Joseph looked at me, then said softly, 'I become angered with her too.'

I sighed. 'My apothecary should be here soon.'

'You are generous, sir,' Joseph said. 'How much-'

I raised a hand. 'No, Joseph, we can discuss that later. Barak, you look exhausted. You should go home.'

'I can stay,' he said. 'I'd like to see whether the Old Moor can help her.'

It was strange, even touching, to see how absorbed he had become in Elizabeth's fate. Yet I did not want him here when Guy came; I had secreted the pewter jar of Greek Fire in a pocket of my robe. 'No, go,' I said sharply. 'I don't want you risking gaol fever, I need you fit.'

He nodded reluctantly and went out. I clutched at the jar of Greek Fire as Joseph and I stood in silence, listening to Elizabeth's fevered breathing.

GUY ARRIVED an hour later. The gaoler himself fetched him up, goggling at his brown face till I bade him sharply to be gone. I introduced Guy to Joseph, who likewise stared at him in surprise, although Guy affected not to notice.

'So this is the poor girl whose travails have worried you so,' he said to me.

'Yes.' I told him of the onset of her fever. He looked at her for a long moment.

'I don't think it's gaol fever,' he said at length. 'The fever would be higher. I'm not sure what it is. It would help to see her urine. Does she have a pisspot?'

'She was left to piss on the straw in the Hole.'

He shook his head. 'Then I will give her something to try and stop her burning up, and it would be good if she were to be washed and that filthy dress taken off her.'

Joseph blushed. 'Sir, it would hardly be proper for me to see her unclothed-'

'I will do it, if you like. In my trade a naked body is hardly a new sight. Could you buy her a shift tomorrow and bring it here?'

'Yes. Yes, I will.'

As we watched Elizabeth stirred and made a little moan, then lay back again. Guy shook his head. 'What pain and anger there are in that face, even while her mind sleeps.'

'Is there any hope, sir?' Joseph asked.

'I do not know,' Guy said frankly. 'This may be one of those cases where much depends on the sufferer's will to live.'

'Then she will surely die,' he said.

'Come, we do not know that.' Guy smiled gently. 'And now, if you will leave me, I will wash her.'

Joseph and I waited outside while Guy carried out his task. 'I cannot help being angered, sir,' he said. 'But I love her; for all she has put me through I still love her.'

I touched his shoulder. 'That is very plain, Joseph.'

At length Guy called us back. He had laid Elizabeth under the blanket and lit some sort of oil in a lamp, which made a sweet smell in the room. A cloth, black with dirt, floated in the ewer. Elizabeth's face was clean, the first time I had seen it so.

'She is pretty,' I said. 'How sad she should come to this.'

'Sad whether she is pretty or ugly,' Guy said.

'What is that smell?' Joseph asked.

'An infusion of lemons.' Guy smiled. 'Sometimes when a soul is in pain a foul or cruel environment can drive it deeper into darkness. Thus light and cleanliness and soft airs may help lift her spirit, perhaps even reach it while she lies unconscious.' He shrugged self-deprecatingly. 'So I think, at least.' He looked at us. 'You both look exhausted. You should sleep. I will stay with her till morning if you wish.'

'I could not ask that-' Joseph protested.

'Please, I would be happy to.'

'I would stay a little too,' I said. 'I have something else I wish to discuss with you.'

Joseph left, with fulsome thanks, his weary footsteps clattering down the stairs.

'Thank you for this, Guy.' I said.

'It is all right. I confess I am intrigued. This is a strange condition.'

'I have something even more intriguing,' I said. I reached into my pocket and took out the cloth with the pewter jar in it. 'This, I believe, is Greek Fire. No one else knows I have it.' I unwrapped the jar and laid it on the table, first putting the oil lamp on the floor. 'Don't bring the candle near, Guy. I fear it may take light.'

He examined the stuff as best he could in the weak light, rubbing the dark liquid between his fingers, sniffing it with a look of distaste. 'So this is it,' he said. 'Dark Fire.' I had never seen his face more serious.

'Ay. I wondered how fire could be dark; I see now they meant the liquid was black.'

'Perhaps they also meant the darkness it could bring to men's lives.'

'Perhaps. They called it the devil's tears as well in the old books.' I told him how I had found it at Smithfield, how narrowly it had escaped Rich's clutches. 'Take it. Will you examine it tomorrow?'

'On the terms I gave you. I will do nothing to help Cromwell use it.'

'Agreed.'

He shook his head. 'You would be in serious trouble, Matthew, if he were to find you had given this to me instead of to him.'

I smiled nervously. 'Then we must be sure he does not find out.' I shook my head. 'Yet I cannot help thinking-' I hesitated – 'Cromwell has done many evil things. But at least he has a vision of a Christian commonwealth, while Norfolk would take England back to superstition and darkness.'

'A Christian commonwealth? Is such a thing even possible in this fallen world? Surely the annals of the last thousand years show it is not. That is why many like me chose to escape to the cloister before that was forbidden.'

'Yes, the old Church always believed the sinful world was heading towards a final cataclysm; nothing man did could make any difference. And that excused much oppression.'

'You would need fierce measures to make a perfect commonwealth. If you were to end poverty and beggary you'd need to squeeze their wealth from the rich, for example.'

'Sometimes I think that would be a good thing.'

'Now you sound like an Anabaptist.'

I laughed. 'No, just a puzzled old lawyer.'

He looked at me seriously. 'But ending social injustice is not Cromwell's first priority, you know that. What matters to him is the Protestant faith and he would use Greek Fire to cut a terrible swathe to achieve that if he could.'

I nodded sadly. 'Yes, you are right. He cannot be trusted with it. No one can.'

Guy looked relieved. 'Thank Christ you see that.' He looked at the pewter pot, then carefully put it in his pocket. 'I will let you know as soon as I have something to tell you.'

'Thank you. Tomorrow if you can – there are only five days now till the demonstration before the king.' I sighed. 'On the day Elizabeth goes back to court.'

As though in response to her name Elizabeth stirred, her legs moving beneath the blanket. We turned to her. 'Sarah,' she muttered again, then, 'that evil boy. The evil boy.' And then her eyes fluttered open and she looked at us uncomprehendingly.

Guy leant over her. 'Miss Wentworth, you are in a clean room in the prison. You have a fever. I am Guy Malton, an apothecary. Your good uncle and Master Shardlake had you brought here.'

I leant over her. Her eyes were heavy with fever but she seemed fully conscious. Knowing this was a chance that might never come again, I said slowly, 'We are still trying to find the truth, Elizabeth. We are trying to save you. I know there is something in the well at your uncle's house-'

She seemed to shrink back. 'The death of God,' she whispered. 'The death of God.'

'What?' I asked, but her eyes closed again. I made to shake her but Guy held my arm.

'Do not distress her further.'

'But – what did she mean? The death of God? God's death is a common curse, but-'

He looked at me seriously. 'The death of God is despair. When I was a monk sometimes one of my brethren would lose his faith, succumb to despair. Usually they came back to faith, but until they did-' he shook his head – 'it felt as though God was dead.'