus the Younger told Ragonius Clarus to carry on. The latter gave the command to advance.

Centurions passed the order on, bucinatores sounded their instruments, standard bearers got ready to lift.

Ragonius Clarus was shouting something over the din: 'When the mist burns off, the sun will still be low, straight in the eyes of Aureolus's men.' Macrianus was finding it hard to listen: something was wrong with the unit directly in front. It was a vexillatio from Legio XI Claudia Pia Fidelis. The detachment, originally five hundred men, now considerably less, had been sent east from its base at Durostorum in Moesia Inferior for Valerian's Persian campaign. The standard bearer in charge of the vexillum had pulled the standard from the ground with no problem, but as he began to walk forward, the shaft tangled his legs and he lost his balance. The vexillum tottered and fell to the ground. The men of Legio XI halted.

Ragonius Clarus had seen what had happened. He stopped talking.

A terrible omen, thought Macrianus.

Ragonius Clarus spurred his horse forward. He was bellowing: 'Vexillarius, pick the fucking thing up!' It was too late. Along the line, those unable to see what had caused the standard to go down drew the same conclusion: surrender. One after another, standards were lowered. Units halted. Legionaries, auxiliaries, barbarian allies put down their weapons. They stretched out their arms to the other side.

'Quick, this way.' Ragonius Clarus was tugging at the bridle of Macrianus's horse. 'The Pannonians are not surrendering. Quick, to the left.'

Macrianus looked around wildly to see that his son was safe. He was with them. They thundered across the ground.

'All is not lost,' Ragonius Clarus called over his shoulder. 'We can fall back on the camp.' 'All is not lost,' said Ragonius Clarus.

Outside, the setting sun was a huge orange ball. Long shadows stretched across the camp, played on the wall of the imperial tent. There was less than an hour to darkness.

Macrianus the Elder indicated that the Prefect of Cavalry should continue to address the much reduced consilium.

'We have nearly twelve thousand men: six thousand Pannonian legionaries, five thousand of Sampsigeramus's bowmen from Emesa, about half mounted, and a thousand Equites Singulares. A sizable and useful force.'

All true, thought Macrianus, but our opponents now have nearly fifty thousand men under arms. He did not let these calculations affect the attentive and quietly confident set of his face. The officers were shaken. Macrianus the Younger looked scared. Macrianus smiled reassuringly at his son.

'We have plenty of supplies. The camp is well fortified. We could withstand a siege,' continued Ragonius Clarus.

Which would merely delay things for a time, thought Macrianus. There is no army that will come and raise the siege. We stripped the east bare to raise this force. We have no allies waiting in the wings. And it is not even as if Gallienus were leading the besieging army himself. In that case, almost anything might have happened – a stray arrow kills the emperor, or supplies fail, plague breaks out, the men get sick of hard labour and privations, from one motive or another Gallienus's own troops strike him down… Sieges are dangerous times for emperors. But none of that could happen. Gallienus was safe in the west.

Outside, a man was shouting, near the imperial tent.

'Alternatively,' said Ragonius Clarus, 'we can break out. A night march to Serdica, then east. Byzantium is one of the best-fortified cities in the world. It would hold up Aureolus while we regroup further east.'

Other voices had joined the man shouting.

Macrianus was no soldier, but he knew a night march was a desperate venture, one that might destroy an army all unaided.

One of the Equites Singulares burst into the tent. 'Dominus!' Ignoring the young emperor, he spoke directly to the father. 'The Pannonians are mutinying. They are tearing the imperial portraits from the standards.'

Age cast aside, barely using his stick, Macrianus burst from the tent. The trooper was right: there was an ugly crowd around the standards of Legio II Adiutrix. The images of the young emperors were in the dust. Macrianus walked boldly up and halted a few paces from the mutineers. The noise dropped to a low, menacing muttering. Macrianus was pleased when, unbidden, his son came to stand at his shoulder. The boy was no coward. The show of unity might help. If ever they had needed help, it was now. Macrianus would have offered a brief prayer, but there was no time.

'Commilitiones.' Macrianus's voice carried well, betrayed no panic. 'Commilitiones, this is not how the men of Legio II Adiutrix behave. Would the men who crushed the Batavians, ventured beyond the ocean to conquer Britain, drove the Dacian king from his throne, and sacked the Parthian capital of Ctesiphon have behaved like this? The legionaries of Legio II Adiutrix do not mutiny like a bunch of eastern auxiliaries or Arab tribesmen.'

Macrianus was not sure if he was winning them over. At least they had not offered any violence so far.

'You have taken the sacramentum to my sons. We have paid you the donative we promised. My son campaigns with you. He will lead you home to your base at Aquincum in triumph. Things look difficult today, but with the gods holding their hands over us, all will be well. Commilitiones, it is time to prove yourselves true to the title of your legio: Pia fidelis.' He repeated, 'Loyal and faithful,' and stopped. He had no more words.

A centurion stepped out of the crowd. He spoke deliberately, with an accent from the northern frontier. 'You are not our commilitiones. You are not soldiers at all. It is true, you have not treated us badly. But you betrayed our brothers in the legions when you betrayed the old emperor Valerian. Treachery turns on itself. The gods move slow, but in the end their power is shown.'

The echo of Euripides in the soldier's Latin, the invocation of the gods, silenced Macrianus. No, he wanted to say, that is all wrong, you do not understand, the gods approved of what happened to Valerian, the gods want Gallienus overthrown. Until today, they have given manifest signs of their favour. But it was all too complicated. He knew then it was hopeless.

Looking around, Macrianus saw that Ragonius Clarus had gone. Macrianus and his son were alone. It was hopeless.

But still he had to try. 'Do what you like with me, but have pity on my son. He is very young. None of this is his fault.'

'What can we do?' The centurion sounded genuinely apologetic. 'The camp is surrounded. It is not down to us. Censorinus brought word that Aureolus wants you dead. He has put a price on your heads.'

The treachery of Censorinus hardly made any impression on Macrianus. A price on their heads. It meant exactly that. Decapitation, their heads paraded before Gallienus, their bodies denied burial. Somehow he had to stop the mutilation of his beautiful son. He could not think of the boy's soul wandering hopeless for eternity.

The muttering was rising in volume. Macrianus had to act quickly.

'You said yourself we had done you no harm. Let us take our own lives, die like the Romans of old. There is money hidden under the floor of the tent. Try to prevent them mutilating my son's body.'

The centurion nodded. He rapped out some orders. Some of his men went inside, others formed a ring around the big purple tent. Close by, the noise of revolution swelled.

'I am afraid you must hurry,' the centurion said.

Macrianus turned to his son. There were tears on the boy's face. He was making no noise, trying to be brave. Macrianus folded him in his arms. He pressed his lips to his neck, breathing in the smell of clean, fresh sweat, the smell of his son. He kissed him on the eyes, the cheeks, the lips.

The noise was growing. Macrianus somehow forced himself to let go of his son and step back. He drew his son's eagle-headed ornamental sword.

'Use mine. It will be sharper.' The centurion handed it over.

Macrianus took it. He looked at his son, and he knew he could not do this thing.

'You want me to do it?'

Macrianus gave the sword back to the centurion.

'Who first?'

Macrianus thought of watching his son die. He imagined his son watching him die, the boy left alone, terrified, waiting. 'My son.'

Macrianus stepped forward. He and his son kissed for the last time. Macrianus stepped back. In the imperial palace at Antioch, no one was sure if the consilium had started. Ballista was watching Quietus – not so as to attract attention – and so was everyone else. Titus Fulvius Iunius Quietus Augustus, Pius Felix, Pater Patriae, had ordered a large painting of Alexander the Great by Aetion hung in the audience hall. All his attention was on that.

Quietus's lips moved almost soundlessly. Everyone said he had been behaving oddly since the news had come about his father and brother. The following day Ballista had reached Antioch from Syria Palestina. When Ballista reported to Quietus, the emperor had given the impression that he was trying to look clean through him to see someone else. On their few meetings since, Quietus's gaze had slid off Ballista like water off a waxed cloak. Indeed, anyone remotely connected to the court had been acting strangely since the news from the west.

None had been acting more strangely than Julia. She had already shifted the familia out of the palace and back to the house in the Epiphania district before Ballista arrived. Her welcome had been reserved and, unexpectedly, physically reserved too. Afterwards she had made a comment about men marking their territory. She had said it on similar occasions before, as a joke, but this time it had a sharp edge. That side of things had improved a little since, but things generally were different, strained. Ballista wondered if someone had told her about the Persian girl Roxanne in Cilicia.

Quietus stopped muttering. He cocked his head to one side, eyes still on the painting. Allfather, thought Ballista, does he think Alexander is talking to him? It was a good moment to look away. It was a reduced consilium. Quietus's father and brother and their once-devoted supporter Piso were dead. Censorinus and Ragonius Clarus had deserted. The former had been appointed one of Gallienus's Praetorian Prefects, the latter told to retire into private life. But others from the east were missing. Trebellianus had withdrawn into the mountains of Cilicia Tracheia. Similarly, safe behind the deserts of Arabia, another governor, Virius Lupus, had not replied to the summons. Mussius Aemilianus, prefect of Egypt, had had himself declared emperor. As he was commander of quite sizeable forces and in control of the majority of the grain supply of Rome, his was not a hopeless revolt, but he would need allies. Obviously, Quietus would not be among them.

There were only two new faces on the dais. Quietus's nonentity of a cousin Cornelius Macer had been hurriedly appointed not only Comes Sacrarum Largitionum et Praefectus Annonae but Princeps Peregrinorum as well. Presumably the loyalty that blood might bring had outweighed any considerations of ability. Much more competent, standing near Ballista, was the tall red-haired figure of Rutilus, the new Prefect of Cavalry.

'Those who wear the likeness of Alexander in either gold or silver are aided in all they do,' Quietus said suddenly. 'My father often said that.' He pointed at the governor of Syria Phoenice. 'Cornicula, include that in your verse panegyric of them.'

Annius Cornicula bowed.

Now that Quietus seemed to be to some extent with them, unbidden, the senior Praetorian Prefect Maeonius Astyanax started talking. 'Dominus, there are reports, completely credible, that Odenathus is assembling his forces in Palmyra. Supplies have been stockpiled on the road west to Emesa. He is getting ready to march against us.'

Quietus put his head in his hands. 'What can be done?' His tone suggested nothing.

'Dominus,' Maeonius Astyanax continued, 'it can be prevented. I have met Odenathus. The two of us got on well. It is true he is avaricious. We have money. Let me go as an ambassador. With adequate funds, I can stop the Lion of the Sun, turn his bellicose attention back to the Sassanids. It would be a good time to attack them. Not only did the Persians suffer defeats last year, but Shapur faces revolts from subjects to the east near the Caspian Sea. If Odenathus attacks now, he may get as far as the Sassanid capital of Ctesiphon almost unopposed.'

'Let it be so.' Quietus looked up, brighter. 'Should your mission fail, we will rout this decadent oriental anyway.' He jabbed a finger at one of the governors standing in front of him. 'Pomponius Bassus, you have four legions in Cappadocia, auxiliaries too. You will raise more men. Hire Albanians, Iberians, Cadusii, nomads, Alani or whatever, from beyond the Caucasus. Raise an army fifty thousand-strong. Lots of cavalry. Fast-moving. You will move with all speed down the Euphrates. You will make Arete your base, then strike at Palmyra from the east. Odenathus will have to scurry back to meet you. We will be hard on his heels. With Odenathus caught between our armies, we will win a famous victory in the desert. The so-called Lion of the Sun will grovel at our feet. It will do him no good. We will serve him as Aureolus served our family.'

Quietus again relapsed into a preoccupied silence.

His face very still, Pomponius Bassus intoned the ritual words. 'We will do what is ordered, and at every command we will be ready.'

No one else gave any indication of what they were thinking. There were just two legions in Cappadocia, both under strength; a handful of auxiliaries. As Ballista knew only too well, the king of Georgian Iberia had marched with Shapur to the capture of Valerian – would he ever forget the cell in Carrhae? The Alani crossing the Caucasus mountains had long been one of the keenest fears not only of the Roman imperium but of every people living to the south, even of the Sassanid Persians.

Ballista followed Quietus's gaze to Aetion's painting. Alexander was standing in a bedchamber. His new bride, Roxanne, half reclined on the bed. Small erotes prepared her, tugging her clothes off. Others – lots of them – cavorted everywhere. Wings beating, they flew up to the ceiling, clambered over the top of the bed. On the floor they were playing with Alexander's armour. Even in bed with a new, beautiful woman, Alexander kept his weapons to hand, thought Ballista. Allfather knew what Quietus was thinking.

'Antioch on the Orontes,' said Quietus. 'Metropolis of Syria. We will turn her into an impregnable fortress. Let Odenathus come. Or Aureolus, or Gallienus himself. They will break their armies on the defences of Antioch the invulnerable.' He seemed to have already forgotten the happy fantasy of victory over Odenathus at the gates of Palmyra.

'Dominus,' said Ballista, 'Antioch is almost indefensible. The walls up on Mount Silpius are overlooked by natural rock. The city is not safe. Antioch has fallen to the Persians twice in a few years.'

Quietus glowered at him. He started to say something then stopped. He looked away.

'Dominus' – the client king Sampsigeramus spoke good Latin, if with an effeminate lisp – 'my city of Emesa is devoted to your cause – no city more so. No place in the east has better walls or other defences. We have supplies, money. Move the court and the army there. When Pomponius Bassus strikes from Arete, you will be on hand to ride out and defeat the upstart Odenathus.'

Ballista had to admire the way Sampsigeramus both hid his own desperation and played up to Quietus's fantasies.

'Whatever, whatever.' Quietus had lapsed into miserable introspection. 'What does it matter? Why not Emesa? We will go there. We will go there straight away. Give the necessary orders.' He looked up at the huge cedar beams of the roof. 'They mutilated them, you know. Sent their heads to Gallienus. They can never know peace.'

Quietus's imperial court and army were moving down to Emesa. They were six days out of Antioch, strung out for miles along the road running through the Mere of Apamea. The scenery here was unusual for the east: lush water meadows and wild reed beds as far as the mountains on either side.

Ballista called Maximus to him, leant close, kept his voice low. When he had finished, Maximus asked him to say it all again in case he had somehow misunderstood.

'Yes, you are to desert, slip away through the wetlands to the east. There are only a couple of miles to cross, but take care. In a rare moment of clarity, Quietus has ordered a large number of mounted patrols to sweep the rear and both flanks for stragglers and deserters. There are villages in the hills, so there have to be reasonable paths across them. Apparently, the hills are only about fifteen miles wide here. On the other side, you will strike the Chalcis ad Bellum to Apamea road: take the turning south from a village called Telmenissos. This will bring you to the upland road, through places called Theleda and Occaraba, to Palmyra. When you get there, find Haddudad. It should not be difficult; by all accounts, the ex-mercenary has risen fast in his new patria.'

Ballista smiled. 'The two of us saved Haddudad's life at the fall of Arete: call in the debt. Get Haddudad to arrange a private audience with Odenathus. It has to be done in secret, otherwise news will get to Quietus, and that will be the end of me and the familia. When you see Odenathus, give him this sealed message.' Ballista passed over a small package. 'Hide it in your scabbard. It is well wrapped in oilcloth, so should not come to any harm, not even if it gets wet.'

