The Armata slipped into the clammy embrace of the fog. Instantly, the temperature dropped. The sweat ran cold between the men’s shoulderblades. Their breath plumed. Wraiths of mist slipped inboard past the bow post, snaked down among the benches. A pall of steam rose from the rowers, adding to the gloom. It was getting hard to see from one end of the boat to the other.

A murmur of tired voices from the oarsmen; the stroke became ragged, desultory. ‘Silence!’ Bruteddius’s voice was pitched to carry, but not far. ‘Not safe yet, pueri, just a little more. Easy pressure.’

The Armata ghosted through an opaque world. The creak and splash of the oars, the soft gurgle of water. The fog pearled on everything: deck, oars, rails. It dripped from the crew’s beards.

Ballista watched Bruteddius staring over the stern into the fog. All the officers, everyone watched Bruteddius. Nothing visible, no sound of pursuit. Neither meant anything.

Bruteddius softly called for the purser. ‘ Pentekontarchos, break out the food and water.’ The officer padded away, the mist swirling behind him. ‘Where is the naupegos?’

‘Here, Dominus,’ said the shipwright.

‘Bring up the thin papyrus rope and all the tallow.’ Bruteddius did not glance at the man, never looked inboard.

‘ Dominus.’

Under the eye of the pentekontarchos, the rear watch of the deck crew was piling wrapped bundles and amphorae on the quarterdeck.

Bruteddius turned to survey his ship. ‘ Thalamians, cease rowing, oars inboard.’ Gratefully, the rowers on the lowest level obeyed. ‘ Pentekontarchos, feed the thalamians first.’ Bruteddius turned back to the wall of fog beyond the sternpost.

Bread, both soggy and slightly stale, a lump of cheese, a raw onion, and a long drink of heavily watered wine; not having eaten since dawn, the thalamians wolfed it down. It was gone in seconds.

‘ Zygians, cease rowing, oars inboard.’ The procedure was repeated with the middle level, leaving the top level, the elite thranites, rowing the boat on their own.

The naupegos announced the things were to hand.

‘Good, shipwright,’ Bruteddius said. ‘ Zygians and thalmians, strip.’

Ballista and the other passengers watched, bemused, as the two lower levels of rowers stripped off their things with no question or complaint. The hundred or so men sat naked or in undergarments, most shivering with cold and exhaustion. Bruteddius glanced over his shoulder and smiled. ‘Good, pueri. Now muffle your oars with your tunics; tie them tight with bits of rope. Grease the oarports.’

The cloying smell of rancid mutton fat wafted as the men began to rub the tallow into the leather sleeves which kept the water out of the oarports. It mingled with the stench from the bilges: stale water and sweat, human waste. No oarsman had left his bench for hours. They had had to relieve themselves where they sat. It had not been good for the men on the lower levels. They reeked of piss and shit. Ballista felt sick in the choking miasma.

‘ Thalamians, oars out. Gentle pressure. Row. Thranites, oars inboard; eat, then do the other things.’

‘What do we do?’ Ballista addressed the question to Bruteddius’s back.

The trierarch tipped his head to one side, took his time answering. When he did, he did not look round. ‘We could continue on our present course: three hundred miles of sea room to the Island of Achilles or the mouths of the Danube. It has the advantage that the Goths will not think we will do that. It has the disadvantage that, unless an easterly wind gets up, we would never get there. We have no more food, only enough water to last until the morning.’

Bruteddius paused, tipped his head to the other side. ‘We could head north: a long day’s row to the Crimea. But what sort of reception would we get?’

‘Come.’ Felix broke in. ‘It is not the heroic age. They do not sacrifice strangers there any more. The king of the Crimean Bosphorus is a loyal client of Rome.’

‘The Goths got the liburnian somewhere,’ said Bruteddius thoughtfully.

Before Felix could reply, Ballista spoke. ‘When the Borani first raided into the Black Sea, the time Successianus defended Pityus, they forced the cities of the north-west and the king… some of the subjects of the king of the Crimean Bosphorus to provide them with ships.’

‘Or we could run south,’ Bruteddius continued. ‘We might run into the two Goths who were off to larboard. If we got there, would we be safe? The nearest detachment of auxiliaries is in Heraclea, and precious few of them. It depends how badly the Goths want us.’

Again, Bruteddius paused. Ballista leant on the stern rail next to him. The trierarch’s face was very still, but his eyes did not stop moving, probing the impenetrable fog. ‘We could stay here, sit quiet,’ Bruteddius continued. ‘Hope that either the Goths pass us in the fog or give up when they see it. The men are exhausted. They could rest. But, if the Goths came on us, with no way on the boat, we would be a sitting target.’

This time Bruteddius was silent for longer.

‘And our final option? Ballista asked.

‘Our final option is to turn back, try to run silently through them in the fog and the night, get to a safe harbour in Sinope, or even all the way to Trapezus. Best to try and take on water and food somewhere along the coast and then press on to Trapezus. There are troops there.’

