The headman of Chabala was welcoming. He told them what they wanted to know. Cosis, king of Albania, was on the Caspian coast, south of the big peninsula, in the territory of the Cadusii. His uncle, Zober the high-priest, was with him. They had gone to confer with Prince Narseh, the son of Shapur. Yes, Narseh had his troops with him – many myriads – for there were still those unpunished among the Cadusii. Yes, the headman thought the Roman Castricius was with Cosis.

They rested for a day in the headman’s house. When they left, he gave them gifts and food, provided two warriors who would act as guides. A day in the saddle brought them down to an immense lowland plain. It was hot down there. Yet not so hot they would put off their armour.

They rode hard for three days, but the news of their coming preceded them. No fewer than one hundred mounted Albanian warriors were waiting for them. They were large, handsome men, dressed much like Persians or Armenians. They were armed to the teeth: bows, javelins, swords, many daggers; wearing breastplates and curious helmets made from the skins of wild animals. The leader at least spoke Greek. He welcomed the kyria Pythonissa with all politeness – his basileus Cosis greatly looked forward to entertaining her. With Ballista he was more reserved – it was his duty to take him with all speed to Narseh, the glorious son of the house of Sasan. On the type of welcome Ballista might receive he would not be drawn.

To reach the sea, they crossed the strangest landscape Ballista had ever seen. The path ran through nothing but miles of crazed, cracked mud. In places it pushed up to resemble small hillocks or large anthills. From these eminences, hot, liquid mud flowed; darker than its solidified antecedents. There was no animal or plant life. The smell was repulsive, like naphtha. It was like riding back into primordial chaos, back before Prometheus had moulded man from the foul stuff around them.

Finally, there were clumps of coarse grass, patches of sand. The mud gave way to the shore. The sea breeze blew away most of the stench. And there on the silted coastline was the camp. The horselines stretched into the distance. To Ballista’s experienced eye, there were some ten thousand horsemen and a horde of others – infantry and camp followers, Persians and Albanians all indiscriminate.

The camp was dominated by two pavilions, both purple, one larger than the other. The men were led in front of them, told to dismount. Pythonissa and her eunuch were ushered straight inside the smaller of the tents. Ballista and Maximus were told to wait. The Albanian guards were replaced by Persians. Beyond the camp, the line of the sea was decorated with men impaled on poles. It could have been the wind coming off the sea, but one or two of them seemed still to be moving.

‘Did you know, the Caspian is a lake?’ Maximus asked.

‘No, it is not.’

‘Sure it is – sweet water and snakes. I know about snakes.’

‘Did you know that among the many poisonous snakes in Albania there is one whose bite causes men to die laughing?’

‘Fuck off.’

‘And another with venom that brings you to death weeping and mourning for your ancestors.’

‘What if you did not know who your father was?’

‘You would probably cry about that.’ Ballista inclined his head. ‘We are drawing a crowd.’

‘Well, you cannot blame them, it is not every day Nasu the daemon of death comes calling cap in hand.’ Maximus looked somewhere else. ‘Do you think we will be joining the boys on the shore?’

‘No, I would not have come if I thought that.’

‘You do not sound so sure now.’

‘No, I am not so sure now.’

A Sassanid noble walked out of the pavilion. He was tall, broad-shouldered with slim hips. The silk surcoat over his steel was heavily embroidered, predominantly light blue. His beard was dyed bright red, and his eyes were lined with kohl. Some years before, Ballista would have laughed. That was before he had seen such men fight.

The Persian greeted them suavely in Greek. He asked them to accompany him into the presence of Prince Narseh. Ballista knew that such civility was only to be expected in a man of such rank from the Orient. It signified nothing about their fate.

They passed through the outer chamber of the marquee, where petitioners waited in silence. They were not told to remove their weapons – that might be a good sign.

The inner sanctum was a slightly smaller version of that of the King of Kings Shapur himself: purple and gold opulence in everything. Ballista pushed away the memories. He had to keep his concentration. Everything might depend on it.

The son of Shapur sat on a throne at the far end. Ballista and Maximus advanced – not too close – and made full proskynesis. Face down on a Persian rug, Ballista accepted that this was not the time for an assertion of either Roman dignitas or Germanic freedom. Having blown the ritual kiss, they got to their knees, then their feet.

Prince Narseh was a good-looking young man, with an aquiline nose above a curly blue-black beard. He wore a tiara and an enormous pearl hanging from each ear. He was flanked on his right by officers, on his left by mobads. Ballista did not recognize any of them. A Zoroastrian fire altar burnt in front of the priests. Soldiers in armour lined the walls.

‘I know you well, Dernhelm son of Isangrim.’ Narseh spoke excellent old-fashioned Attic Greek. ‘The barbarian from the frozen north where lies the mouth of hell. Marcus Clodius Ballista, the man who would have been king of the Romans – if only for five days, in just one town in Syria.’

The courtiers laughed.

‘The man who tried to kill my father at Arete, who raped the favourite concubine of the King of Kings at Soli. The oath-breaker who reneged on what he promised at Edessa.’

No one in the pavilion was laughing now.

‘The unrighteous one who defiled the purity of fire with the corpses of the slain at Circesium, the sacrilegious one who extinguished the fire altar in the tent of Shapur. The servant of Ahriman who has the temerity to style himself Nasu the daemon of death. And he brings with him his heartless killer, the ex-gladiator Maximus.’