Maximus made to interject. Ballista held his hand up. 'No, it is better if you do not know what it says. If you are captured, you can play the simple messenger. Quietus will still kill you, but possibly not torture you for quite as long first. Apart from handing over the letter, the vital thing that you have to do is to make absolutely certain Odenathus knows which of the towers of Emesa is the so-called Tower of Desolation. You remember it? It is the tall, thin one at the extreme south-east of the defences. If Odenathus does not already know it, Haddudad will.'

Maximus nodded, thinking it over. 'Sure, if I can get away, we all could.'

Ballista looked tempted but shook his head. 'No, Dernhelm is too young, and Julia is a woman. I have heard of too many would-be fugitives from the imperium who have been caught because they were slowed down by women or children. Anyway, there is still something I have to do.'

It was mid-afternoon when Maximus rode away. It was a good time to choose, in any army, no matter how disciplined – and this one was not particularly disciplined – there is always confusion when it comes to pitching camp. There was nothing furtive about him as he set off. He rode purposefully east, away from the army. The very set of his shoulders suggested a scout or suchlike on official duty.

When he had gone a short distance he reined in and dismounted. Having hobbled his horse, he went behind a low clump of marsh plants, pulled his trousers down and squatted. As he pretended to relieve himself, he scanned everything. No sign of pursuit, and no sign of men up ahead. After a time he set off again.

Not far along the way, it happened. A problem with travelling wet lowlands was always the finite number of paths passable to men on horseback. Those that existed were often elevated and exposed. No chance of slinking along; you had to go where the track took you. Maximus rode through one of the infrequent stands of trees and came out on to a raised, open grassy area. There, scattered, taking their ease, were the men and horses of a whole turma of cavalry.

Maximus wondered if he should try and talk his way through. He was good at talking. Back home, he had not been known as Muirtagh of the Long Road for his travelling. Maximus kicked his heels into his horse's flanks. He thundered across the clearing. A standing trooper tried to block his way. Of its own volition, the horse skittered around him. The thirty-man patrol was dismounted. Maximus was in the saddle. It gave him a few moments' headstart.

Maximus bent low over his mount's neck, urging it on. Great clods of mud cartwheeled up behind as they fled. The path ran straight; it had to be manmade. It was raised high above the marsh. The tall, tall reeds only reached to the horse's belly. They had to be visible for miles. Behind, the roar of the chase was loud. Maximus had thrown away his shield. Crooning into his animal's ears, he raced on.

At last the track dipped down almost to the surface of the fen. It turned gently, first right then left. The feathery heads of the reeds soared high above them. Maximus hauled the horse to a standstill. Leaping down, he feverishly untied his kit bag. He parted the reeds to the left with his arm, then threw the bag out of sight. Quickly, he fastened the reins over one of the front horns of the saddle. He drew his sword and brought the flat of the blade across the horse's rump. Startled, it squealed and leapt forward down the path. Again with the flat of the sword, he parted the reeds a pace or two from where the kit bag had disappeared. He took a step in. The ground gave a little under his boots. The reeds closed behind him. Another sweep of the sword and another step. The trick was not to break or flatten any more reeds than absolutely necessary.

Just four careful steps, and the thunder of pursuit was almost on him. He was still too close to the track, but there was no time to get away. Maximus sheathed his sword and dropped down full length in the mud. He rolled on to his back, then on to his front again. He checked that his now muddied cloak covered his armour, and pulled off his helmet and pushed it, crest down, into a pool of dark water. Smearing mud across his forehead, cheekbones and nose, he waited.

The noise built to a crescendo: the stamp and slop of the hooves in the mud, the high ching of the horse furniture, the deeper rattle of the men's equipment. The air was full of the smell of horse. The reeds swayed with their passing.

Lying in the cool mud, feeling his boots filling with water, Maximus tried to count the hoofbeats: ten, fifteen, twenty horses. It was impossible. The sounds faded. Maximus did not move.

A butterfly, pale yellow, almost white, flew in and out of the reeds in front of his face. The smell of rotting plants was strong in his nostrils. The noise of horsemen came again: fewer of them, travelling more slowly, again from the west. Maximus had guessed right. The majority had hared off after him while a few were following at a more leisurely pace in case he broke cover after the first lot had gone. Fuck you, he thought triumphantly. Fuck each and every one of you.

As soon as the horsemen passed, he got to his feet. Relying on their noise covering his, he plunged off to look for his kit bag. The leading group would overhaul his riderless horse all too soon. He splashed to where the bag lay, half submerged. Infernal gods, he had forgotten the helmet. Fuck it, no time. He turned to get deeper into the marsh.

The kit bag was heavy and incredibly awkward. If he held it upright, there was a danger it might show above the reeds. If he held it sideways, it would reveal his movement through them like a wave. Somehow trying to judge which tangles of vegetation would at least temporarily take his weight, he struggled along with the horrible thing jutting out in front of him.

Shouts, the noise of horses. They were coming back. Again Maximus dropped to the sodden ground. As soon as he had, he knew he had chosen a bad place. There was more water than soil or vegetation, and he was in mail armour. The liquid mud slowly but terrifyingly started to suck him down. Making a long arm, he dragged the kit bag to him and up under his chest. With his arms spread along it, his weight was more widely distributed. It was better, but it would not do for long.

'Come out, you cocksucker.' The voices were very close. 'Little Quietus will not kill you. He needs every one of us alive. Maybe he will just give you a stern talking to, send you back to duty with a sore arse and a nasty taste in your mouth – all the stuff you like.'

Shouts came from all along the path. They were walking their mounts back, probably in single file. Some called out. All would be watching the fen.

'Get your saggy arse out here, bumboy. If not now, when we catch you, we will all give you what a cinaedus like you wants.'

The sexual insults and obscenities amused them for some time. Eventually, though, they fell quiet. A lone voice, obviously that of their decurion, rang across the sedge. 'We will be back. If the mud has not swallowed you, we will get you. We will be back with dogs.'

After they had gone, Maximus levered himself up and sat on the mainly submerged trunk of a long-fallen oak. He had not been too worried about the threat of dogs. Most Romans used dogs that hunted by sight. Very few knew how to use dogs that hunted by scent. In any event, it would have to be an exceptionally fine hound that could track a man through this waterlogged wilderness. He would be long gone if they ever returned.

After a childhood and youth in Hibernia, marshes held few fears for Maximus. Certain, you had to treat them with respect. Many was the man who had thought the footfall solid and been sucked down to his death. Often at night their souls wandered, flickering lights, trying to lure others to their fate. Was it malice, or were they just after company? Maximus had never been sure.

He sat there regarding the kit bag. It was horribly heavy, more so now soaked, unwieldy too. Did he really need it? Was there anything precious in it? He had his weapons and armour, plenty of money in his belt, Ballista's letter. He wondered if it was good or bad to have so few possessions he cared anything about. If Demetrius had been there, certain he would have started to spout philosophy: the virtues of self-sufficiency, or some such shite. Plilosophy was something Maximus was sure he did not need. He got up, rummaged in the kit bag for some air-dried beef and left the thing behind.

For most of the remaining daylight hours, he made his way, as far as he could tell, north-east; away from the track, but still towards the mountains. Every now and then he had a view of them: a darker line of blue below the pale blue of the cloudless sky. He remembered how Ballista had called them hills; made crossing them seem all the easier.

As the afternoon wore on, he came to a mere of open water. Its surface glittered beautifully in the sun. It lay north to south. It was between him and the dry land at the foot of the mountains, and it stretched as far as the reeds would let him see. It was only about a hundred paces across, but he had no intention of trying to wade or swim it. A mere like this might be bottomless mud, like the one at home they used to drown the buggers in. You could be sure this mere was full of vegetation waiting to tangle and trap your arms and legs. And what would he be doing with his armour? The path with the cavalry was to the south; he had set off north.

When the shadows began to lengthen, Maximus had scouted for a flat, dry place to lay his head.

He woke the next morning: caked in dried mud, flies all over him, only some dried meat to eat, and still stuck somewhere in the Mere of Apamea. The main road south from Antioch to Emesa could not be above half a mile away. Lying in the reed beds, Maximus could not see it. He was very still, listening, watching. The dry rustling of the tall reed beds moving was all he could hear.

Maximus filled in the shallow hole he had dug by the shore of the little lake and thought about the Persian boy Bagoas, years ago, telling him it was forbidden for Magi to foul running water. Would they relieve themselves in a non-flowing peat lake? Looking at the surface of the mere gently rippling in the breeze, it would be a shame. Better by far to bury your shit. And that way it was hard for your enemies to track you too.

After about half an hour, he came to a causeway. It ran straight as an arrow across the mere. On the far side, Maximus could see fields and a path grading the slopes, signs of terracing higher. On the nearer side, it connected to a well-made-up track. Over the track were fenced water meadows. He had reached one of the parts of the Mere of Apamea more tamed by the hand of man.

Yet as he lay in the reeds watching, there was not a person in sight. Actually, there were very few living things at all. At home, a fen like this would have been alive with wildfowl and all sorts. Out here in the east, you seldom saw many birds. Where had they gone? Had the luxury-loving locals eaten them all?

No point in waiting any longer, Maximus climbed up and set off.

When he was virtually at mid-point on the causeway, the two horsemen materialized at the mountain end like some unwelcome divine epiphany. They were trotting towards him, and they were in Roman uniforms.

Swearing quietly, Maximus looked behind him – too far to run – and to either side – just the glittering mere, the shining face of a dark fate. He stood still and waited for them. It was a shame, more than a shame it had to be this way.

The horsemen reined in some paces away. Their swords were drawn. They did not speak. The one on the right dismounted first, then the other.

'Drop your weapons.' The first to dismount spoke.

Maximus unclasped his cloak. As he dropped it off to his left, his eyes never faltered from the nearer soldier. No opportunity came – the soldier's gaze stayed on Maximus.

'Weapons.'

Maximus unbuckled his sword belt, shrugged the baldric off his shoulder and tossed them after the cloak. Again the soldier's gaze did not waver. This was not going to be easy. Maximus still had old Calgacus's trick in his boot. But he was running out of options and time.

The first soldier stepped forward, his blade at Maximus's throat.

'Not a good day for you, deserter.' The other one spoke.

You should keep quiet, like your friend, thought Maximus.

'Hands out. Wrists crossed.' The first was in charge.

Maximus did as he was told.

The first soldier glanced at his belt, going to free the leather strip to bind the prisoner.

Maximus took the edge of the sword on the right sleeve of his mail coat, pushed the point away. Stooping, with his left hand he drew the dagger from its sheath in his right boot. Staying low, he drove it into the soldier's right thigh, just below his armour.

The other one was on him, sword arcing down. Maximus only had the dagger to catch the long blade of the spatha. Most warriors, no matter what their training, shut their eyes at the moment of contact. Maximus forced himself to watch the blade. He blinked. The sound of steel on steel. The impact ran up his arm. Automatically, he rolled his wrist. He opened his eyes. The sword was being deflected wide.

The momentum of Maximus's opponent was carrying him past, slightly off balance. Maximus spun elegantly and kicked him hard behind the left knee. The man went down. Maximus pounced. He landed with all his weight on top of the soldier. Grabbing the man's helmet, Maximus forced his face down into the mud. The man thrashed about, the viscous black liquid pushing into his mouth, his nose. Maximus increased the pressure.

Maximus glanced at the first soldier. He was inching in agony towards the sword he had dropped. His thigh was running with blood. No immediate threat there.

The struggles of the man in the mud began to weaken. Maximus pushed down as hard as he could. A convulsive series of movements, and then nothing. Maximus did not ease up for several moments.

Finally, the other soldier was nearing his sword. When he got up, Maximus's legs were stiff. With a hobbling run, he crossed the track. He kicked the sword away from the desperate hand. Falling to his knees, he seized the man's chin, yanked it back. He wielded the dagger. There was a rasp of metal on metal as the edge of the blade slid down the nasal of the man's helmet. The tip of the blade entered the eye. The man jerked up rigid, went still.

Maximus got up, looked both ways. No one in sight. He felt an odd tiredness and lack of urgency. He forced himself to think quickly and get moving. Having cleaned the knife, he put it back in his boot. He went over and put his sword belt on again. At the side of the track, he washed the blood off his hands and arms in the mere. He picked up the leather thong that had been intended to bind him. Maximus had always been good with animals; the horses came to him, wary as they were of the smell of gore on the ground. He hobbled the first one with the piece of leather. Horses were herd animals, and it did not really matter if the other happened not to stay.

The man face down in the mud had a cloak of pale blue with a fancy gilded clasp. It appealed to Maximus, so he put it on. He tried the man's helmet, but it did not fit. He spread out his own muddied cloak and dropped the helmet in the middle of it. He went back to the dead man and searched him. The reasonable sum of coins he added to his own purse. He drew the man's sword and tossed that on to his cloak as well. Then he dragged the corpse to the edge of the causeway and rolled it into the water.

Maximus went over to the other man and – except for the cloak – repeated what he had done. When the water stilled, Maximus could see that this second corpse had settled partly on top, partly beside the other. They were not well hidden, but it was better than nothing.

The unhobbled horse had remained with its companion. The soldiers' shields, with their unit identification, Maximus unhitched from their saddles. They were added to the pile on his abandoned cloak. He tied the corners together and threw it as far as he could. In the water, it darkened, settled, then sank.

Maximus talked gently to the horses as he altered the hobble to a leading rein. Their breath was sweet on his face. He got into the saddle. He studied his work. The surface of the causeway was ploughed up and bloody. The mud would soon take care of that. The corpses were not deep enough to be invisible, but if you were not looking you might not notice them. It was a shame, more than a shame he had had to kill them. They had just been doing their duty. But then so was he. Turning the horses' heads, he trotted away towards the east and Palmyra. It was eight days since Quietus's court and army had arrived in Emesa. Time for Ballista to rent a house, for the familia to begin to settle in. Time for Ballista to begin to hope that Maximus had got away, that things would work out.

The boots in the street woke Ballista. When they stopped, he slipped out of bed. It was very dark, probably well past midnight. His hand closed on the scabbard of his sword, hanging in its accustomed place.

The pounding on the main door boomed dully through the house.

Ballista pulled on a tunic and opened the door of the bedroom. Light came in from the corridor. Julia was sitting up in bed. She did not say anything, but her dark eyes looked frightened.

There was more pounding on the door, a muffled shout.

'It will be fine,' Ballista said.

Actually, he had no idea. There were troops outside. Roman soldiers walked differently to anyone else. But it could be anything. Emperors, especially erratic ones like Quietus, could summon men to their consilium at any time of night or day. There, by lamplight, while the rest of the world slept, they might be called on to discuss anything from war in the east to the best way to cook a fish. Even under Quietus a nocturnal consilium was not necessarily something to fear, and it would be most strange if, as one of the two serving Praetorian Prefects, Ballista was not summoned. But there again, no one in the imperium would feel completely safe when the soldiers hammered on the door gone midnight. It could mean something altogether different.

'It will be fine,' Ballista said again.

Julia did not reply. There was something wrong with her, had been since he came back from Palestine. In the old days, she would not have looked frightened, even if she had been terrified. In the old days, she would have spoken to him. Mostly, she was the same, but something had changed. He did not know what.

More pounding on the door. From the depths of the house came the wheezing voice of Calgacus in full peevish flow. 'Middle of the fucking night, fucking hold your fucking horses, you will have the fucking thing off its hinges.'

Ballista went out on to the balcony that ran all around the atrium at the first floor. He walked to the stairs that faced the entrance and waited. He found he was shivering. Maybe, even in Syria in high summer, there was more of a chill to the night than he thought.

