Cato and Diodorus hurried towards the marine standing beside the mast. He stood aside and revealed a thin, sunburned figure, naked save for a soiled loincloth. At first Cato thought the man had thrown his arms up, but then he saw the broad black head of the iron nail that had been driven through his palms into the wood, pinning him upright, high enough so that he could not fully stand on the deck and had to carry his weight on his toes and the balls of his feet. A faint groan issued from the man’s mouth and his breathing was shallow and laboured.

‘Get him down!’ Cato ordered. He turned towards the Sobek and shouted, ‘Send the surgeon over!’

While two marines supported the man’s weight, a third grasped the head of the nail and began to work it free. The man gasped and cried out. His eyes, bloodshot and rolling up, flickered open. It seemed to take a long time to get the nail out of the mast and then the man collapsed into the arms of the marines.

‘Lay him down.’ Cato gestured to the nearest marine. ‘Give me your canteen. You and the others, search the ship for any other survivors.’

He leaned over the man as he pulled the stopper from the canteen, wincing as he saw the cracked and bloody lips. Slipping one hand behind the man’s head, Cato eased it up and poured a little water over the face. The lips smacked as they felt the water and there was a groan of relief as the liquid trickled inside his parched mouth. Cato fed him some more sips and stopped when he choked and coughed, spluttering as he turned his face aside.

‘Thank . . . you,’ he croaked weakly.

‘What happened here?’ asked Cato. ‘Who attacked you?’

The man’s swollen tongue licked his cracked lips and he winced painfully before he made his reply. ‘Romans . . .’

Cato exchanged a glance with Diodorus. ‘Romans? Are you certain?’

A shadow passed over the deck and Cato looked up to see the mast of the Ibis as Macro’s ship drew alongside. An instant later there was a dull thud as the ships nudged against each other. Then the sound of boots landing on the deck. Cato looked up and saw his friend. ‘Over here, Macro!’

Macro strode over, glancing round at the deck. ‘Looks like they had quite a battle.’

‘More of a massacre, I think. But we found this one alive.’ Cato gestured towards the torn flesh of the man’s hands. ‘Nailed to the mast.’

Macro let out a low whistle. ‘Nasty. Why would they do that?’

‘I can guess. They wanted to leave a witness behind. Someone who might live long enough to report what happened.’