It was very still in the pavilion. The sacred fire crackled.

‘Mazda is the supreme requiter – none of the wicked is so high or low as to escape him either by force or by stealth. We of the house of the Mazda-loving king Sasan follow the customs laid down by our ancestors. The torture of the boats is an ancient Persian punishment. The malefactor is laid on his back in a boat. Another boat, carefully adjusted, is nailed over the first. Only the criminal’s head, hands and feet protrude. He is given good food to eat, milk and honey to drink. If he refuses, his eyes are pricked until he takes it. The sweet drink is tipped over his face. He is left, facing the sun. A swarm of flies descends to cover his face. Inside the boat, sooner or later, he does what must needs be done when men eat and drink. In time, worms and maggots seethe up from the corruption and rottenness of his excrement. Slowly they devour his body, eat their way into his vitals. It is not a quick death. Men have lived as long as seventeen days in the torture of the boats.’

Ballista held himself on such a tight rein he could not speak. Even his thoughts were stifled. He had been a fool to come here. Now he would be killed, and he had brought Maximus to this horrible death.

‘The Greeks and Romans traduce us when they talk of Persian cruelty.’ Narseh continued in the same flat tone of voice. ‘With us, even a slave has his services weighed against the number and gravity of his crimes before he is sentenced. It is true that you, Ballista, were gracious when mischance and the evil of the tent-dwelling Arabs brought one of the mobads into your house as a slave. Again, no one can deny that in Cilicia at the place of blood you saved the life of my brother Valash, the joy of our father Shapur.’

The faint flicker of hope in Ballista was stamped out by the next words of Narseh.

‘There are many crimes born in the darkness in the hearts of men. Mazda inspired our ancestors to create as many fitting punishments. Bring in the crosses.’

Six men in the soiled costume of labourers dragged in two crosses. They rolled back the carpets, set the crosses upright. In the previously quiet space the noise was fearsome as they hammered the wicked-looking things into the sandy soil.

The workmen left. They were replaced by four executioners; two held knotted whips, and two long swords.

This was all happening too fast. Ballista knew he had to do something. ‘Prince Narseh, son of…’

‘Silence,’ Narseh ordered. ‘Your words will change nothing. Strip them.’

It was no sooner said than done. Strong arms seized Ballista and Maximus. They were disarmed. Their hats, cloaks and armour were pulled off. They were left standing in their travel-stained tunics.

‘Five hundred lashes. Cut off their ears and then their heads. Carry out the punishment.’

Allfather, Ballista began to pray. He doubted they would survive the scourging to feel the severing of their ears. Allfather…

The executioners draped the cloaks of Ballista and Maximus over the crosses, tied them in place, fixed their native hats firmly on top. The ones with the whips steadied themselves, and then swung. With the utmost seriousness they went about their work. After a few strokes, the knots in the whips had torn great rents in the cloaks.

The condemned men began to laugh. A court official told them it was customary for men in their position to beg for mercy. Sheepishly, they both bleated, ‘Mercy,’ once or twice, quietly.

The men with the whips were running with sweat, panting hard, by the time they had finished. It had taken a long time. They had not stinted themselves. The cloaks were in shreds. The two with the swords approached the crosses. With a deftness approaching artistry, they sliced the lappets from the native caps – first one ear, then the other. A flourish of the blades, and the headgear was cut in two.

‘Humanity and piety are the kindly sisters of the virtues,’ Narseh said. ‘Valash and I have always been close. I could not stand my brother’s anger if I had killed his saviour. Besides, I believe we have much to discuss.’

XXIX

This paradise turned out to be roughly circular. As such places went, it was rather smaller than Ballista had imagined, not much more than a couple of miles in diameter from wall to wall. But there, it was an Albanian paradise, not a Persian one. They rode apart from one another. The horses, thin legs skittering, were dark shapes moving at a fast trot through the verticals of the trees. The riders were taking care not to catch their long spears in the branches.

Ballista was worried at the time it was all taking. Four days had passed in the camp on the Caspian shore after the symbolic punishment of him and Maximus. It had taken two days to ride up here into the foothills. Another three days had elapsed while the paradise was prepared. It was now, he reckoned, just short of a month since Saurmag had welcomed the Alani through the Caspian Gates. If they still held out, Calgacus and the others had been besieged in Cumania for twenty-five days. If they still held out. The little fort was strong, very strong. They should have more than enough provisions, ready access to water. But anything could have happened: treachery was an ever-present danger. Ballista was far from complacent.

The bright coats of the beaters flared through the shadows of the trees. The hounds, leashed now, surged about their legs, snarling. The riders trotted up, swung down, passed the reins to attendants and hefted the stout spears with the broad blades and wide cross-pieces.

‘He is in there.’ The chief huntsman pointed to a thick, broad tangle of undergrowth on the banks of a stream. There was clear ground in front, the only obstructions the wide-spaced trunks of a stand of mature beech trees. Prince Narseh told the head of the beaters to take his men across the stream, wait for the command and then slip in the hounds all at once from that side. Narseh spoke in Persian. Ballista considered whether the Sassanid prince knew that he and Maximus understood. They had been careful not to speak the language since they arrived at the camp. It was important to keep close anything that might be of advantage.

‘We will take our stand here. Spread out among the trees, in the shape of the half-moon, we will cut off all ways of escape.’ Now Narseh spoke in Greek to those around him. He turned to Pythonissa. ‘ Kyria, it would be best if you were with the guards.’