For the rest of that day they marched, up the hill from the encampment and on over high desolate moorland. There was only a small group of guards, twenty or thirty warriors with spears, and they moved at a steady lope, dragging Castus along with a halter around his neck. Marcellinus they carried on a crude stretcher, his broken leg wrapped in fleece.
Whenever he could, Castus straightened his back against the wood at his neck and gazed around him, trying to pick out landmarks he might remember, trying to gauge distance and direction. The sky was overcast, but as the day wore on he saw his shadow before him and slightly to his right, and knew they were travelling north-east-by-east. They crossed the mountain flank and descended, following a rushing stream into a broad valley that stretched almost to the northern horizon.
As evening came on he saw fires on the hilltops: beacons, and here and there the walls of small forts. Smaller fires moved in the valley below: lines of men with torches, streaming westwards towards the tribal muster. One small victory over Rome was not enough for them, Castus realised. Now the whole nation of the Picts was rising. He thought of his men, Timotheus and the rest, marching at full pace towards the frontier, with the Pictish horde surging behind them. He could not afford to think about these things. Only survival mattered now. Survival and, one day, vengeance – for Strabo, for the dishonoured bodies of his fallen soldiers, for the jubilation of the barbarians around their trophy tree. One day, he thought – and the hunger for that vengeance drove him on.
When night fell the guards led them up to one of the hill forts, a ring of stone set on a spur above a valley cleft into the mountainside. At the centre of the fort was a broken tower of massive masonry, and they built a large fire against the wall of it. The flames curled up over the mossy stones, throwing huge rearing shadows onto the surrounding hillsides. Castus lay at the edge of the light, chewing a hank of dried meat, with Marcellinus on his stretcher beside him.
‘Stupid of me,’ Marcellinus said, ‘to try and intervene like that. I couldn’t have done anything to stop them.’
‘Suppose not,’ Castus said. He would have done the same, he knew, if he hadn’t had a spear pressed into his throat.
Marcellinus was silent for a while. His broken leg was clearly paining him, but he was trying not to let it show.
‘So it was Talorcagus and his nephew,’ Castus said, ‘who poisoned the other chiefs.’
‘Almost certainly. And they probably killed Vepogenus too. And now they have the power to kill anyone who accuses them of it.’
‘And what about the woman… Cunomagla, you called her. Wasn’t she the wife of Vendognus?’
‘She was. Now his widow. But there was no love between the two of them. I wouldn’t be surprised if she was part of the conspiracy as well. With her husband gone she’s free to advance her own son as future king… Which puts her in competition with Drustagnus, of course…’
‘If they start fighting among themselves,’ Castus said, ‘all the better for us. What about Decentius, the renegade? Did you see him? I stuck a dart in his leg.’
‘You did? Good…’ Marcellinus managed to smile. ‘I didn’t see him, no. He’ll be around somewhere, though, if he lived. He’s sure to be involved in the plot.’
Castus frowned, remembering something he had forgotten in all the confusion of the last twelve hours. ‘He said… Decentius, I mean… he said something about the empire betraying us. Sending us to die deliberately. What did he mean?’
Marcellinus lay still. Perhaps thinking, Castus told himself. Perhaps trying to frame an acceptable answer.
‘I don’t know,’ the envoy said at last. ‘I confess I heard something similar from Strabo – he was taken away to meet with Decentius during our captivity.’
Castus decided to ask no more about it, for now. He gnawed off another bite of the dried meat and squeezed it between his molars. Whatever might have happened – or not – in the muttered conversations of conspiracy was nothing to do with him.
‘Can I ask you something?’ Marcellinus said.
Castus nodded. The meat was sticking his teeth together.
‘Why did you agree to surrender back there? I mean – what was going through your mind?’
The meat came free, and Castus swallowed it. He took his time before answering.
‘Your daughter… made me swear an oath. To protect you.’
‘Marcellina? She made you do that?’
‘Yes. To protect you and bring you home safely.’
Marcellinus tipped his head back. ‘Ha, aha!’ he said, gasping against the pain as he laughed. ‘Ha ha ha!’
In the grey of morning they set off again, moving north-east along a narrow track between the mountain slopes and the wide plain of the valley. The sky had cleared, and the sun shy;light came down in bright torrents, lighting the landscape to grey-green and golden brown. The hills and the plain below were striped with the rolling shadows of clouds and, in the far distance, the northern horizon was lined with bare blue mountains.
After five or six miles they forded a wide stream; then the trail swung eastwards. There were settlements of clustered huts across the plain, and the coils of a winding river glinting in the sunlight. The baulk of wood chafed against Castus’s neck with every step, and he could no longer feel his hands, but he kept marching.
Finally, as the sun set behind the hills, the trail curled around into a narrow valley and began to climb. The slope rose, until Castus could barely stagger upwards with his shoulders bent. He glanced up and saw a wall of massive stones looming above him in the twilight, almost twelve feet high with a wooden palisade along the top. The guards led him around the base of the wall, then up into a narrow opening between the rearing ramparts. A stone-lined passage, open to the sky above, sloped on upwards. The guards cried out to the men on the wall above them, and a heavy wooden gate opened.
Fatigue coursed through his body as Castus climbed from the entrance passage into the enclosure of the fort. Round huts with conical roofs of straw and turf packed the raised terrace inside the stone rampart and palisade. Dogs barked from the darkness and torches flared bright in his face. Still he was led onward, between the huts to a second, higher wall that lay within the first. Another narrow cleft led upwards; goaded with a spear at his back, Castus stumbled through the gap and climbed towards the upper terrace of the fort.
Three or four large huts and a cluster of smaller ones stood at the centre of the enclosure, with smoke rising into the still night sky. Castus snatched a look back over his shoulder at the darkened landscape to the north, the wide spread of the valley, but rough hands pushed his head down, and he felt himself shoved forward into a low confined space. Behind him he heard Marcellinus cry out in pain; then he was wrestled off his feet and his hands were untied from the baulk of wood. The ground seemed to vanish from beneath him, and for a moment he was falling, before hard stone rushed up and struck him in the back. He lay still, breathing quickly, blood pumping through his body. Stone all around him – hard and cold and deep. He took a deep shuddering breath as the dread crawled through him. Then he began shouting.
‘Are you awake? Can you hear me?’
‘Yes… Where are you?’
‘Over here – I can reach your ankle… Do you feel that?’
‘Where are we?’
‘Underground. A storage chamber in the fort. You’re safe, don’t worry. Just don’t sit up – the ceiling’s very low and you’ll hit your head again. That was quite a clout they gave you when you started yelling. You’ve been unconscious, I think.’
Castus was lying down in total darkness, and when he raised his arms his knuckles grazed stone to either side. The chamber was more like a tunnel, barely four feet across and lined on all sides with heavy slabs. Like a sewer, he thought. Like a grave.