The monastery itself stood at right angles to the hospital, its high buildings dominating the square, although some of those had gone now. Here too a guard stood outside the gatehouse. I saw workmen were bringing out boxes and stacking them against the wall, where a group of blue-robed apprentices buzzed around them.

'Can't see Kytchyn anywhere,' Barak said. 'We'll have to ask the guard.'

We rode across the open space, where paths led between clumps of scrubby grass. There was one large patch of earth where no grass grew and the earth was mixed with blackened cinders; the site where heretics were burned. I remembered Lord Cromwell once telling me he longed to burn a papist using his own images for fuel and two years ago he had: a wooden saint had fed the pyre when Father Forest was burned there, suspended above the fire in chains to prolong his agony before ten thousand spectators. Forest had denied the king's supremacy over the Church, so legally he should have been executed as a traitor, not burned, but Cromwell could afford to ignore such niceties. I had not been there, but as I averted my eyes from the spot I could not help reflecting on that terrible death; the flames making the skin shrivel away, the blood beneath hissing as it dropped into the fire. I shook my head to clear it as I pulled Chancery to a halt before the gatehouse and dismounted.

I saw the boxes were full of bones, brown and ancient. A group of apprentices was delving inside them, casting pieces of tattered winding sheets onto the pavement, hauling out skulls and carefully scraping away the greenish moss that clung to some of them. The watchman, a huge fat fellow, watched indifferently. We tied the horses to a post. Barak went over to the watchman and nodded at the apprentices. 'God's teeth, what are they at?'

'Scraping off the grave moss. Sir Richard is clearing out the monks' graveyard.' The big man shrugged. 'The apothecaries say the moss on the skulls of the dead is good for the liver and they've sent their apprentices up here.' He delved in his pocket and pulled out a little golden trinket in the shape of a crescent. 'There's some strange things buried with them – this monk had been on the Crusades.' He winked. 'My little bonus for letting the boys scavenge.'

'We have business here,' I said. 'We are due to meet a Master Kytchyn.'

'Lord Cromwell's business,' Barak added.

The doorman nodded. 'The fellow you want is here already, I allowed him into the church.' He studied us closely, eyes alert with curiosity.

I walked up to the gateway. The guard hesitated a moment, then stepped aside and let us through.

The scene that met my eyes on the other side of the gatehouse made me stop dead. The nave of the great church had been pulled down, leaving only a gigantic pile of rubble from which spars of wood protruded. The north end of the church still stood and a huge wooden wall had been erected to seal it from the elements. Most of the neighbouring cloisters had been pulled down too, and the chapter house stripped of its lead. I could see beyond to the prior's house, the fine dwelling Sir Richard Rich had bought. Washing hung from lines in the back garden and three little girls ran and played among the flapping sheets, oddly incongruous amid the destruction. I had seen monastic houses brought down before – who had not in those days? – but not on this scale. A sinister quietness hung over the wreckage.

Barak laughed and scratched his head. 'Not much left, is there?'

'Where are the workmen?' I asked.

'They start late if it's Augmentations work. They know it's a good screw.'

I followed Barak as he picked his way through the rubble towards a door in the wooden barrier. I had a lifetime's contempt for these huge, rich monastic churches kept for the enjoyment of perhaps a dozen monks; when the purpose of the foundation was to serve a hospital the waste of resources seemed even more obscene. Yet as I followed Barak through the door, I had to admit that what was left of the interior of St Bartholomew's Church was magnificent. The walls soared a hundred and fifty feet in a series of pillared arches, richly painted in greens and ochres, up to a row of stained-glass windows. Because of the wooden barrier at the south end, what remained of the interior was gloomy, but I could see that the niches where saints' shrines had stood were empty now and that the side chapels had been stripped of all their images. Near the top of the church, however, one large canopied tomb remained. A candle burned before it, the only one in that building, which once would have been lit by thousands. A figure stood before the tomb, head bent. We walked towards him, our footsteps ringing on the tiled floor. I caught a faint tang in the air; the incense of centuries.

The figure turned as we drew near. A tall, thin man of about fifty in a white clerical cassock, a tangle of grey hair framing a long, anxious face. The look he gave us was wary and fearful. He leaned back as though wishing he might melt into the shadowed wall.

'Master Kytchyn?' I called.

'Ay. Master Shardlake?' His voice was unexpectedly high. He cast a nervous look at Barak, making me wonder if he had been rough with Kytchyn the day before.

'I'm sorry about the candle, sir,' he said quickly. 'I – it was a moment of weakness, sir, when I saw our old founder's tomb.' He leaned forward quickly and pinched out the flame, wincing as the hot wax burned his fingers.

'No matter,' I said. I glanced at the tomb, where a remarkably lifelike effigy of a friar in Dominican black lay in the dimness, arms folded in prayer.

'Prior Rahere,' Kytchyn mumbled. 'Our founder.'

'Yes. Well, never mind that. I wanted to see the place where a certain Master Gristwood discovered something last year.'

'Yes, sir.' He swallowed, still looking frightened. 'Master Gristwood said to say no word of what we found, on pain of death, and I haven't, I swear. Sir, is it true what this man told me? Master Gristwood has been murdered?'

'It is, Brother.'

'I am not brother,' Kytchyn mumbled. 'I am not a friar any more. No one is.'

'Of course. I am sorry – a slip of the tongue.' I looked around the church. 'Are they to bring the rest of this place down?'

'No.' His face cheered a little. 'The local people have asked to keep what is left as their own church. They are fond of the place. Sir Richard has agreed.'

And their support will be useful to Rich when the prior dies, I thought. I looked around. 'I gather all this began when the Augmentations men found something in the church crypt, last autumn.'

Kytchyn nodded. 'Yes. When the priory surrendered, the Augmentations men came to take an inventory. I was in the library when Master Gristwood came in. He asked if there was any record that might help with something strange they had found down in the crypt.'

'The crypt was used for storage?'

'Yes, sir. It's a big place, there's stuff that's been there hundreds of years. I knew of nothing kept there apart from old lumber, though I'd been librarian twenty years. I swear it, sir.'

'I believe you. Go on, Master Kytchyn.'

'I asked Master Gristwood if he might show me what they had found. They brought me here to the church. It was still whole then, the nave hadn't been taken down.' He looked sadly at the barrier.

'Which part of the church was the crypt in?'

'Over by yonder wall.'

I smiled reassuringly. 'Come, I would have a look. Light your candle again.'

Kytchyn did so with much nervous fumbling, then led us to an iron-studded door. He walked slowly and sedately, the way he would have learned to walk as a young friar. The door creaked mightily as he opened it, the sound echoing through the cavernous church.

He led us down a flight of stone stairs into a long crypt running the length of the church. It was quite dark, with a dank smell. As he led the way, the candle illuminated pieces of lumber and broken statuary. A huge abbot's throne, richly decorated but pitted with woodworm, rose up before us and then I almost cried out as a face loomed out of the gloom. I jumped back, stumbling into Barak, then reddened as I realized it was a statue of the Virgin with an arm broken off. I caught a flash of white teeth as Barak smiled in amusement.