Calgacus appeared, holding a lamp for a centurion. They were followed by about twenty Praetorians, who fanned out around the courtyard. Too many soldiers for anything but bad news. Ballista had known from the start but had failed to acknowledge it. He did not know what had caused this, but if Maximus had been caught, this was the end. Ballista battened down his fear.

Ballista was puzzled to see a centurion that he did not recognize. In the reduced numbers of the Praetorian Guard of Quietus, there were not that many of them. Yet the centurion looked familiar. If Demetrius had been there, he could have put a name to him.

'Dominus,' said Calgacus, 'this is Marcus Aurelius Jucundus.' The Caledonian's face was woeful.

Ballista did not recognize the name either.

'Dominus.' The centurion's tone was stiff, official. He read from a papyrus roll with a purple seal. 'The order of the most noble Caesar, Titus Fulvius Iunius Quietus, Pius Felix, Pater Patriae, Restitutor Orbis, Invictus. Marcus Clodius Ballista is relieved of his command as Praetorian Prefect. Furthermore, he is to be placed under arrest immediately and conveyed to the central gaol under the palace of the kings of Emesa.' The centurion paused. Very quietly, he said, 'I am sorry, Dominus.' Presumably that was not written on the papyrus. He took a breath and continued. 'The barbarian is to be confined there at our pleasure… together with his wife and his sons.'

The centurion was most kind, consideration personified: they could have time to collect some things, as much as they needed, could take what they wished. They roused the children. At two, Dernhelm was too young to understand. He smiled at the lights glittering and moving in the Praetorians' armour then fell asleep on his mother's shoulder. With Isangrim, a thoughtful nine-year-old, things were different. Ballista spoke to him alone. Isangrim must be brave as an example to his younger brother, and to his mother. Isangrim and Ballista must be brave for each other. The boy nodded. He stood, straight-backed, a slight tremble to his chin. Father and son embraced. Ballista told his freedman Calgacus that he was in charge of the remaining familia; the accensus Hippothous would help him supervise the porters, cooks, maids owned or employed in the house. Ballista and Calgacus embraced.

As they walked through the darkened streets, Centurion Jucundus said he had been to see the gaoler before coming to Ballista's house. He had instructed the man that Ballista's family were to be allocated the outermost cell – it had a little natural light and ventilation. By now it should have been scrupulously cleaned and given furniture. The prefect and the domina could have their servants bring them any food or anything else they liked. Jucundus himself, or one of his men, would come every day to check that everything was as well as the circumstances permitted. It was notable that Jucundus still employed Ballista's title.

Reaching the palace, passing through its dark, squat walls, under its fantastic, soaring towers, all was as the centurion had said. Lamps were lit in the cell. There was a bed, a table, a few chairs. The bare walls and floor were clean. It had been scented, although nothing could quite mask the underlying prison stench.

Julia, her brisk, capable self again, was in constant motion, putting the children to bed, unpacking their hasty possessions, instilling order.

At the door, Ballista thanked Centurion Jucundus for his trouble.

'It is the least I could do, Dominus. The new prefect Rutilus – your replacement – promoted me into the Praetorians late yesterday. All my life, man and boy, I have been with Legio IIII Scythica. I served under you, in the ranks of Castricius's vexillatio, at Circesium. You never got the credit you deserved for that victory.'

Ballista smiled. 'I thought you looked familiar.'

Jucundus smiled ruefully. 'Castricius – a long time ago he was my contubernalis – has been appointed to replace Rutilus as Prefect of Cavalry. Not done badly, old Castricius, for a man who was once in the mines.'

Ballista also smiled. 'He is a resourceful man.'

'That is one word for him. I remember that night at Caeciliana – gods below, the two of you were drunk – when you burned that patrician officer's baggage. The boys and me could hardly stand for laughing. It was magnificent.'

Ballista dropped his voice. 'Jucundus, has my freedman Maximus been arrested?'

Jucundus shook his head. 'Not that I have heard.'

Ballista sighed. 'That is something at least.'

'I will see you tomorrow.' Jucundus snapped a salute, incongruous in the degraded surroundings.

Jucundus turned back. His eyes took in the small cell. 'Your wife and children too… Dominus, I am so very sorry.'

The dead lived well in Palmyra. Maximus rode through the Valley of the Tombs; everywhere, the tall, well-built rectangular homes of the dead. Maximus had been this way before, six years previously, on his way to Arete. One of a company then, he had not really looked at the tombs. Alone now, he gazed at them. They spoke of wealth and power. And, to his mind, there was something more. Halfway up the steep slope on one side, three, four storeys tall, their masonry so well squared off, doors and windows so neatly cut, the ring of towers spoke of permanence. They were like a smoother version of the jagged rocks poking through the sand at the summit; grown out of nature, but shaped by man. Like the living rocks, they intended to be here for ever.

Looked at in a certain way, they seemed to be the walls, the natural rocks the city; the dead men guarding the living rocks. Gods below, any more of this drivel and you would think I had been educated in Athens, thought Maximus. He had been out in the sun a long time. It had been a long, tough journey since the killings in the mere. Over the terrible hard mountains – Ballista's bloody hills – then monotonous days of dun-coloured, sun-blasted, rocky desert. But at last he was here: Palmyra, Tadmor to the locals, the oasis city of Odenathus, the Lion of the Sun.

There was a crowd at the gate jostling to get in. Most were farmers from the villages to the north-west, their donkeys, camels and wives laden with wheat, wine and fodder, olive oil, animal fat and pine cones. There were fewer traders from the west than there had been the last time Maximus had been here. But there were a couple. War or not, profits can drive a man from home. One of these hardy souls traded in Italian wool, the other in salt fish. It was very hot, and tempers were short. Men shouted and donkeys brayed; the camels spat.

Maximus sat on one of his two horses and looked at the city walls. He remembered his old drinking companion Mamurra sneering at them the last time they were here. The Hibernian checked the thought – as if that square-headed bastard Mamurra would ever be going anywhere again, buried as the poor bugger was in a collapsed siege tunnel under the walls of Arete. He was never the quickest man in the world, old Mamurra, but in time he had got things right. The low mud-brick walls of Palmyra would be as much use in a siege as a one-legged man in an arse-kicking competition. It was a good job the Palmyrenes were on the attack. They had better pray the tables were never turned.

Eventually, Maximus reached the customs post in the gate.

'What do you have to declare?' The telones spoke without looking up.

Maximus did not reply.

With a tut of irritation, the telones took his eyes from his tally. He took in the mail coat; the worn leather grip of the sword; the missing tip of the nose; the two horses and the dust engrained thick in everything that told of a long journey at speed. 'Carry on,' he said. 'Next.'

Inside the gate, Maximus threw a street child a coin and said he wanted the house of Haddudad. He followed the lively bundle of rags and brown limbs up one fine, bustling colonnaded street, down another, through a monument of sixteen columns of swirling black and gold, passed a full agora and an empty theatre. The strong but not unpleasant smell of spices, horses and humanity, all with a slight edge of camel, was familiar. Maximus recognized the route to the palace of Odenathus. Three houses beyond it, his guide stopped, pointed at the marble entrance to a huge townhouse and jabbered excitedly in whatever language he or she spoke. Haddudad the mercenary had come up in the world.

Maximus showed the child – on balance, probably a girl – a quite high-denomination coin, mimed holding the horses and put the coin back in his wallet. Laughing, the child took the reins.

The porter created no fuss. It was as if armed, violent-looking men covered in dirt arrived at the door every day. Given that his kyrios was an ex-mercenary and his kyria the daughter of a caravan protector, quite possibly, they did. He showed Maximus to a small room and asked him to wait. He expressed no surprise when the visitor declined his offer to look after his weapons.

Maximus sat down and stretched out his legs. He assumed he was being watched. He looked around, unconcerned. The walls were painted and depicted some Greek myth. Large, near-naked and hairy men were running about on an improbable range of mountains. They were throwing huge boulders down at anchored warships. Most of the ships had been hit, and some were already beyond salvation. Their crews stretched their hands to the heavens in appeal or reproach. A shifty-looking man on the last vessel had the right idea. He was cutting the mooring rope. The galley was so far unscathed but, given the hairy boys' skills with a rock, Maximus did not fancy its chances.

Two armed men entered the room. Hands on their hilts, they hard-eyed Maximus. After them came a woman in eastern costume, fully veiled, only her eyes visible.

Maximus politely stood up. The guards tensed.

The woman passed the guards, came close. With her left hand, she reached up and across and undid her veil. Gods below, but Bathshiba was still attractive.

'It has been a long time,' she said in Greek. Her voice was as he remembered; the sort of thing that could take a man's wits.

'Five years.'

'I would kiss you, but you are filthy.' She smiled, stepped back.

Ballista, my old friend, thought Maximus, you were a fool not to fuck her when you had the chance. If it had been me she set her cap at in Arete, her bed would have been no place of solitude and quiet contemplation.

'As you can see, I am in my best demure-wife clothes. We are entertaining – just the one guest. You will join us; no need to bath or change.' She came close again, closer than before. He could smell her, beneath her perfume. Ballista, you were such a fool. She leant closer still and, her breath in his ear, whispered, 'Be very careful what you say in front of Nicostratus. No mention of coming from the army of Quietus. No mention of Ballista.'

The dining room was light and shady at the same time. For a Syrian afternoon in high summer, it was cool. A water feature played somewhere.

Haddudad rose from his couch. Prosperity suited him. His hair was longer, flat on top, curled at the sides, very artful. From behind his full, curled and perfumed beard, he grinned.

'Maximus,' Haddudad said. Although his clothes were yet more gorgeous and ornate than those of his wife, he hugged the Hibernian to him. They pounded each other on the back. Clouds of dun-coloured dust drifted up through the shafts of sunlight.

Haddudad gestured at the occupied couch. 'Maximus, this is the renowned historian Nicostratus of Trapezus.' Haddudad gestured back again. 'Nicostratus, this is an old systratiotes of mine from the siege of Arete, Marcus Aurelius Maximus.'

The man of letters got to his feet. There was no overt show of reluctance, but Maximus had the impression that Nicostratus of Trapezus did not often shake the hand of mercenaries, old companion of his host or not.

Servants brought in a third couch. Haddudad guided Maximus over to it. All three men reclined. Bathshiba sat on an upright chair behind and at the foot of her husband's couch. Maximus felt like laughing. He remembered the wild Amazonian girl from Arete: dressed like a man, fighting alongside her father's men, quite probably – much to his fury – saving Ballista's life.

First they brought him a bowl and ewer to wash his hands. Then a servant positioned a small table at Maximus's right hand. Another placed a selection of small dishes of pastries, olives and cheese and an empty wine cup on the table. A third poured the mixed wine. Maximus made a libation and drank the health of his host.

Haddudad and Nicostratus resumed a conversation they had obviously been having before Maximus arrived. It was about a historian called Herodian. Nicostratus tried to include Maximus. The Hibernian said he was usually paid to kill men not read books. Nicostratus did not try again.

Maximus drank his wine. He was impressed by Haddudad. The ex-mercenary had taken to this life as if born to it. His fine, embroidered tunic, trousers and boots – all dusty now – hung easily on him. He lounged elegantly and was more than holding his own in bookish discussion: 'So would you agree, my dear Nicostratus, that Herodian sacrifices certain trivial details in order to bring out more clearly what he regards as deeper and more profound levels of historical truth?' The false nomen he had given Maximus was clever. Since the emperor Caracalla – about fifty years earlier – had given Roman citizenship to all the free inhabitants of the imperium who did not already have it, almost every other person carried the Caracalla's praenomen and nomen: Marcus Aurelius.

A servant came and refilled Maximus's wine cup. That was another creditable thing about Haddudad – not just that he kept the drink flowing but that he had followed Bathshiba's father's way of employing fighting men at table. Much more use than some pretty boys or naked girls in the event of trouble.

Bathshiba leant forward and spoke to her husband. Haddudad inclined his head, smiling. She got up. At her sign, a servant placed another upright chair by Maximus's couch.

'Historiography not your strong point?' Bathshiba's voice was pitched low, so as not to carry. She did not wait for an answer. 'Nicostratus is a pompous bore – failings not unknown among men of his calling. Zenobia summoned him here to Tadmor. She has commissioned him to write a history from the reign of Philip the Arab to the glorious victories of Odenathus. It will be ghastly – no chance of it standing the test of time.'

Maximus studied the reclining Greek historian. He had thin, pursed lips in a self-satisfied face. He did not appear a man much troubled by curiosity. Under his Greek himation, a pair of oriental embroidered trousers and finely tooled soft leather boots peeped out. This standard bearer of Hellenic culture had gone half native already. Not that Maximus cared.

'Odenathus's second wife is not the beautiful but submissive young girl we were all expecting. Zenobia is deeply ambitious. More ambitious even than Odenathus himself. And she is warlike.'

Maximus glanced sharply at Bathshiba, who ignored it.

'It frustrates her. Odenathus has a grown son, Haeranes, from his first marriage. The young man is a natural warrior. In Zabda and Zabbai, Odenathus has two generals he trusts. Now there is my husband. No need for a twenty-year-old girl in the councils of war of the Lion of the Sun.'

Bathshiba stopped as a servant replaced the empty dishes with ones of fruit, nuts and sweet things.

'So,' she continued, 'Zenobia has set herself up as the great patroness of culture. From all over the east, philosophers and sophists, historians and poets, flock to the court. These men of paideia infest the palace. Every one of them is more greedy and ambitious than the last. But every one of them owes his position to Zenobia. And that is why Nicostratus is here, and why poor Haddudad is putting himself out to be so charming.'

Bathshiba smiled charmingly as Nicostratus looked around.

'Not that Zenobia does not get to ride with the army.' Bathshiba's eyes sparkled with her old mischief. 'They say she will not let Odenathus have what a husband needs unless he lets her have her way.'

The last tack of her conversation sent Maximus's thoughts wandering. Under all these eastern fabrics, was Bathshiba still the nicely rounded armful she had been? She had been one of the likeliest-looking bits of tumble you could imagine. Lucky old Haddudad.

'Ow.' She had prodded him with a fruit knife. Maximus quickly smiled blandly over at the others.

'That is better. My face is up here.' Bathshiba's teeth were very white when she laughed. 'And I said, what are you doing here?'

'Ballista wants Haddudad to arrange for me to see Odenathus in secret.' There was no point in beating around the bush.

'Why?'

'To give him a letter.'

'Saying what?'

'I have no idea.'

'Really?'

Maximus looked at Bathshiba. Surely she was not being so unsubtle as to push her shoulders back to accentuate her breasts. How shallow did she think he was? 'All I know is I have to make sure Odenathus knows which is the Tower of Desolation at Emesa.'

'The tall, thin one at the extreme south-east of the walls.' Bathshiba spoke, but her thoughts were elsewhere. 'Of course Haddudad will do it. But…' She paused. 'I am not sure what sort of a reception you will get. Your friend is a leading general of Odenathus's enemy. Obviously, much depends on the contents of the letter. But it is far easier to read Herodian's History than the Lord of Tadmor. He is unpredictable. It is part of what has made him so powerful. He is like a capricious elemental force. The Lion of the Sun may shower you with gold and make you his drinking companion – or he may kill you like a dog.'

Maximus shrugged. 'Sure, life would be terrible dull if we knew all the outcomes. Is there any chance of a bath?'

'Of course. Would you like some company?' At Maximus's grin, she quickly added, 'No, not me, you fool. One of the maids.'

'Well, that would be better than either your husband or the historian. I don't suppose there would be two of your maids at a loose end?'

