'Yes, my lord.'

'Well, there have been enough of those. Don't give up yet. Put your mind to it.' There was desperation in his voice. 'And go to Lincoln's Inn. They'll maybe tell you things they won't tell my men. Search Marchamount's rooms.'

'Give me until Wednesday, my lord. I will do what I can. Do not tell the king till then.'

'Have you some lead?' His eyes bored into mine. I swallowed.

'I – no. But I will think, as you ask.'

He looked at me hard for another long moment, then turned back to his desk. 'Go then,' he said. 'God's death, Grey will bury me in papers.'

His resigned, almost gentle manner so surprised me that I stood there a moment, fighting a sudden urge to tell him I had found some Greek Fire and given it to Guy. I realized that my old loyalty to him was not quite dead, after all. Barak motioned to the door and, to my surprise, I heard footsteps scurrying away as he opened it. We stepped out to see Grey sitting down at his desk, his face flustered.

Barak grinned. 'Been eavesdropping, master secretary?'

He did not reply, but reddened.

'Leave him, Barak,' I said. I thought: Grey is terrified of what may be about to happen. He is right to be. And I have found some Greek Fire and hidden it from Cromwell. For a moment I felt faint again.

BARAK AND I SAT on the steps of Westminster Hall, each deep in gloomy thought.

'I expected he'd be furious,' I said, 'but he seems – almost resigned.'

'He knows what will happen if he has to tell the king Greek Fire is lost,' he said quietly.

'What in God's name has happened to Marchamount? Is he villain or victim?'

Barak shrugged despairingly. 'Jesu knows. I'll try again for news of Toky and Wright, but I fear I'll find nothing. I think some of my contacts are being paid to keep their mouths shut.'

'Isn't it strange how, every time we approach the truth, the person we seek is killed? Almost as though someone was telling the enemy of our movements. And who took those books from Lincoln's Inn, and frightened the librarian?'

He frowned. 'I don't see that. It was Madam Neller that betrayed Bathsheba and her brother. The founder disappeared long before we got there. And Marchamount may have fled of his own accord.'

I nodded. 'That would mean he was the one behind it all. It starts to look that way.'

'It does. But we need more evidence.'

'We could go through his rooms.'

'I must look for Toky first. I'll come with you later.'

I stood up. 'Very well.' I looked at him. 'Be careful. It could be dangerous for you.'

'I can look after myself.' He stood and dusted himself down. 'It's letting my master down, that's what's hard.'

'There's still time,' I said. 'I'll meet you at home later.' I took a deep breath. 'My arm hurts.'

'My shoulder's better. He knows a few things, that old Moor.' He stood looking out over the river a moment. I followed his gaze. Something bright and fiery on the water made me start for a moment, then I saw it was only a ray of sunlight falling through the light cloud, flecking the little waves tossed up by the wind a flickering bright yellow.

I COULD SEE NOBODY through the window of Guy's shop and feared he had gone out, but when I knocked footsteps sounded in the furthest reaches of the building and he appeared. He looked tired.

'You got my message, Matthew?'

'Yes.' I slipped inside and he closed the door.

'How is Elizabeth?' he asked. 'I am going to visit her later.'

'Better. In body at least.' Briefly, I told him what we had found down the well and of my conversation with her. He gave me a penetrating look.

'And you intend to confront the family?'

'Yes. And it must be very soon. Elizabeth is back before Forbizer on Thursday.'

'Be careful,' he said. 'There is something of pure evil in this story.'

'I know.' Suddenly I felt faint again and I sat down quickly in a chair.

'What is the matter?'

'A moment's faintness. The heat.'

He came and looked down at me. 'Have you had this before?'

'Yesterday.'

'You have taken on more than a man can reasonably bear.'

'Barak seems able to manage.'

Guy smiled. 'I talked with Master Barak when he brought you here after the fire. He improves somewhat on acquaintance.'

'Ay, he said you gave him something to put in the dogs' meat.'

'Yes. But do not compare yourself to him. He is a man of the streets, a lot younger than you. And he has an adventurer's disposition.'

'And a straight back.'

'That need not trouble you so much if you would do my exercises. I suppose you will say you have had no time.'

'God's truth, I haven't.' I looked him in the eye. 'All my leads have run into the ground. And one of our suspects has disappeared, the lawyer Marchamount. We don't know yet if he's the man behind it all or if he's been killed like the others. Guy, the one thing I have left is that Greek Fire.'

He nodded. 'Come through to my workshop.'

I followed him to a back room. With its bottles and retorts full of strange fluids, its bench and complex apparatus of oddly shaped distilling glasses, it reminded me of Sepultus Gristwood's workshop.

'I did not know you had such a place here, Guy.'

'Experimenting with distillation interests me.' He smiled. 'I keep it quiet in case the locals say I'm a magician.'

I saw the pewter jar of Greek Fire on the windowsill. Guy pointed a finger at one wall and I saw that it was blackened as the Gristwoods' yard had been. 'Some of the stuff caught fire yesterday while I was trying to distil it. Filled the place with filthy black smoke. Luckily I used only a very little.'

I stared at the jar, then turned to him. 'What is it, Guy?' I asked passionately. 'What is it made of?'

He shook his head. 'I do not know, Matthew. In a way I am glad, for I would not wish anyone to have this weapon.' He spread his hands. 'I have distilled it, tried to see how it reacts with other substances, tried to find some clue to what it is. But it has defeated me.'

I felt my heart sink, though at the same time a part of me was also relieved.

'I know some reputable alchemists,' he said. 'They might be able to help, given time.'

I shook my head. 'We have no time. And I would not trust anyone but you to keep this secret.'

He spread his hands. 'Then I am sorry.'

'You did your best.' I went and opened the jar, looking at the brown stuff inside. 'What are you?' I whispered.

'All I can say is it resembles no substance I have ever seen before. Certainly its composition is nothing like that Polish stuff.'

I thought a moment. 'If you cannot work it out, how could Sepultus? By all accounts he was a rogue and no true scholar.'

'He had months to experiment. Did you not say there were six months between the stuff's discovery and his approach to Cromwell?'

'Yes.'

'And the formula may say what the constituent elements are. At least tell him enough to give him more of a start than we have. It must all come down to earth and air, fire and water in the end.' He spread his hands. 'But in which of the millions of possible combinations?'

I nodded sadly. 'Thank you for trying. You know, you are the only man I feel I can always rely on to give me true answers, solve my problems. Perhaps I expect too much.'

'Perhaps you do,' Guy said. 'I am only frail human clay, for all people think I have strange powers to go with my strange looks.'

'Perhaps I should not have asked you to deal with something so devilish.'

He looked at me seriously. 'What will you do now?'

'I don't know what is left. Cromwell asked me to think.'