And then I realized that blinkered thinking of another sort had blinded me to the truth of what had happened at Scarnsea. I had bound myself to a web of assumptions about how the world worked, but remove one of those and it was as though a mirror of clear glass were substituted for a distorting one. My jaw dropped open. I realized who had killed Singleton and why and, that step taken, all fell into place. And I realized I had little time. For a few moments more I sat with my mouth open, breathing heavily. Then I roused myself and rode as fast as the nag would go, back to the place where, if I was right, the last piece of the puzzle lay: the Tower.

It was dark by the time I rode over the moat again, and Tower Green was lit by flaming torches. I almost ran into the Great Hall and made my way again to Master Oldknoll's office. He was still there, carefully transferring information from one paper to another.

'Master Shardlake! I trust you've had a profitable day. More than mine, at least.'

'I must speak urgently to the gaoler in charge of the dungeons. Can you take me straight there? I've no time to wander round trying to find him.'

He read the importance of the matter from my face. 'I'll take you now.' He picked up a great bunch of keys and led me off, taking a torch from a passing soldier. As we passed through the Great Hall he asked if I had ever been to the dungeons before.

'Never, I'm glad to say.'

'They are grim places. And I've never known them busier.'

'Yes. I wonder what we are coming to.'

'A country full of godless crime, that's what. Papists and mad gospellers. We should hang them all.'

He led me down a narrow spiral staircase. The air became sharp with damp. There was green slime on the walls, fat beads of water running down it like sweat. We were below the level of the river now.

At the bottom was an iron gate, through which I saw a torchlit underground chamber where a little group of men stood round a paper-strewn table. A guard in Tower livery came over to us and Oldknoll addressed him through the bars.

'I have one of the vicar general's commissioners here, he needs to see Chief Gaoler Hodges at once.'

The guard opened the gate. 'Over there, sir. He's very busy; we've taken in a load of Anabaptist suspects today.' He led us over to the table, where a tall thin man stood checking papers with another guard. On both sides of the chamber there were heavy wooden doors with barred windows, from one of which a loud voice issued, calling out verses from the Bible.

'Behold I am against them saith the Lord of Hosts, and I will burn the chariots and the sword shall devour thy young lions…'

The gaoler raised his head. 'Shut your mouth! Do you want a whipping?' The voice subsided and he turned to me, bowing. 'Your pardon, sir, I am trying to sort the delations for all these new prisoners. Some of them are to go before Lord Cromwell for interrogation tomorrow, I don't want to send him the wrong ones.'

'I need information about a prisoner who was here eighteen months ago,' I said. 'Do you remember Mark Smeaton?'

He raised his eyebrows. 'I'm not likely to forget that time, sir. The queen of England in the Tower.' He paused, remembering. 'Yes, Smeaton was down here the night before his execution. We had instructions to separate him from the other prisoners, he was to have some visitors.'

I nodded. 'Yes, Robin Singleton came to make sure he was keeping to his confession. And there were other visitors. Would they be recorded?'

The gaoler exchanged a look with Oldknoll and laughed. 'Oh yes, sir. Everything's recorded nowadays, isn't it, Thomas?'

'At least twice.'

The gaoler sent one of his men off, and a few minutes later he returned with a heavy log book. The gaoler opened it.

'May 1536, the sixteenth.' He ran his finger down the page. 'Yes, Smeaton was in the cell that mayhemmer's in.' He nodded at the door from which the declamations had issued; silent now, only darkness visible through the bars.

'His visitors?' I asked impatiently, coming to peer over his shoulder. He shrank away a little as he bent once more to his book. Perhaps a hunchback had once brought him bad luck.

'See, there's Singleton, brought in at six. Another, marked "relative" at seven and then "priest" at eight. That's the Tower priest, Brother Martin, come to confess him before his execution. A pox on that Fletcher, I've told him always to put in the names.'

I ran my finger down the page, looking at the other prisoners' names. 'Jerome Wentworth called Jerome of London, monk of the London Charterhouse. Yes, he's here too. But I need to know about that relative, Master Hodges, most urgently. Who is this Fletcher, one of your guards?'

'Aye, and he doesn't like the paperwork. His writing's not good.'

'Is he on duty?'

'No, sir, he's had leave for his father's funeral up in Essex. He won't be back till tomorrow afternoon.'

'He comes on duty then?'

'At one.'

I bit my finger. 'I will be at sea by then. Give me paper and a pen.'

I quickly scribbled two notes and handed them to Hodges.

'This one asks Fletcher to tell me all he remembers of that visitor, everything. You will impress on him that the information is vital, and if he can't write the answer get someone else to. When he's done, I want the answer taken at once to Lord Cromwell's office with this other letter. It asks him to provide his fastest rider, to bring Fletcher's answer to me down at Scarnsea. The roads will be hell itself if this snow's melting, but a good man might be able to reach me by the time my boat gets in.'

'I'll take it to Lord Cromwell myself, Master Shardlake,' Oldknoll said. 'I'll be glad to get out in the air.'

'I'm sorry about Fletcher,' Hodges said. 'Only there's so much paperwork now, sometimes it doesn't get done properly.'

'Just make sure I have that answer, Master Hodges.'

I turned away, and Oldknoll led me out of the dungeons. As we mounted the stairs we heard the man in Smeaton's cell shouting again: a litany of garbled quotations from the Bible, cut off with a sharp crack and a yell.

CHAPTER 30

I was lucky with the winds on the return journey; once out at sea the mist faded and the boat was driven down the Channel by a light south-east wind. The temperature had risen several degrees; after the biting cold of the last week it felt almost warm. The boatman had a cargo of finished cloth and iron tools to bring back, and was in a more cheerful mood.

As we approached land on the evening of the second day, I saw the coastline, wreathed in light mist. My heart quickened; we were nearly there. I had spent much time on the voyage thinking; what I did next depended on whether the messenger from London had arrived. And it was time for another talk with Jerome. Now a thought I had tried to suppress these last couple of days came to the front of my mind: were Mark and Alice still safe?

The mist made it hard to see as we navigated the channel through the marsh to Scarnsea wharf. The boatman asked diffidently if I could take a pole and push the boat from the banks if we came too close and I agreed. Once or twice it almost stuck in the thick, glutinous mud through which little rivulets of melting snow were running. I was glad when at last we reached the wharf. The boatman helped me onto dry land with thanks for my help, and perhaps ended by thinking less badly of at least one reforming heretic.

I made my way at once to Copynger's house. He was just sitting down to supper with his wife and children and invited me to join his board, but I said I must get back. He led me to his comfortable study.