Before she made the arrangements, Bathshiba spoke seriously one more time. 'It is lucky you have come now. You are nearly too late. The Lion of the Sun marches on Emesa in three days.' It may have been the best cell to be found in the gaol under the palace of Emesa, but it was still dark, airless and insufferably hot. And familiarity did not stop the stink of it catching in Ballista's throat.

Ballista knew he had failed. Everything he had done during these years in the east had been to protect his family, and he had failed. He did not know why, but they were in gaol with him.

True to his word, Jucundus, or one of his men, had come every day to check that things were no worse than they had to be. This may have gone some way to explaining why the behaviour of the gaoler and his assistants had shifted from its customary and ingrained cruelty to a grudging near-politeness. The open-handedness of the prisoners with money and an unexpressed and incoherent fear of the mutability of fortune probably also came into play.

Under the supervision of Calgacus, servants delivered fresh food and drink. Every morning, maids dressed the hair and did the make-up of the domina. Other girls produced newly cut flowers. The women swept and cleaned, strategically arranged the flowers, lit scented lamps and liberally dispensed scented oils. Yet, no matter how many aromatics were deployed, still the prison stench seeped up from the lower cells, where those lacking in fortune and influence lay in their own filth, devoid of hope.

The children were doing surprisingly well. Admittedly, they had no fresh air, nowhere near enough space to run, and sometimes their own noise crashing back from the walls seemed momentarily to stun even them. But they had the rarity of near-undivided attention from their parents, all their favourite playthings, and were largely being fed things of their own choice. To all these benefactions, Isangrim added the absence of his schoolmaster.

If the boys were bearing up well, the same could not be said of Julia. Her usual disposition towards order had been elevated almost to the level of mania. She was always moving, tutting and complaining under her breath as she put things back in their right place after her husband or children had moved them. It was, thought Ballista, rather like being locked up with a better-looking version of Calgacus, but with his irony gone.

Ballista himself, as far as he could in the din of the confined space, retreated into reading. The second day, he had Calgacus bring him Arrian's Discourses of Epictetus. It was hard to think of a circumstance where some hard-line Stoic philosophy should not be more appropriate or sustaining. On the third morning, as instructed, the Caledonian arrived with a novel, The Aithiopika of Heliodorus of Emesa. Ballista wondered if he might learn some interesting things about the mentality of the town in which he was a prisoner. He did not. But it was a diverting enough series of picaresque stories within stories. After another day, he asked Calgacus to bring him some of Plutarch's Parallel Lives. They were far more like it – examples of men bearing changes in fortune set in exciting stories; philosophy in action for those like Ballista who could not quite stomach the unalloyed thing. He started with the lives of Demetrius and Antony: Antony turned back to Rome. He disguised himself as a slave, made out he was carrying a letter to Fulvia from Antony and was admitted to her presence with his face all muffled. Fulvia was distracted and, before taking the letter, asked him whether Antony was alive. He handed it to her in silence, and no sooner had she opened it and begun to read it than he flung his arms around her and kissed her.

'Dominus.' Jucundus stood in the doorway. 'I am ordered to convey you to the sacred presence of our emperor. Your wife and sons are to remain here.'

There was only time for hurried farewells. Julia looked openly terrified, and her fear transferred itself to the boys – Isangrim cried, Dernhelm howled. An inauspicious way to leave.

Quietus was in the great temple of Elagabalus. As they marched through the streets, Jucundus, talking out of the corner of his mouth like a legionary on parade, said he had no idea what the summons portended.

When they had reached the sacred precinct and were rounding the altar, Ballista and his escort had to check their progress. A procession of members of the Boule of Emesa crossed their path. The councillors were clad in formal Roman togas, the majority with the narrow stripe of an equestrian, one or two with the broad purple denoting senatorial status. Each carried on his head a golden bowl of reeking intestines. Try as they might, the local worthies could not prevent the odd slop of blood landing on the snowy-white material of their robes.

Ballista took in his surroundings. The three fires on the altar hissed and spat, burning unnaturally bright colours: blue-green, yellow, red. Slaves were busy spreading clean sand on the ground. Mingled with the smell of incense were the stench of unwashed tripe and the powerful tang of urine. Flies buzzed thick in the air. The bowls on the head must be an Emesene particularity, but everything else could not be more normal: the aftermath of sacrifice, the imperium-wide mundanities of conventional piety.

A silentarius took charge of them at the foot of the stairs. After the bright sunlight, the interior of the temple was dark, cavernous. It stretched away, echoing into infinity.

In the gloom, a line of pinprick lights. As Ballista's eyes adjusted, these resolved themselves into a row of ornate candlesticks dividing the great room, dividing the sacred from the profane. In the middle of the row, on its small, portable altar, the imperial fire burned; beyond them, the golden statue of an eagle. It stood confident on its wide-spread legs. The many little lights slid over its mighty, outstretched wings, over the snake writhing in its cruel beak.

Beyond the eagle, seemingly hanging in the air, was the imperial throne. Quietus sat in it, as still as a statue. He was dressed all in purple and gold; a voluminous tunic and a tall tiara; innumerable jewels. His painted face was immobile.

And beyond Quietus, looming over everything, was the god himself. Elagabalus, the great black stone that had fallen from the heavens, towered up towards the shadowy ceiling. Impossibly dense, it drew what light there was into itself. Only the occasional little rill of light splashed across the god, animating the mysterious markings in the depths beneath his smooth, dark surface.

Neither emperor nor god took any notice of the newcomers. As Ballista and his escort rose from their proskynesis, the silentarius ushered them off to one side. There they waited.

There was a sudden clash of cymbals. From somewhere, the music of flutes and pipes: high, twisting, intricate. Sampsigeramus, the priest-king of Emesa, danced into view. Apart from his necklaces and the many bangles on his wrists and ankles, he was naked. His body was thin, almost emaciated, the veins unnaturally prominent. Palms up, he danced before the emperor and the deity. To Ballista, there could not have been a more stomach-turning picture of eastern servility and effeminacy.

A high, shrill cry, and the act of worship was completed. Sampsigeramus went and sat on a low chair by Quietus. The emperor's non-entity cousin, Cornelius Macer – now the holder of three high government posts – was on the other side.

'Bring in the atheist,' said Quietus.

The Praetorian Prefect himself, Rutilus, brought in the prisoner. It was the tall, severe-looking senator Astyrius. They performed proskynesis. Quietus looked at the prisoner. The silence lengthened.

Astyrius was dressed in Greek himation and tunic, rather than his senatorial toga. He kept his hands clasped in front, eyes modestly downcast. Only a tiny tremor in his legs betrayed the doubts and terrors he must be feeling.

'Tell me' – Quietus's voice was light, conversational – 'have you been wondering where your pretty slave boy Epaphroditus has got to?'

Astyrius did not answer.

'No! Really, not at all?' Quietus raised his painted eyebrows. 'No concerns for his wellbeing? Not even considering the secrets the two of you share?'

Astyrius opened his mouth, but words failed him.

'Well, let me tell you anyway.' Quietus was enjoying this. 'At the moment, it must be said, he is probably none too comfortable. He is in one of the deepest dungeons under the palace. Although that is unlikely to be his main concern. Because your young friend, or should I say brother, is riding the equuleus. Have you ever seen the wooden horse in action? It is most ingenious. It must be agony for your pretty boy as the pulleys force his limbs apart.'

Astyrius made a small choking sound, then controlled himself.

'Not that he is all that pretty any more.' Quietus laughed. 'In fact, he is rather repulsive. You would hardly recognize him.'

The emperor stopped talking and peered closely at Astyrius.

'I am not sure what it is about your physiognomy, but I have never liked the look of you. Never trusted you. So I had the frumentarii lift your little boyfriend Epaphroditus from the baths. We hung him up – by one hand actually, much more painful – and while beating him – just the usual rods, thongs, whips – asked him some questions about you. Do you know, he would not say anything. You would have been very proud of him.'

Astyrius had mastered the trembling in his legs.

'And then the strangest thing happened,' Quietus continued. 'We got the claws to work on him. It really was terrible the way they were stripping the skin from his sides. But as he still refused to incriminate you, I suggested the torturers went to work on other bits of him: stomach and thighs, the soles of his feet, his pretty cheeks and forehead. And that was when he cried out: "Even murderers are not treated like this, only us Christians."'

Quietus smiled at Astyrius. 'Well, you can imagine how that encouraged us. We pressed on with a will. When I was at Ephesus, I discovered the pleasures of interrogating Christians. I even offered your little slave boy his freedom if he would admit you were a Christian. The impudent little cinaedus replied, "I have been freed by Christ." So once again you Christians, not content with denying the gods, stand convicted of attempting to undermine all property rights here on earth.'

'I am a Christian,' Astyrius said.

'Is it true you have sex with your sisters?'

'I adore Christ. I detest the daemons. Do what you will. I am a Christian.'

'And eat specially fattened babies?'

Astyrius squared his shoulders. 'I am a Christian. It is better to die than to worship stones.'

'You are about to find out if that is true.' Quietus signalled to the Praetorian Prefect.

Rutilus pushed Astyrius to his knees. The Christian did not struggle, but he called out, his voice powerful, 'You have condemned me, but God will condemn you. You will fall as the stars of heaven are swept down to earth by the dragon's tail.'

Rutilus drew his sword.

Astyrius leant forward, offering his neck for the blow. 'The devil goes about like a roaring lion, seeking whom he may devour.'

Rutilus raised the sword.

'It is for you, Christ, that I suffer this!'

The sword fell. It was a neat stroke.

Astyrius's head fell heavily, wetly, to the floor. It rolled an uneven two or three turns towards the row of lit candles. For a time his trunk remained, four distinct jets of blood pumping out, splashing on the marble floor. The flow diminished, and the body collapsed sideways.

In the dark silence, Quietus spoke. 'With treachery all around me, only misfortune has remained faithful to me – misfortune, my doomed family and my Emesene friend Sampsigeramus.' He ruffled the priest-king's hair, and relapsed into silent introspection.

'Dominus?' Eventually it was Rutilus who dared try to break into the emperor's thoughts.

Quietus continued to stare at the decapitated corpse. 'Afterwards, one always regrets having been so benevolent.' He spoke more to himself than anyone else.

'Dominus?'

Quietus came back from his private world of sanguinary regrets. He snapped out orders. 'Get that thing out of here. We have news that Odenathus is marching against us. It matters little in the long run. Pomponius Bassus will soon appear at his rear. But until then we must take thought for our safety. I am advised I need officers experienced in siege works. The barbarian Ballista is reappointed as Praetorian co-prefect. His colleague Rutilus will command the west and north walls, the Prefect of Cavalry Castricius the east and south. Ballista's will be the overall plan for the defence of Emesa. The barbarian had better do a better job than at Arete. His wife and sons will remain in gaol. As the first Palmyrene is seen on the walls, they will die.'

The Tower of Desolation of Emesa was more an observation post than a defensive work. Its circular battlements were only a few paces across. Its interior was entirely taken up with the twisting stone staircase. The tall tower looked out south-east: five miles of cultivated land, then the measureless high desert, stone-strewn, baked by the sun, infinitely harsh. That might account for its name.

Ballista leant on one of the crenellations and embraced the rare moment of solitude. Up here, the wind tugged at his cloak, made his long fair hair stream away. Out in the desert, he could see it raising tall, spinning dust devils. The wind was from the south. It was going to raise a fierce storm. Odenathus's main army was approaching through the desert from the east. When the storm reached them, they would hunker down, backs to the wind, cloths tied across the faces of men and animals – wait for it to blow itself out. It would delay them by a day or so.

Once, when the Persians sent an army across the Libyan desert to despoil the holy oracle of Zeus Ammon at the oasis of Siwah, a huge storm got up one night. As the soldiers slept, the sand buried them alive. The army was lost for ever. Ballista smiled – no chance of that here. This was a different desert: not enough sand, all too many rocks. Then again, the gods loved Siwah; it was unlikely they had a great affection for Quietus. The army of Odenathus would be delayed by a day or so.

The Palmyrene outriders were already here. Ballista had watched the light cavalry arrive. First, dense clouds of them, clothes flashing bright in the sun. They came in five groups. Each had ridden with purpose to its station. The four main roads – north to Apamea, south to Laodicea ad Libanum, east to Palmyra, and north-east to the distant Euphrates – were blocked. The fifth group spread out to westward, along the banks of the Orontes, watching for any attempt at intervention across the Libanus mountains from the old legionary base at Raphanaea.

The light horse in the second wave that encircled the town were in smaller units. Ballista had watched them swooping through the farmsteads and suburban villas. They were looting – when did soldiers not? – but there was no burning. Their discipline was good. Odenathus did not want to alienate the Emesenes. He wanted them to come over.

Not all the horsemen were Palmyrenes. Through the swirling dust, standards and shield patterns marked out regular Roman units. These alae, originally raised in distant Thrace, Dalmatia and Gaul, must have been provided by governors opposed to Quietus: Aurelius Dasius of Mesopotamia, Virius Lupus of Arabia, and maybe, if the rumours were true, Pomponius Bassus of Cappadocia. These Roman regular light horse came close to the walls, displaying themselves to the Roman defenders. Odenathus clearly wanted them to come over as well.

Ballista was impressed. It was like a hunting expedition on a huge scale. The fixed stakes were driven in, then the nets hung from one to the next, leaving no way out. Odenathus knew what he was about. No need for surprise there. No one harried Shapur out of northern Mesopotamia, retook cities like Carrhae and Nisibis from the Sassanids, unless he knew what he was about.

Numbers of light horsemen were always difficult to judge, but there looked to be about ten thousand of them ringing the town. The Palmyrene heavy cavalry and the infantry were still on the road. Ballista had no idea how many they were. Cornelius Macer – the cousin Quietus had made, among other things, head of the frumentarii – had produced no reliable figures whatsoever. The ineptitude was not enough to make Ballista wish Censorinus back as Princeps Peregrinorum. At a guess, it was unlikely the main body of Odenathus's army was smaller than the force already outside Emesa. So, the Lion of the Sun would have at least twenty thousand men, maybe more, maybe many more.

And to oppose him, Ballista had what? Quietus had a Praetorian Guard of a thousand. There was the core of Legio III Gallica, the main unit of the garrison of Syria Phoenice, some two thousand men. There were also vexillationes of five hundred men each from five other legions: IIII Scythica and XVI Flavia Firma from Syria Coele, X Fretensis and VI Ferrata from Syria Palestina, and III Felix from the outpost of Circesium. The five and a half thousand Praetorians and legionaries were augmented by about the same number of regular auxiliaries. Then Sampsigeramus claimed to have ten thousand Emesene bowmen, horse and foot.

It was a sizeable force: twenty-one thousand men, more than half of them Roman professionals. Unfortunately, it only existed in the mind of Quietus and, seemingly, those of his closest advisors, his cousin Macer and the king Sampsigeramus. In consilium, all the other officers – including Rutilus, Castricius and Ballista himself – paid lip service to it. But in the unobservable places of their hearts, they knew it was not true.

Ten years of wars, foreign and civil, since the coming of the time of troubles had worn the Roman units down. In a decade of confusion, detachments had been sent away and never returned, new recruits had not been levied. Death and injury, disease and desertion had left the units pale shadows of their former selves. Keeping old men with the standards far beyond their time for retirement had caused resentment but done little to maintain numbers. It was dubious if any unit, apart from the Praetorian Guard, had half the men it was said to have. And no one put any faith in the existence of the ten thousand Emesene warriors claimed by Sampsigeramus.

