A peal of bells sounded from the direction of the monastery, loud in the still air.

'They've seen us coming,' Mark said with a laugh.

'They'd need good eyes. Unless it's one of their miracles. God's wounds, those bells are loud.'

The tolling continued as we approached the walls, the noise reverberating through my skull. I was tired and my back had pained me increasingly as the day wore on, so that now I rode slumped over Chancery's broad back. I pulled myself upright; I needed to establish a presence at the monastery from the start. Only now did I appreciate the full extent of the place. The walls, faced with flints set in plaster, were twelve feet high. The enclosure reached back from the road to the very edge of the marsh. A little way along there was a large Norman gatehouse, and as we watched a cart laden with barrels and led by two big shire horses rattled out onto the road. We reined in our horses, and it rumbled past us towards the town, the driver touching his cap to us.

'Beer,' I noted.

'Empty barrels?' Mark asked.

'No, full ones. The monastery brewhouse has a monopoly in supplying the town's beer. They can set the price. It's in the founding charter.'

'So if anyone gets drunk, it's on holy beer?'

'It's common enough. The Norman founders kept the monks comfortable in return for prayers for their souls in perpetuity. Everyone was happy, except those who paid for it all. Thank God, those bells have stopped.' I took a deep breath. 'Now, come. Don't say anything, take your lead from me.'

We rode up to the gatehouse, a solid affair faced with carvings of heraldic beasts. The gates were closed. Looking up, I glimpsed a face peering down from the window of the gatekeeper's house on the first floor, quickly withdrawn. I dismounted and banged on a small side gate set in the wall. After a few moments it opened to reveal a tall, burly man with a head as bald as an egg, wearing a greasy leather apron. He glared at us.

'Wod'ya want?'

'I am the king's commissioner. Kindly take us to the abbot.' I spoke coldly.

He looked at us suspiciously. 'We're expecting nobody. This is an enclosed monastery. You got papers?'

I reached into my robe and thrust my papers at him. 'The Monastery of St Donatus the Ascendant of Scarnsea is a Benedictine house. It is not an enclosed order, people may come and go at the abbot's pleasure. Or perhaps we are at the wrong monastery,' I added sarcastically. The churl gave me a sharp look as he glanced at the papers – it was clear he could not read – before handing them back.

'You've made them richer by a couple of smears, fellow. What's your name?'

'Bugge,' he muttered. 'I'll have ye taken to Master Abbot, sirs.' He stood aside and we led the horses through, finding ourselves in a broad space under the pillars supporting the gatehouse.

'Please wait.'

I nodded, and he stomped off and left us.

I passed under the pillars and looked into the courtyard. Ahead stood the great monastery church, solidly built of white stone now yellow with age. Like all the other buildings it was of French limestone, built in the Norman way with wide windows, quite unlike the contemporary style of high narrow windows and arches reaching to the heavens. Big as it was, three hundred feet long and with twin towers a hundred feet high, the church gave an impression of squat power, rooted to the earth.

To the left, against the far wall, stood the usual outbuildings – stables, mason's workshop, brewery. The courtyard was full of the sort of activity familiar to me from Lichfield: tradesmen and servants bustling to and fro and talking business with monks in the shaved heads and black habits of the Benedictines; habits of fine wool, I noticed, with good leather shoes showing underneath. The ground was packed earth, littered with straw. Big lurcher dogs ran everywhere barking and pissing against the walls. As with all those places, the atmosphere of the outer court was of a business rather than an enclosed refuge from the world.

To the right of the church the inner wall separated off the claustral buildings, where the monks lived and prayed. Against the far wall stood a separate, one-storey building with a fine herb garden before it, plants staked out and carefully labelled. That, I guessed, would be the infirmary.

'Well, Mark,' I asked quietly, 'what do you think of a monastic house?'

He kicked out at one of the big dogs, which had approached us with raised hackles. It backed off a little, to stand barking angrily. 'I had not expected anything so large. It looks as if it could support two hundred men in a siege.'

'Well done. It was built to provide for a hundred monks and a hundred servants. Now everything – buildings, lands, local monopolies – supports just thirty monks and sixty servants, according to the Comperta, on the fat of the land.'

'They've noticed us, sir,' he murmured, and indeed the cur's continued barking had drawn eyes from all over the courtyard – unwelcoming eyes, quickly averted as people whispered to each other. A tall, thin monk, leaning on a crutch by the church wall, was staring fixedly at us. His white habit with its long scapular in front contrasted with the plain black of the Benedictines.

'A Carthusian, unless I'm mistaken,' I said.

'I thought the Carthusian houses were all closed, with half the monks executed for treason.'

'They were. What's he doing here?'

There was a cough at my elbow. The gatekeeper had returned with a stocky monk of around forty. The fringe round his tonsure was brown streaked with grey and he had a hard, strong-featured, ruddy face, whose lines were softened with the sags and pouches of good living. A badge of office showing a key was sewn onto the breast of his habit. Behind him stood a nervous-looking red-haired boy in a novice's grey robe.

'All right, Bugge,' the newcomer said in the harsh clear accent of the Scots, 'back to your duties.' The gatekeeper reluctantly turned away.

'I am the prior, Brother Mortimus of Kelso.'

'Where is the abbot?'

'I fear he is out just now. I am his second in command, responsible for the daily administration of St Donatus.' He gave us a keen stare. 'You have come in response to Dr Goodhaps's message? We have had no messenger to tell us you were coming, I fear there are no rooms ready.' I took a step back, for a ripe odour came from him. I knew from my own education by the monks how rigidly they clung to the old notion that washing was unhealthy, bathing only half a dozen times a year.

'Lord Cromwell sent us at once. I am Master Matthew Shardlake, appointed commissioner to investigate the events reported in Dr Goodhaps's letter.'

He bowed. 'I welcome ye to St Donatus Monastery. I apologize for our gatekeeper's manners, but the injunctions require us to keep as separate as possible from the world.'

'Our business is urgent, sir,' I said sharply. 'Kindly tell us, is Robin Singleton truly dead?'

The prior's face set and he crossed himself. 'He is. Struck down most foully by an unknown assailant. A terrible thing.'

'Then we must see the abbot at once.'

'I will take ye to his house. He should be back shortly. I pray ye may cast light on what has happened here. Bloodshed on consecrated ground, and worse.' He shook his head and then, with a complete change of manner, turned and snapped at the boy, who was staring at us with wide eyes. 'Whelplay, the horses! Stable them!'

He seemed scarcely more than a child, thin and frail-looking, looking more like sixteen than the eighteen necessary to qualify for the novitiate. I removed the pannier containing my papers, handing it to Mark, and the boy led the animals away. After a few paces he turned and looked back at us, and in so doing he slipped in a mess of dog turds and went over backwards, landing on the earth with a crash. The horses stirred anxiously and there was a ripple of laughter round the courtyard. Prior Mortimus's face reddened with anger. He crossed to the boy, who was pulling himself to his feet, and pushed him over to land again in the dog mess, bringing more laughter.