Then he was aware of someone walking down to the river bank about fifty paces upstream. The huge frame of Figulus squatted down in the grass, a length of straw tilting from the Gaul's lips as he gazed into the river. Figulus slowly looked round and then fixed on the centurion sitting beneath the willow, and he rose to his feet, hesitated a moment and then walked towards Macro.

'Shit,' the centurion whispered to himself.

Macro was tempted to tell Figulus to get lost. He had come down to the river to get some time to think things through alone, and the prospect of talking to the optio made his heart feel leaden. Then he realised that Figulus too must be dreading Cato's fate. Macro relented and made himself smile as Figulus approached him. The optio stiffened and saluted.

'It's all right, lad. We're off duty for the moment. You can drop the bullshit.'

'Yes, sir.' Figulus hovered back, a few paces outside the thin curtain of leafy tendrils.

Macro sighed. 'You got something you want to say to me?' The optio lowered his head a little and nodded.

'Out with it then.'

'Yes, sir.'

'And do sit down in the shade, before the sun boils your tiny brain.'

'Yes, sir.'

Figulus raised a thickly muscled arm and swept the leaves aside, blotting out the sun as he towered over Macro for an instant, and then squatted down, keeping a respectful pace away from his superior.

'Well?'

Figulus looked up sharply, his straw eyebrows coming together in a frustrated expression. 'It's Centurion Cato, sir. They've no right to do this to him. It ain't fucking fair. Pardon my language, sir.'

Macro looked at him sidelong. 'Yes, you want to watch that. Doesn't become an officer at all.'

'Sorry, sir.' Figulus nodded seriously. 'Won't happen again.'

'See that it fucking doesn't, then.'

Figulus looked startled for a moment, then Macro relaxed his stern expression and grinned. 'Just taking the piss, lad.'

'Oh, right…'

Macro's smile faded. 'As far as Cato goes, I'm afraid there's nothing we can do. Nothing. Orders is orders. You'll have to get used to that now that you're acting centurion. How's it going?'

Figulus shrugged unhappily, and reached out for one of the strands of willow before he realised that Macro was idly stripping a branch. His hand froze, and then dropped back to his side as he decided that it would be bad form to be seen to be aping his superior so openly. So his fingers scrabbled for one of the pebbles that lay in the loose, dry earth where the bank crumbled into the slow current. He tossed it in his hand and then threw the stone out over the river, where a small explosion in the glassy surface marked its fall. He watched the ripples fade before he spoke again without turning to Macro.

'There must be something we can do about it, sir.'

'Like what?'

'We go and see the legate.'

Macro shook his head.'I'm telling you, he won't change his mind.'

'The general then.'

'He definitely won't listen. Plautius would probably throw us in with them if we so much as breathed a word of protest in his hearing. Besides,' Macro shrugged, 'what could we say? That it's not fair? That's not going to work. Our unit fucked up, and in a way that looked awfully like we didn't have the balls to do the job. Nobody's going to let the Third Cohort off the hook.'

'But we didn't run. Maximius ordered us to fall back. He's the reason we never made it to the ford in time in the first place. He should be taking the blame, not Cato and all the rest, sir.'

Macro twisted towards the optio. 'You think I don't know that? You think I don't give a shit about them? I'm telling you, Figulus, the whole bloody legion knows the score. I'd be surprised if the whole army didn't. But someone has to pay the price for this almightly balls-up and fate has gone and picked on Cato. It ain't fair, you're right there. It's just bad luck. Sticks in my gut just as much as yours.'

Both men turned to watch the figures swimming on the far side of the river, then Macro idly started to doodle in the dust with the end of the length of branch he had stripped. He cleared his throat. 'But you're right. Someone should do something about it…'

As a cool dusk settled over the land Cato found himself shivering. His head ached badly. He and the others had been forced to sit in the blazing sun all through the day and now the exposed parts of his skin felt tight and tingled painfully. Only as the day had ended had the sky become overcast and the air filled with a clammy closeness that threatened rain. Cato took this as a further sign that the gods had wholly abandoned him: tormented by the sun during the day and cold and wet by night.

One of the camp slaves had brought a few canteens of water up from the river and each man had been permitted a few mouthfuls to wet their dried throats. But there had been no food. When rations were in short supply condemned men were the first to go without. It made sense, Cato told himself. It was the logical thing to do.

About the only logical thing to be happening in the present circumstances. The fact that he had done nothing to merit tomorrow's punishment was tormenting him more than any other thought. He had faced the enemy in battle, when a moment's carelessness would have seen him dead. He had undertaken a perilous quest to find and snatch the general's family from the heart of a druid stronghold. He had risked being burned alive to save Macro in that village in Germania nearly two years ago. Every one of those actions had been fraught with terrible risks, and he had entered into them knowing and accepting the danger. To have been killed at any of those times would have been a reasonable consequence of the dangers he had exposed himself to. That was the price paid by men of his profession.

But this? This cold-blooded execution designed to act as an example to the other legionaries? An example of what, precisely? An example of what happens to cowards. But he was no coward. To be sure he had been afraid more times than he would care to admit – terrified, even. That he had continued to fight on, despite such terror, was a kind of courage, he reflected earnestly. Courage, yes.

The fight at the crossing had been no exception. He had fought with the same will, driven by the same desire to be seen in the front rank, fighting alongside the rest of his men. No shirking behind the rear of the line, bellowing out weasel words of encouragement, and savage threats to those whose flinching cowardice was not protected by rank. To be singled out for execution, for a crime he had no part in, by something as blind and heedless of his virtues as a lottery, was the worst fate he could imagine.

The first raindrops pricked lightly at his skin and then pattered on the grass around him. A chill breeze stirred the long grass, and rustled the leafy boughs of the trees along the river bank. The young centurion eased himself over on to his side and curled into a ball to try to keep warm. The leather thongs binding his wrists and ankles had rubbed the flesh raw so that every movement was painful. He tried to keep still, and closed his eyes, even though this was his last night in this world. Cato had often thought that imminent death would make him want to be aware of even the smallest detail around him, to seize each last measure of delight in life.

'Seize the day,' he muttered, and then gave a small bitter laugh. 'Bollocks.'

There was no poignant appreciation of the world on his senses, no thrill of life, just a smouldering anger at the injustice of it all, and a hatred for Centurion Maximius so intense that he could feel it burning through his veins. Maximius would live on, free to redeem himself eventually for his failure at the river crossing, while Cato would be ferried across an altogether different river, never to return, never to prove himself innocent of the charge for which he was being executed.