Numbers continued to fall. Desertions continued. Day by day, furtive figures slipped out of the postern gates or over the wall and away. Far from stemming the flow, the arrival of the enemy cavalry increased it. The Palmyrenes welcomed the deserters with open arms.

It was not just the rank and file who were abandoning the regime of Quietus. The sometime Praetorian Prefect Maeonius Astyanax had never returned from his embassy to Palmyra. Astyanax, the great amicus of Quietus's father, now was said to ride close to the right hand of the Lion of the Sun.

Then there was the governor of Cappadocia, Pomponius Bassus, the man who was meant to raise a great barbarian army of Iberians, Albanians, Alani to sweep down the Euphrates and save the day. For some time, no message had come from him. Now it was almost certain he had gone over to Gallienus.

It was surely a sign that even Theodorus, the elderly, hesitant governor of unarmed Cyprus, had sent messengers west openly repudiating Quietus.

A more visible proof yet was Fabius Labeo. Two nights earlier, the governor of Syria Coele had been apprehended inconspicuously leaving by the Apamea Gate. Few senators were much good at being inconspicuous. The two silver-mounted carriages and three wagons necessary to move his essentials and maintain the governor's dignitas had rather taken the clandestine edge off Labeo's movements. With tears running down his face, he had maintained he had been leaving to levy troops in his provincial capital of Antioch. Even Quietus had not believed it. Fabius Labeo now resided in a metal cage hanging over the Apamea Gate. No one was to give him food or water, on pain of joining him. It was generally agreed that the punishment, if novel and possibly un-Roman, did show a certain poetic justice.

'Ready, Dominus?' The Praetorian's head popped up through the trapdoor.

Down below, Rutilus and Castricius were waiting. It was the appointed time to make their daily report to Quietus. Three senior centurions from the Praetorians, including Jucundus, fell in behind as they set off across town for the palace. Apart from occasional trips to the temple of Elagabalus, Quietus never left the palace now.

The officers did not talk as they marched. As soldiers did, Castricius twirled the end of his belt. The metal fitting at the tip thrummed through the air. It was good that he was here. Ballista would have liked to talk to him, but not in front of the centurions, any one of whom, even Jucundus, could be an informer. And there was Rutilus – a good officer, but he had never given any sign he was other than completely loyal to the house of Macrianus.

At the gates of the palace, the Roman officers were brought up short. There was not a single Praetorian to be seen. On duty instead was the royal guard of Sampsigeramus. They could not have formed a greater contrast to the Romans in their plain white un-dress tunics and dark trousers. The Emesenes owned a lack of uniformity that was magnificent and colourful – saffron, blinding white, delicate rose; embroidered with flowers, striped and hemmed. Some had put down their spiked helmets and inlaid shields. Most leant back against the walls, a few with their eyes shut against the glare. Off to the right, a couple had gone further. They sat, heads drooping, with their arms around their drawn-up knees.

Not all were so somnambulant. Their commander may have eased his feet out of his sandals, but his eyes were watchful. He admitted the Roman officers with pursed, contemptuous lips.

They went down one long, cool corridor after another. Now and then, windows opened on to well-watered, shady gardens where caged birds sang. It was hard to believe that the vanguard of the besieging army was not a mile from this profound peace.

A final corridor, and they were at the door of the women's rooms. The guards here had taken lethargy further. A scatter of slippers. Five pairs of naked feet. The warriors lay on a richly patterned carpet. The bottom step of a flight of three served as their pillow. At the top, their leader reclined against a doubled-over cushion. He spoke in Aramaic. One of his men got up and drifted through the door.

Awake, but supine, the guards regarded the Romans with insolent eyes. Behind the easterners, the door was opened. The Emesenes rose to their feet. Their gorgeous silks and languid movements suggested something of the inhabitants of the women's quarters. They followed the Romans up the steps and through the door.

The inside of the women's quarters of the palace of the king of Emesa would have confirmed every prejudice against the Orient of every stern Roman moralist of old. Cincinnatus would have fled back to his plough. Cato the Censor would have had apoplexy.

The room was bathed in a lurid red light. There was an almost overpowering smell of perfume and wine. The emperor Quietus lay on a couch. The priest-king reclined against his chest. Both men were half naked. Quietus absent-mindedly toyed with Sampsigeramus's hair. On another couch, the emperor's cousin Macer lay on his back unconscious. An equally comatose girl lay across him.

In the gloom at the rear of the room was an enormous bed. Girls moved in the shadows behind it. Four more slept on it. They were naked apart from the odd wisp of material, limbs sprawled in abandonment. Another girl had collapsed and lay with the crushed flowers and spilt wine on the floor.

Ballista started to make the daily report. It was a carefully worded thing, keeping to the official line and troop numbers. Even so, Quietus clearly was not interested. He quickly interrupted.

'It is written in the stars that this is a turning point for us. The gods turn their anger on the camel herder of Palmyra. The storm howls around Odenathus's impious ears.'

Ballista broke the ensuing silence. 'Dominus, the storm is unlikely to delay the Palmyrenes for long, not more than a day.'

'They say Odenathus has a beautiful wife.' Quietus's voice was reflective. 'I will enjoy her when he is defeated.'

Sampsigeramus giggled knowingly.

Rutilus spoke. 'Dominus, Odenathus will be here by dusk tomorrow.'

Quietus ignored him.

'We will form a new legion.' Suddenly the emperor sat up, full of manic energy. 'Legio XXXI Macriana Victrix. Its symbol will be the symbol of my family, the image of Alexander the Great. My father always said that those who wear the likeness of the Macedonian are aided in all they do. It will be the same with the legion. After its first victory, we will add the title "Invictus". Rutilus, conscript men from Emesa, and make up the numbers with drafts from the existing legions.'

'We will do what is ordered, and at every command we will be ready,' said Rutilus.

Quietus looked momentarily downcast. 'Treachery all around me. Maeonius Astyanax – my father trusted him. Now Pomponius Bassus – he will lead no army down the Euphrates.'

With no warning, the emperor brightened. 'But it is of no account, none at all. My Princeps Peregrinorum has arranged everything.' He looked over to where Macer lay, stunned by alcohol. The emperor laughed fondly. 'Before he took his deserved rest – otium must always follow negotium, it is the ancestral Roman way – my beloved cousin sent envoys bearing princely gifts to the leader of the Arab confederation of the deep desert. Jadhima of the Tanukh will ride at the head of his horde. The Arabs will fall on Odenathus, scatter his army like chaff on the threshing floor.'

The news was received in silence. The officers tried not to give away their feelings. The idea that any confederation of Arabs could ever come out of the desert and defeat a regular army in open battle was too ridiculous for words.

Rutilus tried again. 'Dominus, our scouts say the storm will blow out quickly. Odenathus will be here by dusk tomorrow.'

'Tomorrow, the day after, it makes no difference.' Quietus waved a hand at Ballista. 'The night he arrives, you will lead a raid into the heart of his camp. If you cannot bring him to me alive, you will bring me his head. It will be finished.'

'We will do what is ordered, and at every command we will be ready.'

And Odenathus will be ready too, thought Ballista. Now a collection of Emesene guards and palace girls know of the plan. Odenathus knew what he was about. He would have spies in the palace.

'By the next dawn, the Lion of the Sun will be dead,' Quietus added softly, 'or others will suffer.' Night and not enough darkness. The flames of the torches sawed in the wind. The orange glow illuminated the inside of the Palmyra Gate. Only at the very top of the tall arch night still held sway. Lower down, the sculptures of the eagle, altar and conical stone of Elagabalus were thrown into shifting heavy relief. Below them, the palimpsest of graffiti – thanks to the god for safe arrivals or pleas for help getting across the desert unharmed – was almost legible.

Night and far too much noise. The five hundred or so Praetorians gathering for the raid stamped their feet against the chill breeze, or just out of boredom. The unbound hobnails of their boots rang on the paving stones. There was a continual jingle and chink of equipment; several thousand metallic awards for valour, and good-luck charms hung on their harnesses. There was a low buzz of talk. One or two groups were passing around wine-skins.

Disciplina was not good in the army of Quietus. But there was a deeper reason for the men's behaviour. The Praetorians had been seconded from the eastern legions, and they had a reputation among officers for lack of disciplina. How could it be otherwise? Their camps were not in bleak frontier fastnesses like Caledonia or Germania but near comfortable towns. Sometimes they were even billeted in the towns themselves. And the towns were eastern. Most of the men had been recruited locally. At bottom, they were easterners, with all that implied about insolence and loose living.

No one had told the Praetorians to bind rags round their hobnails, to take off their charms. No one had ordered them to stop talking or drinking. There was no absolute certainty of being obeyed. Ask any legionary or auxiliary out on the frontier – the Praetorians were overpaid, arrogant and pampered; all plumes and sashes; parade-ground soldiers, useless in a fight.

Ignoring the commotion, Ballista leant against the wall. He pulled an old black cloak around himself and shut his eyes. The usual smell of Roman soldiers: unwashed men, with undernotes of garlic, cheap perfume and sour wine. Once – when the centurion and his men had come to the hall of his father – it had been alien and frightening. Now – twenty-three winters later – it was homely and reassuring. Like everything else we think innate, the evocations of smell are often shaped by circumstances outside our control.

Ballista found himself thinking about Turpio. His old friend had boasted of a particularly keen sense of smell. Ballista wondered what scents had come to Turpio five years earlier as he had waited under another gate to Palmyra, the one at Arete, to lead a mission with a different target but the same aim. Turpio had so nearly taken the Persian King of Kings unaware in his tent. But he had not. All he had taken was a golden bracelet. And years later, it had proved his death. For mortals, mortal things. And all things leave us. Or if they do not, then we leave them.

The lines ran through Ballista's mind. Turpio had been fond of modern poetry, but Ballista had no intention of letting this nocturnal raid be the death of him.

'Have a rest, you poor little thing.' Calgacus puffed up and put down the two lanterns he was carrying. 'After tonight, we may have all fucking eternity to rest.'

Somewhere in the town, dogs were barking. In Aeneas Tacticus's book on defending a town under siege, the general was advised that, to avoid noise and confusion, all dogs, strays and otherwise, should be rounded up and killed. Ballista had read the book at least twice. In this town, he had not acted on that piece of advice.

'Here comes Jucundus,' said Calgacus.

Ballista opened his eyes.

Jucundus marched up and saluted. The noise from the Praetorians had dropped appreciably with his arrival. Jucundus was solid dependability personified. He reported his men ready; a column five wide and a hundred deep to pass through the gate; once outside, they would redeploy ten wide.

Ballista thanked him. They waited for Castricius.

The sometime convict now Prefect of Cavalry came down the steps from the artillery platform two at a time. The stone-thrower and the two bolt-throwers were ready. Ballista thanked him.

The northerner drew Jucundus close to quietly explain the stratagem, for should Ballista fall, Jucundus must carry it out. The artillery pieces were drawn back but unloaded. At night you could seldom see the missiles fly. If the raid got into trouble, these two blue lanterns should be hoisted. Castricius would release the artillery – they sound the same whether they are loaded or not. With luck, Odenathus's men would think they were being shot at – there is little more frightening than incoming missiles you cannot see – and retreat out of range. It had worked before with the Persians at the siege of Arete. The gods willing, it would work again now.

'We will do what is ordered, and at every command we will be ready.' The two officers went to withdraw. Ballista indicated Castricius to remain. The northerner talked so that only Castricius could hear. The latter listened intently, the flaring torches scouring deeper the many lines on his face, highlighting its points and sharp angles. The talk was obviously of serious matters, but in the flickering light Castricius never looked more like a playful creature from a backwoods myth.

It was time to see if the raid could go ahead at all. Castricius clattered back up the stone steps. Ballista asked one of the legionaries on the gate – they were from III Felix – to open the postern. Following Calgacus through, he noticed it was big enough for someone to lead a horse.

The postern shut behind them. The rectangle of orange light vanished. Ballista was left in profound darkness. He stood still, waiting for his night vision. Beside him, Calgacus hawked and spat.

The nearly full moon was somewhere over Ballista's right shoulder. He stood in the deep shadow of the town walls. Beyond was the moon-blanched landscape. He went out into it. Calgacus followed.

The road ran away, very light, smooth and straight. Near at hand, on either side, prominent and reassuring to Romans of rank with a clear conscience, stood the symbols of the divinely inspired power which upheld the stability of the imperium. The crosses were empty, but there was a dark stain at the base of the one to the left. Ballista did not like to wonder what fluids were its cause. Maybe the local dogs pissed there.

The shadow of the right-hand cross pointed diagonally off down the road. The eastern necropolis of Emesa was like a reduced version of those outside Palmyra; the same tower, temple and house tombs, but most of them on a somewhat smaller scale. The houses of the dead were close-set. The ground between them was rough and stony. It would make it difficult to outflank the raiding party on the road. At least that was something good.

Little else was good. The necropolis ran for about two hundred yards. About the same distance further out were the picket fires of the Palmyrene army. They burned rose-red, were well made up, evenly spaced. Beyond them, yet another couple of hundred yards, were the bigger fires of another picket line around the main camp. These too looked well tended. There were Roman regulars among the blockading army. Vexillationes of at least three legions had been seen: III Cyrenaica from Arabia, XV Apollinaris from Cappadocia and, mirroring the detachment in Quietus's force, III Felix from Circesium. Yet Ballista considered that the Palmyrenes needed no guides in the craft of war – they knew what they were about.

As for Odenathus, he not only knew what he was about, nature was aiding him too. The moon, like some radical democrat in old Athens, wanted everything out in the open and treated all the same. It was bright as day but without the colours. The world was snow-blue or black. Anything that did not stay in the shadows was visible for miles.

As if the gods wanted to reiterate the point, a fox came out from behind one of the furthermost tombs. Ballista watched it cross the road. Its high ears and low body were strangely one-dimensional; its shadow had an unreal depth. But tricks of the moonlight aside, it was easy to see.

A single fox at a couple of hundred yards – what price five hundred men at twice the distance? This was hopeless. If pressed home, suicidal.

Ballista walked back to the postern and kicked it to signal that the operation should get under way.

The Palmyra Gate had not been oiled. The shriek of its hinges rushed away across the plain. Not all the torches had been extinguished. The Praetorians were orange-tinged silhouettes as they emerged. The gate shrieked shut behind them. The soldiers jingled and thumped into their new formation.

As if Odenathus did not know we were coming anyway, Ballista thought. Calgacus at his side, he took his place with Jucundus at the head of the column. Ballista ordered the standard bearer Gratius to signal the advance. Best get it over.

In the forsaken, luminous light, their shadows went on far ahead. The shadows ran on as if the men's souls had already left and were flitting away, searching for some fissure to slide down to Hades.

Ballista could hear nothing over the heavy tramp of boots and the higher notes of harness and weapons, like ten thousand bone dice clinking together. He could see no movement from the nearer picket fires. Even if not forewarned, the Palmyrenes must have heard or seen them coming. He knew they were walking into an ambush.

They were clear of the last of the necropolis. The land opened up all around, flat and deadly. Two hundred yards to go. No movement by the fires. Come on, come on. Get on with it. One hundred and fifty. They were within bowshot. In the darkness beyond the fires, the Palmyrene archers would be notching arrows, waiting for them to walk into a good, effective range – the range where the tip of an arrow can punch through the best steel armour and into the delicate flesh it covers.

Twang-slide-thump. From the wall behind them, loud in the night, the sound of an artillery piece. The lanterns were still shuttered in Calgacus's hands. Twang-slide-thump: the sound of another. Now there could be no question of surprise.

