'There are four,' Sir Richard explained, 'one for the front, one for the back and one for each side of the cart. These will be fastened on and above them a platform. On that will be set the tableau. Everything has to be correct,' he commented. 'We do not wish to bring any disgrace or dishonour on the guild from our cart collapsing as it rolls through the streets of Cheapside.'

No expense had been spared. Athelstan particularly examined each of the screens showing the four last things; Death, Judgement, Heaven and Hell. He admired the sheer complexity of the scenes as well as the genius of the craftsmen, in particular in their depiction of Hell. There was a representation of the devil carrying off the wicked to Hades. Each of the damned souls was guarded by a group of hideous demons. In the centre of the piece was a carving of a shoemaker resisting four shaggy devils who were dragging him from the embraces of what at first Athelstan thought was a young lady but, on looking closer, realised that with his tail and close-cropped hair, it was a depiction of a male prostitute. The profession of the Devil's captive, a shoemaker, was made apparent by the bag of tools clutched in one hand and the unfinished shoe in the other.

'Who carved this?' Athelstan asked Sir Richard.

'Andrew Bulkeley.'

'Where is he?'

Sir Richard turned and called the man's name and a small, bald-headed man wandered over. His vast form, more corpulent than that of Cranston, was swathed in a dirty white apron. He looked like one of the carefree devils he had carved, with his fat, cheery face, snub nose and large blue eyes which seemed to dance with wicked merriment.

'Master Bulkeley.' Athelstan smiled and shook the proffered hand. 'Your carvings are exquisite.'

'Thank you, Brother.' The voice betrayed a soft burr of warmer, fresher climes.

Athelstan pointed to the depiction of Hell. 'This particular carving, it's your work?'

'Yes, Brother.'

'And the idea is yours?'

'Oh, no, Brother. Sir Thomas himself laid down what we should do and how we should carve it.'

'But why the shoemaker and why the male prostitute?'

The craftsman wiped his mouth with the back of his hand.

'I don't really know. I have done such scenes many times. It's always the same. Someone being dragged from the warm embraces of a group of young ladies. But this time, I think Sir Thomas had some secret joke. He insisted that it be a shoemaker and the prostitute be male. That's all I know. He paid the money, I did what he asked. Have you seen the others?'

'Yes, thank you,' Athelstan said, and looked across at Cranston.

'Master Allingham came out to look at these carvings?' Cranston asked.

'Yes.'

'Do you know why?'

'No.'

'Any carving in particular?'

The craftsman shrugged.

'He'd look at them all, usually when we were not there, but he constantly asked why Sir Thomas had chosen certain themes. I gave him the same answer I gave you.'

Athelstan turned to the merchant. 'Was your brother fascinated by shoemakers?'

'I told you,' Sir Richard replied, exasperated, 'he liked riddles. Perhaps a shoemaker had offended him. I don't know!'

Athelstan touched Sir John gently on the elbow. 'I have seen enough. Perhaps we should go?'

The coroner looked puzzled but quietly agreed. They walked back through the kitchen and down the hallway to the front entrance of the house. They were about to leave when Sir Richard called out: 'Brother Athelstan! Sir John!'

They both spun round.

'You keep coming back here, yet you have not found any evidence linking the deaths, or the reasons for them. Is that not so?'

The merchant had regained some of his arrogance and Cranston could not stop himself.

'Yes, that's so, Sir Richard. So far we have found nothing conclusive. But, I can tell you something fresh and you may tell the others.'

'Yes, Sir John?'

'Whatever the evidence, whatever you may think, Stephen Allingham was murdered. You should all take care!'

Before the startled merchant could think of a reply, Cranston had taken Athelstan by the elbow and steered him out into the sun-baked street.

'Last time we were here,' Athelstan quipped, 'you warned me, Sir John, not to open my mouth and say things I was not bidden to. Yet you have done so today. There is no evidence that Allingham was murdered.'

'Oh, I know that,' Sir John grunted. 'And so do you.' He stopped and tapped the friar gently on the temple. 'But up there, Athelstan, and here in your heart, what do you really think?'

Athelstan stared at the hubbub around them, the people oblivious to his dark thoughts of murder, fighting their way through the stalls, gossiping, talking, buying and selling, engaged in everyday matters.

'I think you are right, Sir John. Allingham's murder was well planned, and the murderer is in that house.' He pulled his cowl up against the hot midday sun. 'Shall we collect our horses?'

Sir John looked away sheepishly. 'Sir John,' Athelstan repeated, the horses, shall we collect them?'

Cranston let out a sigh, shook his head and gazed appealingly at Athelstan.

'I have bad news, Brother. We are summoned to Westminster. Chief Justice Fortescue believes that we have spent enough public money and time in the pursuit of what he calls will-o'-the-wisps. He wants us to account for our stewardship. But before I clap eyes on his miserable face, I intend to down as many cups of sack as I can! You are with me?'

For the first time ever Athelstan fully agreed with Sir John's desire for refreshment. They walked quickly through Cheapside down to Fleet Street and into the Saracen's Head, a cool, dark place off the main thoroughfare. Athelstan was pleased to see that it was empty and insisted that this time he should be host. He ordered the taverner to bring two black-jacks of brimming ale and, since it was Friday, not meat but a dish of lampreys and fresh white bread for himself and Sir John. Cranston took to the food like a duck to water, smacking his lips, draining the black-jack, and shouting for the taverner's pot boy to come and fill it again. Once the first pangs of hunger had been satisfied, Cranston interrogated the friar.

'Come, Brother, what do you think? Is there a solution? You are the philosopher, Athelstan, though didn't one of your famous theologians say "From nothing comes nothing – Nihil ex nihiloV '

'There must be an answer,' Athelstan said, reclining against the cool stone at his back. 'When I studied Logic, we learnt one central truth. If the problem exists there must be a solution, if there's no solution there's no problem. Consequently, if there is a problem there must be a solution.'

Cranston belched and blinked at Athelstan. 'Where did you learn that?' he taunted.

'Logic will resolve this problem,' Athelstan persisted. 'That and evidence. The problem, Sir John, is that we have no evidence. We can build no premise without it. We are like two men on the edge of a cliff. A chasm separates us from the other side and now we are looking round for the bridge.' Athelstan paused before continuing, 'Our bridge will be evidence, the resolving of Sir Thomas's riddles about the biblical verses and the shoemaker.'

Cranston shook his head. 'We should have talked to Allingham.'

'We did try, Sir John, but he obstinately refused to confide in us though I agree that he knew something. I think he was either going to flee or perhaps blackmail the murderers, without telling us. He made one mistake. He underestimated the sheer malice of his opponents.'

'What makes you say that?'

Athelstan bit his lip, cradling the black-jack in his hands, enjoying its coolness.

'They relish what they are doing. They plot, they devise stratagems, they cause as much confusion as they can. They not only pursue a certain quarry, the mysteries and riddles of Sir Thomas, I think they enjoy the killing. They have insufferable arrogance. Satan has set up camp in their souls. In a word, Sir John, they enjoy what they do as much as you do a goblet of claret or a game of hazard or teasing me. To them murder is now part of their lives, a piece in the fabric of their souls. They will continue to murder for profit, to protect themselves but also because they want to. All the more to see us floundering around in the dark. The more we flounder, the more enjoyment we give them.'