‘And that is what we will do?’ said Ballista.

‘That is what we will do,’ said Bruteddius.

Half an hour, and the Armata was facing east again. During this time, the thranites had rested, but now they had to return to their work. The top level consisted of the chosen men, the best oarsmen in the boat. Hard men, nut brown; it was said they could row from dawn to dawn with just a sip or two of water. Now that claim would be put to the test. Their hard, callused hands played out the long, smooth shafts of fir. One rank of blades would make less noise. The thranites would row with more control, more quietly than the zygians or thalamians. It had to be them. They took pride in it. A soft word from the rowing master and they began. Slowly, the Armata got under way.

It was near sunset. Somewhere behind, the sun was going down. Only a faint lightness in the billowing clouds of fog, a strange hint of refracted colour, indicated the west.

The great galley slid forward. No pipes, no songs; the thranites kept time instinctively, watching the backs of the men in front. Catch, pull, twist and lift. A slight swell had got up from aft, gently lifting the stern, running under the keel. Nothing to trouble the thranites. The wings of oars rose and fell with the quietest of splashes. The ram nosed through the water with a restrained, sibilant hiss.

Ballista stood in the stern with Bruteddius. The trierarch, legs splayed, rocked as one with the movement of his boat. His eyes were never still. They flicked from the thranites to the prow, where the bow officer was leaning far forward, watching, listening.

The fog was thick, tangible. Yet every so often, a space cleared, like a glade in a forest. The boat pushed through, back into the gloom.

Bauto brought Ballista a small cup of unmixed wine. The Frisian was meant to be Calgacus’s servant, but he and Wulfstan tended to Ballista and the old Caledonian indiscriminately. They were good boys.

As he sipped the alcohol, Ballista looked down the length of the long, narrow craft. Below the thranites, the other rowers were asleep on their benches, a hundred or so men huddled in strange attitudes. Beyond exhaustion, they lay, limbs overlapping, like animals in a malodorous den.

A seagull swooped from nowhere, its cry harsh and shocking. Bauto jumped. Ballista put a hand on his shoulder, smiled a reassurance he did not feel. The bird was gone.

The Armata slipped wraithlike through the coils of clinging vapour. Ballista’s eyes itched with tiredness. Time had lost all meaning. It was darker. The rhythm of the thranites was hypnotic. They could have been rowing for hours.

The brazen note of a horn rang out. Horrible in its immediacy, it came from somewhere not far off the larboard bow. Everyone froze. Even the thranites faltered. A sharp, urgent whisper from the rowing master amidships, and the rhythm was resumed.

Another horn answered, then another, both off to starboard. Behind Ballista, a man sniffed loudly. He swung round to cuff him to silence. It was Felix. Ballista did nothing.

More horns, seemingly all around. Allfather, they were in the middle of the enemy. Ballista looked at the others on the quarterdeck. Everyone was unnaturally still. Maximus’s eyes were shut; he was listening. Bruteddius glanced back; a tight smile. The boat glided on.

A disembodied voice floated through the fog. Ballista held his breath. The creak and splash of the oars was hideously strident. The voice came again; muffled, a little off to the left.

‘Cease rowing.’ Only the nearest oarsmen could hear Bruteddius. Those further away followed their lead. The boat’s mo- mentum carried her on.

Another voice, much nearer, to the right. It was German; a question, the words indistinct.

Ballista’s breathing was shallow, panting. He was gripping the sternpost tight, sweating. Around him, the faces of the others were sheened with moisture. Their heads turned this way and that, peering at things they could not see.

The voice came again from the right, nearer still: a hail, a man’s name.

Even the helmsman was trembling. No one was sleeping on the lower benches now. All the men kept glancing at Bruteddius. The trierarch was rock still. If the hail was aimed at them, it was over. The boat was losing way.

Off the starboard bow, something darker than the mist, more solid. A hundred feet, no more: the upswept stern of a galley – the liburnian . The Armata was nearly dead in the water.

A Gothic voice returned the call; clean over the Armata, from further away to the left.

The horns started up again, the notes eddying through the fog.

Bruteddius padded to the nearest oarsmen. He spoke so low that Ballista and the others by the helmsman did not hear. Drops of water fell from the oars as the thranites glanced over their shoulders at the men behind, readied themselves. Bruteddius, nodding calmly, gestured to the two rowers on either side closest to him. They looked at each other, began the stroke. The others copied.

The splash as the blades bit the surface, the creak of wood, the slosh of water. Surely the Goths must hear. One stroke, a second. No outcry yet. The many thousand wooden joints sighed as the ship gathered way. Still no alarm. Someone was muttering a prayer. Another hushed him.

Yet more horns, their piercing volume a blessing from the gods. The dark, solid shape to the right faded aft. In moments, the fog blanketed the sounds of the horns. Ballista drew an almost sobbing breath. The Armata sailed on into the opaque, dark night.