'Halt!' Even as Ballista's voice faded, a trumpet called from beyond the fires. Seconds later, no one in the column could help but duck as they heard the whoosh of arrows.

There was only one scream. The first flight had almost all fallen short.

'About turn. Quick march.' The Praetorians jostled to obey.

Again the horrible sound of unseen arrows. Again just a solitary yell of pain. The second volley had also been misjudged.

Ballista looked over his shoulder. He saw his own shadow, elongated into the distance. It was the moonlight. In the uncanny light, distances were hard to judge.

A terrible, huge, tearing sound. Screams behind them. Castricius had decided the time had come for his artillery to use missiles. All along the wall, from tower to tower, echoed the sounds of torsion artillery. They were shooting virtually blind into the night; aiming roughly at the picket fires. Yet it should be enough to deter any close pursuit.

'Run!' Ballista shouted.

The gate banged shut behind them. The orange torchlight could not have been more welcoming. They had not returned unscathed. The ever-efficient Jucundus reckoned ten men missing. It could have all been so very much worse.

The palace of Emesa, like that of Minos, was a maze. Of course, the Emesene priest-kings had had over three centuries to add architectural complexity. There had been a Sampsigeramus waiting all those years earlier when Pompey the Great had first led Roman arms into Syria.

Even if they had just been given instructions, it would be doubtful if Ballista, Castricius and Jucundus would have found their way to this secluded courtyard on their own. The morning after the failed raid, this had not been put to the test. Summoned in haste, they had arrived at the main gate and had been taken in charge by no less than sixteen of the Emesene royal guard. As Jucundus had muttered, the odds were worse than five to one.

Since the time of the first emperor, the Praetorians had been among the few who were allowed to be armed in the imperial presence. The more recent post of Prefect of Cavalry was one of the others. None of this held any longer at the court of Quietus. The Emesene guards had brusquely disarmed and thoroughly searched Ballista and the other two. Their weapons and armour were piled negligently against the wall. The easterners, uncaring of their wounded foreign dignitas, had hustled them like condemned prisoners through the myriad corridors of the palace.

Like the palace of Minos, at the heart of the maze was something unpleasant. Quietus at first completely ignored the new arrivals. The emperor was dressed in eastern fashion: long, flowing robes, a jewelled dagger in his sash. Arm in arm with Sampsigeramus, he wandered here and there across the courtyard. Quietus inspected things, issued commands and reproofs, even the occasional word of encouragement.

The open space was a hive of activity. At one end, slaves were laying out a huge array of precious things: paintings, sculptures, dinner services in gold, silver and electrum, intricate carpets and curtains, silken garments. Quietus studied them closely, head on one side, rearranging his hair with one finger. Sometimes he ordered an item removed and another brought out in its place. Opposite all this, other slaves were building an elaborate pyre, surely too close to the wall; with the amount of scented oils being poured, it would burn with an all-consuming ferocity.

Ballista had seen nothing like it before, but it was all oddly familiar.

There was an awning strung over the whole courtyard. It was torn near the centre and let in a column of clean light. The slaves walked tentatively around it, as if it were solid. The emperor and his friend avoided it as if it could hurt.

Despite the shade, it was hot. Soon Quietus and his delicate eastern priest-king needed a rest. At a word, work was suspended. A couch was brought out and they reclined between the mountain of luxuries and the half-built pyre. They sipped drinks chilled with the snow of Mount Libanus.

Ballista stood rigid. Castricius and Jucundus did the same. They were unarmed, ringed by guards, prey to justified fears. Quietus's words at their last meeting ran round and round in Ballista's thoughts: by dawn, the Lion of the Sun would be dead, or others would suffer. The northerner pictured the senator Astyrius in the gloom of the temple; his headless trunk in the pooling blood. Rather that happen to himself, here and now in this sweltering courtyard, than any harm come to his boys. Let this be over. It was the waiting that always threatened to unman you. Calm, calm. In a way, what was life but one long wait for the final, horrible thing?

At long last, Quietus waved a long-sleeved arm to summon them over. They got up from proskynesis. The sand of the yard had been watered to keep the dust down. It fell in crumbling lumps from the front of their tunics.

Quietus gestured, palm limply up, at a painting. Ballista recognized it as the one from the consilium in the palace at Antioch: The Wedding of Alexander by Aetion.

'What do you think it means?' Quietus asked.

The three officers may have had views, but they kept quiet.

'My dear Sampsigeramus thinks it shows how love and sex can make even the most warlike men, such as the great conqueror, forget the battlefield and soften their bellicose natures.'

Quietus gently ran his hand through Sampsigeramus's hair. 'My dear boy is too trusting. Look what those cupids are doing. Some of them distract Alexander by pulling the clothes off Roxanne. The others drag away his weapons out of reach. All the while, two men stand behind him, another peers around the door. Treachery – it is nothing but an allegory of treachery.'

The awning snapped in the silence.

'Nothing has been spared me,' Quietus complained. 'No disappointment, no treachery, no dishonour, no betrayal. Maeonius Astyanax, Pomponius Bassus, even that weak old fool Theodorus – all traitors. At least Fabius Labeo is discovering the ultimate wages of treachery.'

Quietus suddenly spread his hands wide, palms up. 'And where is the Lion of the Sun this morning? Is he grovelling in the dirt at my feet? Instead, the three of you stand here. Tell me, why did last night's raid end in ignominious failure? What was it if not yet more treachery?'

'No, Dominus.' Ballista was surprised how resolute his voice sounded. 'The Palmyrenes were vigilant. Our men were ill-disciplined. It was bad luck. No treachery.'

'That cannot be.' Quietus was adamant. 'Someone must be held accountable, or the world may think this failure reflects on our own majesty. Our maiestas must be sacrosanct.' His gaze flicked feverishly over the three officers. 'And one of you has already shown himself a traitor.'

The three men stood very still. More Emesene guards appeared from the corners of the yard. The officers were surrounded. There was nothing languid about these easterners. There was the slither of swords being drawn. The Romans stood empty-handed.

Ballista measured the distance to the imperial couch. Five, six paces. A ring of armed guards in the way. He had no weapon. Try to shoulder through, take the wounds. Get to the couch. Grab the ornamental dagger on the emperor's belt. Use it to kill Quietus. Hold the blade to Sampsigeramus's throat. The guards were his men. Bargain for a safe passage.

It was hopeless. Ballista knew he would not get two steps.

'Nothing spared… no betrayal,' Quietus said softly.

The three officers were rigid, waiting.

Quietus thrust out a finger at Jucundus. 'You' – his voice was low – 'you have been comforting my enemies. My enemy's friend is my enemy.'

The centurion knew his life hung on what he said. 'Dominus, I have done no such thing. A malicious informer must have made a false accusation.'

Quietus, quiet as an owl, looked at him.

'Dominus.' The strain showed in Jucundus's voice. 'Dominus, the delator must be in the pay of Odenathus – trying to remove your loyal officers.'

'Not at all,' said Quietus. 'What you did is widely known. You have not even made a secret of it.'

Jucundus was silent.

'You cannot deny taking all manner of comforts into the prison for Ballista.' Quietus smirked like a man who has made a winning throw at dice.

Ballista reacted first. 'But, Dominus,' he exclaimed, 'I am not your enemy. I am one of your Praetorian Prefects. You have entrusted me with the defence of the city.'

'All true now,' Quietus shouted, 'but not true then. Then I thought you were my enemy – that is enough. Jucundus openly succoured a traitor, threatened the gaoler that he better treat the traitor well, betrayed all my trust.' Quietus was almost screaming; flecks of spittle flew from his lips. 'What price loyalty when my wishes are openly mocked?'

Ballista persevered. 'You trust me to command Emesa. Jucundus is one of my most trusted officers.'

'You boast of your loyalty? Well, prove it now. Take a sword and execute the traitor Jucundus.'

A guard stood forward, reversed his sword, held the hilt out towards the Romans.

Ballista did not move.

'Cut him down, or you will die with him.'

A rasp of steel. Quick as a snake, Jucundus had the sword in hand. Its owner leapt back.

The Emesene guards crouched, ready to fight, just waiting for a move or a word of command.

Jucundus changed his grip, thrust the tip of the blade up under his breastbone.

'I will die like a man, not for your amusement.' Jucundus's eyes did not leave Quietus. 'You will die worse. I pray to the gods to be avenged.'

Jucundus threw himself forward. The hilt hit the sand. The blade tore up into his innards. He writhed sideways, groaning in agony.

Ballista found himself on his knees by Jucundus. 'Finish it,' the dying man whispered. Ballista prised the hands loose from the hilt. He twisted the blade, withdrew it, thrust again. Jucundus sighed a great sigh and died.

Ballista got to his feet. The knees of his trousers were soaked in blood. The reeking sword was still in his hand.

The guards hefted their weapons.

Ballista dropped the sword. It thudded on to the stained, fouled sand.

'For I too am dust…,' Quietus mused. 'Life does not forgive weakness… You two return to your duties.'

They recovered their weapons and armour. They left Jucundus's where they lay. Outside, they shouldered the general guilt of the survivor and their own sharper, more specific, individual guilts. They walked. Briefly, they were alone. Ballista put his arm around Castricius's shoulder and talked low and fast into his ear. Castricius turned off to his headquarters above the Palmyra Gate. Ballista walked on to the Tower of Desolation. He climbed the winding staircase. There were six Praetorians on lookout, about all the fighting top could comfortably hold. Ballista told one of them to go and get Calgacus; the freedman was to bring his patronus a papyrus roll, ink and stylus as well as his best, favourite black cloak. Ballista leant forward, settled his elbows on the low parapet and waited.

When Calgacus appeared, Ballista dismissed all the Praetorians.

'Quietus killed Jucundus.' There was no need for preamble.

'I heard.'

'Of the three of us, he was the innocent one. He was gone when I told Castricius to make sure one of the artillery pieces was released early.'

'I know it. But there is nothing to be done about it now.'

'Quietus is building a pyre in the palace.'

'Many men will kill themselves rather than be taken alive – the Romans make a cult of it.' Calgacus shrugged. 'Sooner the fucker is on it the better.'

'It is not just himself he intends to kill,' said Ballista.

Calgacus pursed his lips.

'There was a king of Assyria called Sardanapallus,' said Ballista. 'He was besieged for two years in his capital, Nineveh. When there was no hope, he had every precious thing he owned and everything he had enjoyed collected together. The women and boys he had fucked, all the horses he had ridden – their throats were cut. The bodies and the treasures were burned with him.'

Still Calgacus said nothing.

'Quietus is heaping up his things by the pyre. I think he intends to play the Assyrian. He wants his passing to be marked by an orgy of destruction. He will take many others with him. Quietus is insane.'

'Aye, most likely,' said Calgacus. 'So you have to play the hero again.'

'I am going to fulfil a vow I made some time ago,' Ballista said seriously. Then he laughed. 'And you get to play the hero too.'

'Fucking wonderful,' Calgacus said, without expression.

'Get two quiet horses and some drab clothes. Keep an eye on this tower. When you see me wave this best black cloak from the battlements here, go to the prison. Kill the gaoler and any of his assistants – there is seldom more than one – they do not look like fighters. Ride with the boys and Julia to the Palmyra Gate. Castricius is expecting you. He will let you out through the postern gate. Take them to Haddudad and Odenathus.'

'And you?'

'I am going to play on Quietus's obsession with treachery to get him to come here.'

'And then?'

'Cheer up, sooner or later he will probably kill us all anyway.' Ballista looked out from the Tower of Desolation at the desert and the sown. The strip of tilled land was full of Odenathus's army. In the desert was nothingness, desert absolute.

If you were dressed in just a tunic, with the breeze, it was almost cool up here. Calgacus had helped him strip off his equipment. Though they had done it before, it was hard saying goodbye to the old Caledonian, very hard. Nearly a lifetime of largely unspoken affection. Calgacus had asked him would he not go and see his boys. Ballista would not. He had not the courage for it. Tell them he loved them. Tell her too.

The old man had left without a word of complaint.

Up on the tower, Ballista had waited. Calgacus needed time to collect the horses and clothes. The sun had crawled across the sky. Eventually, Ballista had summoned a Praetorian to go to Quietus with a message.

Before he left, Calgacus had handed over the things. The best black cloak lay at Ballista's feet. The writing things were in his hands. He must write something. A letter to his boys and wife? Depending on how things fell out, it might be twisted and used against them. He wrote, 'Legio III Felix'. Then he tore from the roll the thin strip of papyrus with the words and twined it round his fingers.

Ballista, stylus in one hand, scrap of papyrus in the other, leant on the crenellations and tried to calm his thoughts. The Norns had spun his fate. The length of his life and the day of his death had been fated long ago. Nothing he could do would unpick it.

His mind was not stilled. Too many questions were running through it, treading hard on each other's heels. Would Quietus come? Most likely – he was baited with treachery, and he was mad for treachery. Had Maximus reached Palmyra? Had Haddudad taken him to Odenathus? Had the Lion of the Sun believed Ballista's letter? Was Maximus out there watching this very tower from somewhere in the camp now? There was no telling for any of it. Would Calgacus save his boys and Julia? About this, the most important question, he felt oddly calm. He had no doubt that Calgacus could deal with the gaoler and his assistants. Of course Castricius would see them safe through the postern gate. Haddudad owed Ballista's family every hospitality. He almost smiled at the thought of Julia and Bathshiba together. But then, what of himself – would he succeed or fail?

And when it was done or not, what then? Was there an afterlife? The Christians seemed certain. It buoyed them up in the face of the steel and fire. Ballista had seen the insane resolve it gave them. But it made no sense to him. The resurrection of the body – what a nonsense. Why would you want to come back old and infirm, wracked with the pain of the thing that killed you? And if you had a choice, how could it work? You wanted to be thirty. You wanted to be with the twenty-year-old woman you loved then. But your sons were not born then, and you wanted to be with them too. As for the woman, maybe she had a better time of it with someone else. It would be an accommodating god that would give each Christian their own heaven.

Ballista's ancestral Valhalla seemed a far better choice: the slick-palmed excitement of battle every day. You took the pain, but then wounds miraculously healed, there was a feast every night – food, drink, poetry, the friendship of men, and later, as the stars wheeled across the bottomless sky, the love of women. But even here, problems crept in, like the Evil One. In Ballista's childhood, there had been no mention of books in the hall of the Allfather. But now, without reading, it would be a barren existence for him. And his boys – there could be no certainty they would join him. And being without them would be far worse than losing all the books in the world. Twenty-three winters in the imperium had changed him. The boys had changed him.

Ballista felt hungry. He called down for a Praetorian to bring him some bread and cheese, some ham as well. After the soldier had gone, he realized ham might be difficult in a town where the natives appeared not to eat pork. Still, Roman soldiers had never been renowned for their sensitivities to other cultures.

No sooner had the food arrived, ham and all, than the cavalcade of Quietus appeared in the street below. The emperor was dressed in eastern costume and attended by twenty gorgeously caparisoned Emesene cavalrymen.

Ballista was eating when the Praetorian brought a couple of the local troopers up. The latter searched the northerner with as much impertinence as they could muster. They took away his food, fingered his cloak and writing materials suspiciously, and peered around the minuscule fighting area for anywhere a concealed weapon might lurk. When satisfied, one of them went back down the stairs. Neither the other nor the Praetorian took their eyes off Ballista.

It took some time for the emperor to climb to the top of the tower. When he emerged, he was out of breath, leaning on the arm of an easterner. Another Praetorian followed.

