His own father would have to sentence him to death. Maybe that was the only possible outcome for a member of the House of Atreos.

Maybe that was where everything had been tending towards, over all these centuries. The bloodied knife, making its way home.

So many had been killed before him by their own kin. He would be killed too, and Penthilos would take his place. Penthilos would end the cycle. There was nobody else.

Tisamenos placed his hands on the stone slabs of the walls. The kinghouse would help him. It had to.

His mind became still, a brief space in which he imagined the outline of his cell. Then an overwhelming clanging filled his skull.

The kinghouse was in uproar. He could not focus.

He tried again, but the clamour was too much, like a thousand smiths banging their hammers on vast anvils. It was too much. He knelt, hands tight over his ears, until the noise seemed to become the world.

A voice startled him, warm and lively. ‘What have we got here then?’ He opened his eyes and saw a young, cheerful-looking guard. He must have come in whilst Tisamenos was asleep. The handsome guard took his helmet off, revealing an unruly mop of springy, curly black hair, so black it gleamed. He winked at Tisamenos, and sat down on his haunches, sword clinking.

The cell seemed lighter. Tisamenos managed to sit up. The guard smiled at him, so infectiously that Tisamenos couldn’t help smiling back. His eyes were shining with humour.

‘Here,’ murmured the guard, and passed a goblet to him. Tisamenos took it, noting that it was unusually rich for a guard to possess, and gratefully put it to his lips. It contained a strong draught of wine and honey. The young guard grinned widely as Tisamenos drank deeply. ‘My mother makes that mixture. She always says to me, “Demos, that’ll put curls in your hair.” ’

‘It certainly does,’ said Tisamenos, feeling stronger. ‘I give you my most heartfelt thanks. I don’t think I know you. I have not seen you in the kinghouse before.’ He spoke formally, realising how stupid it was, but he wanted to honour Demos and show him that even if he was in a cell, he was still the son of Orestes.

‘You do know me,’ said Demos, showing beautiful, even white teeth. ‘I’ve been here a long time. Always, in a sense.’ He fingered the hem of his tunic, and polished his nails on his sleeve. ‘But that’s beside the point.’

Demos’s voice took on a confidential tone. He looked over his shoulder, then back at him. ‘She played a trick on you. Now you need to play a trick on her. Use what you have.’ He tapped Tisamenos’s head, then nodded once, as if in confirmation of the statement, and sprang upwards with the agility of a hare.