Helena obviously remembered exactly what I was talking about. 'You mean, the night you came back to the tent tipsy, brought home by Tranio, who annoyed us by hanging about and grovelling in the play box?'

'Remember he seemed frantic? He said Heliodorus had borrowed something, something Tranio failed to find. I think you were lying on it, my darling.'

'Yes, I wondered about that.' She smiled. 'Since he insisted that his lost object wasn't a scroll, I didn't feel I needed to mention it.'

I thought of Grumio telling me that ridiculous story about his lost ring with the blue stone! I knew now I had been right to disbelieve the tale. You would never hope to find so small an item in a big trunk crammed with many sets of scrolls. They had both lied to me about it, but the famous gambling pledge that Tranio gave away to Heliodorus should have been obvious to me long ago.

'Helena, do you realise what all this has been about?'

'Maybe.' Sometimes she irritated me. She liked to go her own way, and refused to see that I knew best.

'Don't mess about. I'm the man of the household: answer me!' Naturally, as a good Roman male, I had fixed ideas about women's role in society. Naturally, Helena knew I was wrong. She hooted with laughter. So much for patriarchal power.

She relented quietly. This was a serious situation, after all. 'I think I understand the dispute now. I had the clue all along.'

'The scroll,' I said. 'Your bedtime read is Grumio's inherited humour collection. His prized family asset; his talisman; his treasure.'

Helena drew a deep breath. 'So this is why Tranio behaves so oddly sometimes. He blames himself because he pledged it to Heliodorus.'

'And this is why Heliodorus died: he refused to hand it back.'

'One of the clowns killed him because of that, Marcus?'

They must both have argued with the playwright about it. I think that's why Grumio went to see him the day he stopped Heliodorus raping Byrria; she said she overheard them arguing about a scroll. Various people have told me that Tranio tackled the bastard as well. Grumio must have been going spare, and when Tranio realised just what he had done, he must have felt pretty agitated too.'

'So what happened at Petra? One of them went up the mountain to make another attempt to persuade Heliodorus to relinquish it, actually meaning to kill him?'

'Maybe not. Maybe things just went too far. I don't know whether what happened was planned, and if so whether both clowns were in on it. At Petra they were supposed to have drunk themselves unconscious in their rented room while Heliodorus was being killed. One of them obviously didn't. Is the other lying absolutely, or was he really made completely drunk by his roommate so that he passed out and never knew his companion had left the room? If so, and the first deliberately held back from drinking to prepare an alibi – '

'Then that's premeditation!' Helena exclaimed.

It seemed to me that if Grumio were the culprit but Tranio still regretted giving away the pledge, that could make Tranio willingly cover for him at Petra, and might explain Tranio's feeble attempt to make Afrania lie about his own alibi at Gerasa. But Grumio had a whole crowd of people to vouch for him when Ione was killed. Had Afrania been lying to me all along, and was Tranio Ione's killer? If so, were events at Petra the opposite way around? Did Tranio kill Heliodorus, and Grumio cover up?

'This is all becoming clearer, but the motive seems extravagant.' Helena was looking worried for other reasons. 'Marcus, you're a creative artist.' She said it entirely without irony. 'Would you be so upset by losing a batch of rather old material that you would go so far as to kill for it?'

'Depends,' I replied slowly. 'If I had a volatile temperament. If the material was my livelihood. If it was mine by rights. And especially if the person who now possessed it was an evil-mannered scribe who would be bound to gloat about using my precious material: We'll have to test the theory.'

'There's not going to be much opportunity.'

Suddenly I reached the end of my tolerance. 'Ah cobnuts, sweetheart! It's my debut tonight; I don't even want to think about this any more. Everything will be all right.'

Everything. My ghost play; Sophrona; finding the killer; everything. Sometimes, even without grounds for optimism, I just knew.

Helena was in a more sober mood. 'Don't joke about it. It's too grave a subject. You and I never make light of death.'

'Or life,' I said.

I had rolled to pin her beneath me, carefully keeping her bandaged arm free of my weight. I held her face between my hands while I studied it. Thinner and quieter since her illness, but still full of searching intelligence. Strong, quizzical eyebrows; fine bones; adorable mouth; eyes so dark brown and solemn they were making me ferment. I had always loved her being serious. I loved the madcap thought that I had made a serious woman care for me. And I loved that irresistible glint of laughter, so rarely shared with others, whenever Helena's eyes met mine privately.

'Oh my love. I'm so glad you've come back to me. I had thought I was losing you – '

'I was here.' Her fingers traced the line of my cheek, while I turned my head to brush the soft skin of her wrist with my lips. 'I knew all that you were doing for me.'

Now that I could bear to think about what had happened with the scorpion, I remembered how one night when she had been tossing with fever she had suddenly exclaimed in a clear voice, ' Oh Marcus?, as if I had entered a room and rescued her from some bad dream. Straight after that she had slept more quietly. When I told her about it now, she was unable to recollect the dream, but she smiled. She was beautiful when she smiled that way, looking up at me.

'I love you,' Helena whispered suddenly. There was a special note in her voice. The moment when the mood between us altered had been imperceptible. We knew each other so well it took only the faintest change of tone, a slightly increased tension in our bodies lying together. Now, without drama or prevarication, we were both wanting to make love.

Everywhere outside was quiet. The actors were still rehearsing, so were Thalia and the circus performers. Within the tent a couple of flies with no sense of discretion were buzzing about against the hot goatskin roof. Everything else lay still. Almost everything, anyway.

'I love you too:" I had told her that, but for a girl with exceptional qualities I did not mind repeating myself.

This time I did not have to be asked to kiss her, and every atom of my concentration was being applied. It was the moment to find the jar of alum wax. We both knew it. Neither of us wanted to disturb the deep intimacy of the moment; neither of us wanted to draw apart. Our eyes met, silently consulting; silently rejecting the idea.

We knew each other very well. Well enough to take a risk.