There was barely room for Ballista to perform proskynesis.

Quietus shook himself free of the trooper. The four armed men wedged themselves close together at the top of the steps. It gave just a little room to the emperor and his Praetorian Prefect.

'Get up.' Quietus's voice was peevish. 'This had better be true.'

As Ballista got to his feet, he picked up the scrap of papyrus and the stylus. 'It could not be more so, Dominus.' He handed over the curling papyrus.

Quietus unrolled it and read. 'Your messenger said this was shot over the wall tied to an arrow. It is the identity of the unit that wishes to come over to us.'

'The first unit that wishes to throw itself on your clementia. There will be others,' said Ballista. 'It makes sense that it is Legio III Felix. A vexillatio of the unit is already serving you.'

'And you arranged a signal to confirm this with the archer?'

'I am to wave a black cloak from this tower. If a similar cloak is waved from the siege lines below, Legio III will come into the city by the Palmyrene Gate tonight.'

'Well, what are you waiting for? Get on with it.'

Ballista reached down and gathered the cloak in his left hand. He lifted it high above his head. Making quite sure it could be seen from inside as well as outside the city, he waved it vigorously.

'From where in their lines will they answer?' Quietus was leaning on the parapet, gazing out.

'I do not know, Dominus.' Ballista put the cloak down. 'We must watch and wait.'

'There! There it is!' Quietus was pointing, all his attention on the enemy outside.

Do not think, just act.

Ballista stabbed the stylus into the emperor's neck. Quietus, howling, tried to turn, hands reaching up for the wound. Ballista withdrew the stylus, dropped it. He heard movement behind him. He grabbed the emperor, one hand clutching the embroidered front of Quietus's tunic, the other at his crotch. Blood was flowing down both of them. Ballista hauled him up the battlements, pushed him backwards. Quietus's hands clawed. One locked in Ballista's hair, the other scratched at his face. More violent movements at the stairhead, out of sight. Ballista pushed Quietus out over the crenellations. Only the emperor's legs were still in the tower.

Ballista let go.

Quietus's pouched little eyes were wide in realization and fear, filthy little mouth open in a despairing scream.

Ballista felt pain as a handful of his hair was torn out.

Quietus fell, arms and legs flailing hopelessly as he scraped down the sheer stone wall and on to the hard, unforgiving rocks below.

No noise behind Ballista. He had not been attacked. He turned slowly. He was unarmed. He had even dropped the stylus.

The two Praetorians faced him. Swords drawn.

A pool of blood flowed out from where one of the easterners lay. It began to drip and then run over the top step. The other Emesene was nowhere to be seen.

Ballista looked at the Praetorians. One of them had a distinctive angular face, a huge hooked nose.

The Praetorians looked at each other, then back at Ballista.

As one, they reversed swords, held the hilts out, and shouted.

'Ave Caesar! Ave Imperator Marcus Clodius Ballista Augustus!'

An imperium of three men, one of them the emperor. There had been ten subjects, the whole contubernium stationed at the Tower of Desolation, but Ballista had sent one to each of the six legions, and one each to Castricius and Rutilus. None of them had come back. He was left standing at the base of the tower with Ahala and Malchus, the two Praetorians who had originally hailed him emperor.

Ballista laughed at the improbability of his elevation. An unarmed barbarian. He'd even left the stylus somewhere up on the battlements. A new Augustus with ten followers. Now down to two. It was good that the Emesene cavalrymen had run away when Quietus was killed. But this could still be a very short reign.

There came the sound of running feet. Hobnailed boots, jingling harness. Soldiers, coming fast, and not a few of them. It could be a very short reign indeed.

Ballista saw Ahala and Malchus look at each other. Any misgivings now were futile. Their fate was bound to his like a dog to a cart.

The soldiers came round the corner – from their shields, men of Legio XVI Flavia Firma. There were about forty of them, headed by a centurion. In the reduced circumstances of the army, it was what passed for a century. The legionaries had drawn swords. They were in no doubt where they were headed. They were running purposefully.

'Titus went to them,' said Malchus. 'He is bringing them to us.'

'I do not see him,' said Ahala.

Malchus looked beseechingly at Ahala. The latter shook his angular head. There was nothing to do. The two who first hailed a failed pretender had nowhere to run.

Sunlight flashed on the advancing blades.

The centurion flung up his right hand.

The legionaries halted. Five, six paces away. They were panting. They were tired, but they were ready to kill – they had that wildness about them.

'Dominus.' The centurion saluted. He was not young. The impressive array of awards on his armour rattled as his chest heaved. 'Dominus, Sampsigeramus has declared himself emperor. He has ordered the palace fortified. He is leading troops to sieze the temple of Elagabalus.'

There had been no acclamation, no proskynesis, but the centurion had called Ballista Dominus. As emperor or as prefect? The thing hung in the balance. But clearly he would rather lead his men on the orders of Ballista than the priest-king of Emesa.

'Do you know how many men he has with him, Centurion?' Ballista's voice was calm, competent.

'No idea, Dominus. There has been fighting. Sampsigeramus's men attacked some of those who would not take the sacramentum to him.'

'Does he have Romans as well as Emesenes?'

'We saw some from Legio III Gallica, some auxiliaries as well.'

It was not a huge surprise. Legio III Gallica had been the local legion for a long time. It had supported other pretenders – Heliogabalus, Iotapianus, Uranius Antoninus – from the royal house of Emesa.

'Have any of the Emesene troops refused to acknowledge him?'

'Not that I know, Dominus.'

The Actium trick, thought Ballista, we will have to try that. Octavian, the first Augustus, had declared war not on Mark Antony but on Cleopatra. Turn a civil war into a foreign one. Any Romans on the other side have been so corrupted by decadent foreign ways, just like Antony, they have ceased to count as Romans.

'Men coming, Dominus,' said Ahala.

These soldiers were marching without undue haste. They were from a regular auxiliary unit, Dacian spearmen, about eighty of them. They stopped as one and saluted smartly. With the hope of a donative, they moved as if on a parade ground.

'Ave Imperator Caesar Marcus Clodius Ballista.'

Their centurion introduced himself and announced that imperial regalia must be found: the diadem and purple cloak, the sacred fire, the wreaths of oak and laurel. And lictors, there must be the right number of lictors carrying the fasces.

Ballista thanked him, but said finding him some arms and armour was more pressing. This went down well with all the milites present. Ballista sent a couple of legionaries to Hippothous at the rented house for his equipment, and another one to the Palmyra Gate to talk to Castricius. He had been going to send one to check the gaol when he remembered that Sampsigeramus had fortified the palace.

Now Ballista had about a hundred and twenty men with him. He knew more were prepared to fight Sampsigeramus, were already fighting him. Time for a speech while they got his armour, then off to try the luck of war at the temple of Elagabalus.

'Commilitiones' – Ballista's voice was used to reaching the rear ranks – 'The tryant is dead! I killed him with my bare hands – these hands.' He paused while they cheered. 'I had no thought except to free the army and the Res Publica from his foul actions, the filthy actions that degraded us all. When the soldiers hailed me emperor, I could not have been more surprised. I have no desire for the high office. I would walk away now, but the situation does not allow it. The Res Publica is in deadly danger again. The tyrant may be dead, but his teacher in tyranny – or should we say his husband? – is alive. Sampsigeramus, this cinaedus, this sniggering little easterner, is not only alive, but he has the audacity to claim the purple! These arrogant orientals never learn. We all know what happened to his kinsman Heliogabalus – dragged through the streets by a hook, then stuffed into a sewer.'

'The hook, the hook… drag him, drag him.'

Ballista waved his arm for silence. The chanting stopped as if performed by a well-trained chorus.

'And who supports him? A bunch of easterners like himself.'

The soldiers jeered – no matter where they came from, their primary identity was Roman soldier.

'Wait,' shouted Ballista. 'Do not get overconfident. We have a dangerous fight on our hands. These easterners are tough – they only ever wear the thinnest silks. And they have stamina – they must have to take it up the arse all night.'

The soldiers liked this stuff. Ballista knew it was all bollocks. But the soldiers liked this stuff.

'If you come across any from Legio III Gallica, do not worry. They have been out here so long, they have gone native. They are worse than the natives – taught the locals how to suck cock. Not one of them did not start his life abandoned on a dung heap in a back street of Raphanaea or some such Syrian shithole.'

'Fuck them, fuck them…'

'It is time to go and pull this effeminate off the throne. Sampsigeramus is hiding in the temple of Elagabalus. The god will not help him. We will drag him out and kill him.'

'Drag him, drag him… the hook, the hook.'

'Remember the temple is sacrosanct. Any soldier pillaging it will suffer the harshest penalty. But the palace is not. After we have dealt with Sampsigeramus, shall we see what we can find there?'

'Dives miles, dives miles.'

'After I have had a look at his treasury – all the wealth taken by the avarice of Quietus's father – a donative to the loyal troops will be announced.'

'Rich soldier, rich soldier.'

Hippothous and some other men had appeared with Ballista's weapons and armour, his original bird-crested helmet. They helped him into it. There was still no word from Castricius about his sons and Julia, but he had to put them from his mind.

The troops fell in, and they set off.

On the way across town, their force was augmented by a complete ala of Dalmatian cavalrymen. They had come straight from their barracks. They had left their horses behind as unsuitable for urban fighting. They were lightly armoured and there were only about two hundred and fifty of them but, to Ballista's tiny force, they were a hugely welcome addition. The great temple of Elagabalus was set in a walled precinct, however, no attempt had been made to defend the outer walls. The main gates stood untended and open.

Perhaps Sampsigeramus did not have all that many men with him. He would have left a substantial number to hold his palace. Presumably more Emesene warriors would still be at their stations on the city walls. Ballista wondered just what Rutilus and Castricius were doing. This would be an opportune moment for Odenathus to attack.

While his men formed up in the street, Ballista peered in through the gates. The temple on its tall podium was in the region of a hundred paces away. Halfway between the gate and the temple was the great altar. Ballista noted that its three fires were still burning. There was no other cover. The sacred grove was off to the left, level with the temple. To the right there was nothing until some service buildings beyond the temple. Something like a hundred Emesene archers were drawn up at the foot of the steps in front of the temple. There were more of them up on the pediment and roof. It was quite possible yet more might be hidden among the conifers of the sacred grove.

Ballista had not yet seen any legionaries from III Gallica, or any Roman regulars at all, but this was going to be far from easy. One hundred paces across an open, arrow-swept yard. Ballista gave the order to attack anyway.

Ballista got ready to go in with the first rank from Legio XVI Flavia Firma. The days when an emperor could keep well to the rear – and keep the respect of his troops – were gone. His old enemy Maximinus Thrax had set the new precedent, charging in at the head of his men. Of course, apart from his strength and skill at arms, Maximinus Thrax had had little to recommend him as emperor. Like another barbarian very recently declared emperor, Ballista thought wryly.

The arrows came screaming at them as they went through the gate. They hunched forward like men advancing into hail. The noise was all-encompassing: arrowheads slicing into wood, metal, leather, flesh; men muttering, praying, shouting, howling. They kept going forward.

Ballista's shield felt as if it were being kicked as arrows slammed into it. Three of the warheads punched through, one only an inch or so from his face. He snapped them off, kept moving. He was sweating hard.

How far? Ballista peeped out around the edge of his shield. Allfather, they were only just coming up to the altar. The weird foreshortening as the arrows sped towards you. He ducked back, blocking out the screams, forcing his legs to keep moving.

A cheer from the men around him. Ballista looked out again. The arrow storm was still there, but less of it, and at a different angle. The archers at the foot of the steps had ceased shooting. They were fighting each other to get back through the doors of the temple. Those up on the pediment and roof still wielded their bows. There were not that many of them. Now Ballista was able to note there were no missiles coming from the sacred grove to his left.

Hefting their shields higher, the soldiers ran forward. The withdrawal of the enemy into the temple seemed to have struck shackles off their legs. They were at the foot of the steps in moments. They set off up them. Hobnails screeching, gouging the marble. The great dark-wood doors at the top slammed shut.

A whistling sound – above the noises of the men – unexplained, eerie. A terrible crash. The men stopped. A stunned silence, then the high screaming of men in agony.

Something made Ballista look up. Sometimes your eyes see something so unexpected your understanding lags behind. Figures falling through the air, turning slowly. Rigid, yet unresisting. Getting faster.

The next statue slammed into the steps a few paces away. Marble into marble. Vicious, jagged fragments flying. The white steps now veined red. Another crashed down. And another. Pandemonium.

Ballista was cowering down. His shield had a wide rent. There was blood on his right leg. The men were running. He looked up at the pediment. Another divinity was teetering on the edge. Ballista ran too.

Back safe behind the outer wall, Ballista called the officers to him and took stock. Not that many casualties. They had left twenty or so inside the precinct; the dead or those too hurt to crawl. About the same number had made it out but were incapacitated by injuries. Ballista ordered they be tended, as far as it was possible, where they were. He could not afford to be without the men needed to take them to doctors.

Ballista questioned those around him on the layout of the temple precinct. It was Ahala, now binding up the flesh wound in Ballista's right thigh, who proved extraordinarily informative. The wall was high all around the compound. There were two other gates. One at the far western end opened next to the service buildings. From there you could get into a low walled yard that butted up to the rear of the temple. There was a wicket gate to the yard and a small back door to the temple. They would almost certainly be defended, and it would be hard to force the narrow back door, but it was worth a look. The other gate was off to the left in the southern wall and led straight into the sacred grove. There was a forester's hut just by it.

'You know the layout well,' said Ballista.

Ahala looked embarrassed. 'When we first came here… some of the boys told me there were sacred prostitutes in the precinct – had to take you on for their god, no matter how low the coin.' He shrugged. 'I was stupid enough to believe them.'

'I would not worry,' replied Ballista, 'some years ago the same thing happened to a friend of mine.'

The laughter was cut short. A soldier running flat out down the street from the north. 'Men coming! Hundreds of them! Roman regulars.'

Ballista made what dispositions he could with his limited force: a few holding the gate from the temple at their rear, the rest blocking the street. There was no middle way here. It was either very good or very bad.

The noise built – it sounded like a lot of men. Soon such speculation was redundant. The soldiers turned the corner into full view, a solid phalanx of heavily armed men stretching as far as the eye could see. The sound of their coming bounced back off the walls. The shields at the front were those of Legio X Fretensis. Its station was the northern city wall, part of Rutilus's command. And there, bareheaded on horseback, was Rutilus himself. No one could mistake the flaming red hair of the Praetorian Prefect appointed by Quietus. Facing him, Ballista calculated quickly: counting the standards, multiplying the numbers in each rank by those in each file – must be about five hundred. Rutilus had brought the entire vexillatio with him. Further back, there were other standards – at least two auxiliary units.

Rutilus's force did not break stride at the sight of Ballista's men. Inexorably, the shields of Legio X bore down. One hundred paces. They had numbers and momentum on their side. Fifty paces. They would sweep the men facing them aside. Ballista knew being taken alive was not an option. No cell near the surface a second time. The deep dungeons and the claws.

Rutilus yelled a command. The bucinatores sounded their instruments. With a crash, the great phalanx halted.

In the succeeding quiet, Ballista heard a dove cooing from over in the conifer trees of the sacred grove.

The ranks of Legio X parted. Rutilus rode through and out into the space between the lines. All alone, and still bareheaded. He may have always been a faithful servant to the house of Macrianus, but he had never lacked courage.

Ballista stepped out from his meagre ranks.

The two men studied each other.

