There was a gasp from the track, a horse whinnied, a man drew breath to shout and then there was the sound of a body thudding to the ground. By the time Cato had risen to his knees it was all over. Twenty feet away Bedriacus was easing one of the scouts from the back of his horse. The man was already dead: the handle of a knife protruding from under his chin, the blade punched up into his brain. His companion rustled in the grass for a moment, blood pumping from his slashed throat and spraying crimson droplets over the surrounding tussocks. Then he was still.

Bedriacus yanked his blade free of the scout’s skull and wiped it clean on the man’s long hair as he looked up at his centurion. Cato nodded his approval and pointed at the horses, nervous and a bit flighty at the shock of the hunter’s sudden appearance. Moving slowly towards them Bedriacus whispered softly and gently ran his fingers across their silken flanks until his grip tightened on the reins.

‘To the rear,’ Cato whispered in Celtic.

The hunter nodded, clicked his tongue and led the animals down the track between the hidden centuries, and set them loose. Whatever magic he had worked on the beasts continued to have its effect and they calmly tore at the lush growth of grass beside the track. Bedriacus padded back to Cato to retrieve the wolf standard and took position beside his commander.

The rumble of chariot wheels on the other side of the ford was clearly audible now, and the moment Cato heard the first splashes he turned down the slope and, cupping his hands, called as loudly as he dared, ‘Cohort! Stand up!’

Nearly five hundred men appeared from the long grass, silently rising to their feet, oval auxiliary shields tightly gripped. The splashing noises from the ford grew in volume as the infantry started across the river. They could no longer hear the noise of the chariots. They must have stopped, as Cato had guessed they would. The ford would make a perfect spot for the Durotrigans to camp for the night; largely hidden by the surrounding landscape, on dry ground with a river to water the horses and men.

‘Draw swords! Make ready to advance!’

Cato turned back to Bedriacus. ‘Stay here.’

The hunter nodded and Cato crept up the track, stretching his neck to catch sight of the situation at the ford. Half of the Durotrigan column was across. The chariot drivers were already unhitching their horses, while their warriors stood together at the edge of the river, clustered around a short, bull-like man with blond pigtails, who was evidently giving them their orders for the evening. As he looked round at his men, he suddenly froze, staring straight up the track in Cato’s direction. He had seen the scarlet crest on the centurion’s helmet, brilliantly illuminated by the rays of the setting sun.