‘And the package? From our ally, Themistocles?’ Xerxes asked. The king could hardly contain his hope, no matter how illogical. He had felt a terrible vice closing on his head. He longed for deliverance from that pressure, for a clear path to follow.

‘It is, Majesty,’ Mardonius replied, his tone colourless as the night. The general handed a single sheet of papyrus to the king’s herald. Without being asked, one of the guards fetched a torch and held it at a careful distance so that light fell on the page. The translator’s fingers trembled as he began to speak.

‘“To His Majesty, Great King of Persia, Xerxes, ruler of all … know that my fleet captains have grown bold with successes today. I had hoped to see your ships block the strait before dark, so that I could ask for surrender and be honoured for my service. Instead, my people are talking of cutting off your retreat, of holding you here. They describe a great bridge of ships and say how easy it would be to …”’ the herald wiped sweat from his forehead as he peered at the page, ‘“to destroy such a thing and strand your army in Greece without supply. Perhaps a hundred captains wish to break out this very night and head east to that end. Majesty, I speak as your most loyal servant. My life is forfeit if they know I warned you. It is my hope that you will use what I have said to bring peace. I hope then you will remember who stood as a friend of your noble house and the empire. Themistocles.”’

Xerxes felt his stomach flutter as the translator read. At the end, the silence was profound.

‘Can they do it?’ he demanded. ‘Can they break my bridge of ships?’

Mardonius considered only for a moment. It was a bold move, like locking a door behind a violent man, trapping him in the room with you. It seemed the Greeks were more confident than he had understood. Mardonius closed his eyes briefly before speaking, feeling ill.

‘It is, Majesty. We left a baivarabam of ten thousand men to guard the bridge – but yes, if the Greeks took a hundred of their galleys, they could break it. We saw once before what happens when a storm lashes the bound ships. If just one comes apart, the rest flail like a whip. It would not take much to smash the sea-road.’