The trail ran straight the last few miles, and when they came to the spot it was easy to see in his mind’s eye what had happened. They had unharnessed the two ponies from the chariot and then burned the car. The remains were scorched a deep black by a great heat, for they must have used oil to get the wood and leather to burn in all this rain. The ponies lay dead, throats cut and made to lie down on either side of the pyre.

‘The Legate Marcellus was right,’ Crispinus said, patting his horse to calm it as it tried to pull away. ‘A prophet cannot fail.’

The Stallion’s corpse swung gently in the breeze, suspended from one of the main branches of the yew tree. Ferox imagined Acco the druid supervising, probably placing the noose around the priest’s head himself, then watching as the others hauled him up and made the rope fast. The naked priest would have jerked and twitched, struggling for breath, choking slowly as his own weight dragged his body down. They had cut him about the body, cut him time and again, and Ferox saw a broken flint blade on the ground, which meant that they had not used ordinary knives. A great scar ran across his stomach, sewn up and starting to heal a little, which was the wound the centurion had given him during the battle. It did not look as if it would have proved fatal. All the other cuts were neater, less deep, and the rain had fallen, washing away the blood, so all that was left was slice after slice cut into his white skin. It would have taken a long time and traces around his lips told Ferox that the man had been given poison as well. The triple death, the sacred death of a willing victim sacrificed to appease the anger of the gods.

Flaccus gave a nervous laugh. ‘These Britons really don’t like failures.’

Ferox did not bother to answer. The Romans would never understand.

Flaccus jumped down. ‘You men,’ he ordered the escort. ‘Help me cut this fellow down. My Lord Crispinus, perhaps you would like to do the honours and take his head?’

The tribune seemed surprised, but realised that there would be something for him to boast about and shock his friends with when he returned to Rome, so got down.

Ferox gestured to Vindex to dismount as well. ‘Do you trust me?’ he whispered to the Brigantian.

‘No.’

‘Then just do what I ask. Have your blade ready. When I look away and say that I’m expecting someone to join us, that will be the signal.’

Crispinus had thrown his cloak back to get at his sword. He drew it, just as one of the legionaries rode over to the tree and sawed through the rope. The corpse thumped on to the soggy ground and somehow looked even whiter.