Rutilus got down from his horse. He untied something, a bag of sorts, from his saddle. He opened it and pulled out a human head. He held it by the hair then let it drop into the dust. His horse skittered sideways, away from the noisome thing. Rutilus prodded the head away with the toe of his boot.

'Death to all traitors,' he said.

The head was unrecognizable. Ballista waited, heart pounding.

'That was the tyrant's cousin and partner in vice – Cornelius Macer.'

Ballista exhaled silently.

Rutilus saluted. 'Ave Imperator Caesar Marcus Clodius Ballista Augustus.'

Behind him, Rutilus's men took up the chant, with only the occasional 'Dives miles' to remind their new Caesar of his obligations.

Rutilus had indeed brought with him all five hundred of Legio X Fretensis, as well as five hundred Armenian bowmen and five hundred dismounted Moorish cavalrymen armed with javelins.

Once Ballista was acquainted with the full force at his disposal, he outlined his plan quickly to Rutilus and the other officers. His original force was to guard the perimeter walls to the north and west and, without taking the risk of becoming too entangled, probe the gate near the service buildings, check the rear entrance. Ballista did not want to ask too much of them. It is always difficult to get men who have once escaped out of combat to go back into it the same day. The dismounted Moors and one hundred of the Armenian archers were to break in the southern gate, secure the sacred grove and prepare to shoot at the Emesenes on the roof of the temple. The men of Legio X would go in via the main east gate and assault the doors of the temple in two units formed in testudo. The remaining four hundred Armenians would follow them and attempt to discourage the men on the roof from intervening. To get them through the temple doors, a work party was to cut down two suitable conifers from the sacred grove as battering rams.

'Is it wise to chop down trees from a sacred grove?' A low muttering of concurrence greeted Rutilus's question. Soldiers were ever superstitious, especially when about to fight. This needed careful handling.

'The god will not hold it against us. It is our enemies – it is Sampsigeramus and his accomplices who have defiled the temple of Elagabalus. They have turned the god's house into a fortress. They have thrown down the sacred images from the roof.' Ballista raised his voice, made it ring. 'The great god Elagabalus offers us his sacred conifers. Elagabalus, Sol Invictus, calls on us to cleanse his house. Elagabalus, the unconquered sun, calls on us to drive out and punish the impious.'

Waiting frays the nerves. It seemed to take an eternity for the various bodies of men to get to their stations, for the huge tree trunks to be manhandled back, their branches lopped off and ends sharpened. Ballista's leg throbbed and stiffened. He felt slightly sick with hunger. His temper was getting short.

A messenger puffed into view. It took him a moment to spot the new emperor slumped against the wall.

'Dominus, the prefect Castricius sent me. Your wife and sons passed over to the lines of Odenathus some time ago, before… before he heard that you had been acclaimed emperor.'

Ballista leapt up. His leg almost gave way as he lunged forward. He folded the messenger in a bearhug, slapping him hard on the back, kissing his cheeks. When released, the man reeled back, quite unsettled by all this imperial affection.

They were safe. Haddudad would make sure of it. Of course, Odenathus now had them, but they had survived – that was all that mattered.

'All ready, Dominus.'

Once more into the arrow storm. But it was different this time. The only Emesenes to be seen were on the roof of the temple. Being shot at by five hundred bowmen from two sides, they mainly kept their heads down.

Encased in their shields like overlapping tiles, the two bodies of legionaries lumbered towards the temple. Inside each testudo, soldiers grunted and swore at the ungainly weight of the improvised battering rams.

They passed the great altar – one of the fires had gone out – and struggled on. Overhead, the fletchings of hundreds of arrows snapped through the air. There was the occasional thump as an Emesene arrowhead hit a shield.

They were at the steps. Holding together, hauling the tree trunk, shuffling up the steps. Ballista fought down the urges to peer upwards, to cower down, to try to get free and run to safety.

A terrible crash. Thank the gods, off to the right. The statue had hit the other testudo. Poor bastards – but thank the gods it was them.

Sheltered under the jutting-out pediment, the legionaries broke out of the testudo. No arrow or falling statue could get them here. They readied themselves. One, two, three… now. Those with the ram swung it into the doors. A hollow boom. Plaster falling from the door frame. The doors shivered, but still stood.

The other testudo reached the shelter. Its legionaries shook themselves into order. Five of their contubernales lay twisted and broken on the steps.

One, two, three… The two rams struck as one. The doors were massive. But their thickness was ornamental. If the god had foreseen this, the architect had not. A splintering, rending sound. The bolts and bars gave. The doors swung inward. The temple was open.

Arrows like disturbed hornets flew out at the faces of the legionaries. A man near Ballista staggered drunkenly, clawing at the shaft protruding from his neck.

Before the second volley, the legionaries charged into the cavernous gloom. They set about their grim work. Blades chopped and slashed. The air was close, thick with incense and the smell of blood.

A line of flickering candle-holders on the floor; beyond, the golden statue of an eagle, and beyond that again, dominating all, the great mass of the black stone loomed up. Huge, dense, pitiless, the top of it lost in the rafters. In front, light silks against the stone's gross negritude, Sampsigeramus.

As Ballista kicked one of the candle-holders out of the way, his right leg gave out. He crashed to the floor. A movement in the choking air. Ballista scrambled, crab-wise, ungainly. The Emesene guardsman's blade sparked off the marble.

The easterner recovered his sword, raised it, came on again. On his arse, leather soles of his boots slipping, Ballista scrambled backwards. He raised his sword. His left hand was empty; somehow, his shield had gone. The Emesene struck. Ballista parried. The Emesene rolled their blades wide. With the advantages of height and weight, the easterner forced Ballista's out of his grip. The heavy spatha skittered away across the floor.

Ballista grabbed a big metal amphora. He swung it round to shield himself. The jar was unexpectedly heavy. It was full; liquid slopped out. The easterner chopped down. A clang of broken metal, the blade cut through the amphora, embedded itself. More liquid sloshed out – it was blood, the detritus of some sacrifice. Holding the handles tight, Ballista twisted the jar, twisted his body, put all his weight into it. They all went sideways – Ballista, the amphora, the sword, the Emesene. They landed hard in a tangle. Hands and feet skidding in the gore, Ballista scrabbled on top of his opponent. Grabbing his hair, he smashed the man's face down into the marble, again and again, in a frenzy. At first the Emesene struggled. Then he did not.

Ballista took the easterner's sword. He crawled over to a pillar and used it to pull himself to his feet. Blood slick on the marble, the dead Emesene, and, lolling out of the top of the ruined amphora, the dismembered arm of a child.

Ballista hobbled over to retrieve his own sword. He felt sick. Obviously, Sampsigeramus had stopped at nothing to try to ensure the support of his ancestral god. The sacrifice of a child had probably seemed a reasonable price to pay for his own survival.

The fighting boomed and swung through the monumental obscurity of the temple. The footfalls of the fighters echoed back as if from an age away.

Sampsigeramus still stood in front of his god. There were fewer guardsmen with him. One lunged at Ballista. The northerner took the blow on the sword in his left hand, severed the man's arm with the one in his right. The guard reeled away; Ballista limped forward.

Sampsigeramus saw him coming. He backed away. Nowhere to go. The stone was behind him. He was screaming incoherently.

The priest-king held his sword in front of him. With a savage blow, Ballista smashed it from his hand. It went spinning into the darkness.

Sampsigeramus turned. With hooked fingers and scrabbling toes, he tried to climb the side of the great black stone. There was no miracle. The smooth stone resisted his efforts.

Ballista dropped the alien sword from his left hand. He gripped the hilt of his own weapon in two hands, steadied himself and swung. The blade bit into flesh, sinew and bone. Sampsigeramus's head jerked sideways, almost severed. The killer of children, the would-be emperor, slid slowly down the side of his god. The blood that pumped so freely ran down the side of the dark stone. Deep in the shiny blackness of the god, the enigmatic markings rippled and moved.

The sunshine was blinding after the shady corridors of the palace. Ballista stood blinking, letting his eyes grow accustomed to it. A grey horse was led out, its trappings purple and gold.

Time to go. As Ballista walked across, a groom hastened up with a mounting block. The northerner thanked him but waved him away. Even in armour, he swung up easily enough into the saddle. His leg was much better. He arranged the imperial cloak, settled the diadem on his head. Leaning forward, he patted Pale Horse's neck, murmured into his ears. Who would have thought we would wear the purple? Enjoy it – like holding a wolf by the ears.

There had been little time. With the death of Sampsigeramus, his supporters – the Emesene warriors, the men of the detachment of Legio III Gallica and the few Roman auxiliaries who had favoured him – had all put down their arms. Yet there had been much to do. Looting had broken out and had to be suppressed. A few high-profile beheadings, nothing too harsh – a dozen outside the palace and the temple, and a similar number in the agora – had taken care of that. Groups of individuals and whole units had left their stations on the city walls. They had been chivvied back into place. A large donative had to be promised to the soldiers and was then paid out of the treasures found in the palace. The family of Sampsigeramus was wealthy, and Quietus's father, Macrianus the Lame, had always been efficient in gathering money. Now, for a brief time until the bar and brothel owners took it, the milites were dives indeed. At a more exalted level, the army high command had been confirmed: Rutilus remained Praetorian Prefect and Castricius Prefect of Cavalry.

All the soldiers, from Rutilus as Praetorian Prefect to the lowest Emesene militiaman, had hurriedly taken the sacramentum. One from each unit had recited the oath: 'By Jupiter Optimus Maximus and all the gods, I swear to carry out the emperor's commands, never desert the standards or shirk death, to value the safety of the emperor above everything.' Then all the others had shouted, 'Me too!' It had always struck Ballista as slightly comic, but when addressed to himself, it came close to a ludicrous mime or farce.

Then there were the issues of familiarity and contempt. To how many emperors had these men given their oath? For a veteran nearing the end of his twenty years, there would have been a horde of imperatores: Gordian III, Philip the Arab, Decius, Gallus, Aemilianus, Valerian, Gallienus, Macrianus and Quietus. And that was if he had not followed any of the many ephemeral pretenders such as Iotapianus or Uranius Antoninus. And now there was Imperator Caesar Marcus Clodius Ballista Augustus.

So many oaths given. So many oaths broken. The new emperor knew all about that. Gone is the trust to be placed in oaths; I cannot understand if the gods you swore by then no longer rule, or if men live by new standards of what is right?

Ballista made a sign. Ahala rode up behind him and unfurled the northerner's white draco. The Equites Singulares fell in behind Ahala. Ballista waved, and they set off.

The streets were muted. Both soldiers and civilians acknowledged the cavalcade, yet the cheers were tentative, uncertain, and those he passed performed the lesser form of proskynesis. Of course, they knew the purpose of Ballista's ride – even if the outcome was in deepest doubt.

At the Palmyra Gate, the others were waiting on horseback. Ballista dismissed the cavalry guard, except for his new standard bearer. He spoke briefly with Castricius, who was to remain behind to ensure order in Emesa. Leaning far out of the saddle, they embraced and said farewell.

Ballista looked down the line at who would go with him. Ahala carried the draco directly behind him. Then, in columns of twos, were Rutilus and three senatorial governors. It had not only been the army Ballista had had to conciliate. Fabius Labeo, the noble and surprisingly resilient governor of Syria Coele, would probably have been grateful enough just to have been released from his iron cage over the northern gate. But he, like Cornicula of Syria Phoenice and Achaeus of Syria Palestina, had received substantial material inducements to join the new regime. It slightly rankled with Ballista. He had a healthy dislike of the religious bigot Achaeus but, ultimately, it was not his money. The avarice and ruthless efficiency of Macrianus the Lame had proved useful. For the moment at least, the three governors followed Ballista Augustus.

The gates squealed open. As he rode under the tall arch, Ballista saw the sculptures of the eagle, altar and black stone of Elagabalus and the innumerable scratched prayers for a safe journey. It was not his god, and it was not his way. Allfather, Deep Hood, Death-blinder, keep your one eye on your descendant.

The little column of six riders went on. Past the stark, stained crosses, the ornamented tombs of the necropolis. Across two hundred paces of no-man's land. Through the lines of the besieging Palmyrene army. Dark eyes, expressionless faces watched them. Up to the open space in front of the great tent, where the many standards flew.

The Lion of the Sun was seated on the ivory-trimmed curule throne of a high Roman magistrate. Odenathus was backed by his court. On one hand were his chief minister Verodes, two of his generals, Zabda and Haddudad, and the son by his first marriage, Haeranes – now grown into an active-looking young man. On the other stood the Romans: Pomponius Bassus, governor of Cappadocia; Virius Lupus, governor of Arabia; and Maeonius Astyanax, sometime Praetorian Prefect of the rebels Macrianus and Quietus – may their names everywhere suffer damnatio memoriae. In the background, but determined not to be left out, was his current wife. Zenobia was holding by the hand their infant son, Vaballathus, or Wahballat, as some called him. With her were a couple of earnest, hirsute men in Greek dress.

The entourage of the Lord of Tadmor was splendid in burnished steel, gilded armour and bright, nodding plumes. But the open space was dominated by someone else. More than half lifesize, the emperor Gallienus stood to one side. Brows furrowed, eyes hooded, the statue looked down on the scene. Ballista was reminded of a story that the successors of Alexander could only be brought to meet together if presided over by the empty chair of the great Macedonian.

Ballista dismounted. Those behind him did the same. Grooms took their horses away. Ballista took a couple of paces forward and stopped.

Odenathus rose from the curule chair. He was wearing a western-style corselet with big, buckled-down shoulder guards. On his arms and legs were cunningly embroidered eastern tunic and trousers. A golden brooch on his right shoulder secured a scarlet cloak; it was matched by a scarlet sash tied around his waist. His left hand was closed around the hilt of his long sword. The pommel was in the shape of a flower. The Lion of the Sun was magnificent, his painted face inscrutable.

The two principals regarded each other, in the background the unnatural silence of the crowd, the hiss and snap of the standards, the silica sounds of the breeze moving the sands – patterns fleeting across the surface.

Ballista walked to the statue of Gallienus. Under his long nose, Gallienus's beak-like mouth seemed set in disapproval. Ballista unclasped his purple cloak and set it at the feet of the statue. Then he took off his diadem and placed the strip of white material on top of the cloak.

Slowly, Ballista performed proskynesis in front of the statue. He got up and turned back to Odenathus.

In a confident, strong-voiced Latin, Ballista began: 'For the safety of the Res Publica, the soldiers demanded that I take power. Having killed the usurper, I now lay down all my power at the feet of my rightful emperor Publius Licinius Egnatius Gallienus Augustus. I give myself to his clementia in the person of his Corrector totius Orientis, Odenathus of Palmyra.'

At long last, the Lion of the Sun spoke. 'How slowly and painfully should I kill a man who has the arrogance to assume the trappings of imperial power?'

Ballista stood where he was.

'Or there again, no.' Odenathus smiled. 'By the maius imperium over the eastern provinces entrusted in me by Gallienus Augustus, I declare Marcus Clodius Ballista innocent of any and all charges of maiestas.'

The two men stepped forward, and formally embraced.

'Let them come out,' Odenathus called over his shoulder.

Isangrim, Dernhelm – his darling boys – Julia, and Maximus, Calgacus; all here, all safe.

'The throne of the Caesars is too high an eminence for weaklings like Quietus, or even for men like us,' said the Lion of the Sun.

Safe back in the arms of his familia, Ballista agreed.

And all unnoticed at the back, Zenobia scowled and whispered to Maeonius Astyanax.