Father and son parted. Orestes, standing back a pace, stroked Tisamenos’s cheek, and paused when he came to the stone part of his head. A frown passed over his features.

‘What’s this?’

‘I have a lot to tell you, Father,’ said Tisamenos. There was a note of pride in his voice, but also a quiet respect. It seemed to Elissa that Orestes was looking at his son with new eyes.

‘But first we must do what we came here for,’ Silvius cut in, stepping forwards and taking the chain from his neck. ‘What is in the box?’ His eyes were glistening brightly, and he looked feverish and flushed.

‘I do not know. But I know that it is for you.’

Orestes solemnly opened the lid, which shone now with a white light.

Elissa edged forwards to look into it and for a blissful moment she felt the beauty of Apollo’s light. She heard Orestes gasp, and then her eyes adjusted.

There it was.

Looking like an ordinary wooden thing, feathered by an expert fletcher, yet thrumming with divine power, was the other half of Apollo’s arrow.

Elissa’s heart quickened. The king held out his hand, but Silvius shook his head. ‘No. I will place it back with the Shaft.’

There was a perceptible shift in the air as the two caskets were positioned next to each other, and a glowing arc of white light sprang from one to the other.

Elissa sensed another presence in the room, a joyous one which charged the atmosphere.

There, lit by the whiteness, apparently as yet unseen by the others, was the god Hermes.

He had slipped into her sight in the curious way that gods had, as if he had always been there but she just hadn’t noticed, with his warm smile and glossy black, curly hair. He was eating an apple rather studiedly, a quiver slung over his shoulder. The god swallowed the last bite of the apple, nodded mock gravely to Elissa and tossed away the core.

‘My lord Hermes!’ Orestes had seen him, and now the others were aware of him, his bright essence lighting up the clammy chamber. Silvius bowed his head, whilst Tisamenos gazed in wonder.

The god, without seeming to move through space, was now bending over the Arrowhead and the Shaft. ‘Such power,’ he murmured. Tenderly he lifted up the Arrowhead’s casket. Silvius flinched as he opened the lid. But of course Hermes did not ask for destruction, and instead stroked it with his finger.

‘A pretty thing.’ Hermes toyed with the Arrowhead, turning it up and down, admiring the sheen of colours rippling over it. ‘And now, I bring together what has been separated.’

Elissa felt a surge of Apollo’s clarity. She grabbed Silvius by the hand, and saw his face was lit with joy. Tisamenos was kneeling, and Orestes, awed by the presence of the god who had absolved him, was prostrate on the ground.