‘Richer was working on copying the “Liber”,’ Athelstan murmured once the monks had left. ‘And when he finished, he placed that and the original in a pannier, returned to hastily hide them in his chamber, then left to meet whom?’

Cranston just pulled a face. Master Crispin was called next. The secretarius was sullen, openly resentful at being kept in the abbey. Once he’d taken the oath on the Book of the Gospels he admitted he was shocked at the horrid deaths.

‘And where did you spend your sleeping hours?’

‘In my bed, Sir John. I wish to be free of this place. I never liked it. I know nothing of these deaths.’

‘Murders,’ Athelstan broke. ‘Murders, Master Crispin, heinous slayings for which someone will undoubtedly hang. You’re on oath — do you have anything else you can tell us?’

‘No.’

‘Then, sir, go back to your chamber and wait.’

Prior Alexander came next. He looked woebegone and exhausted, face unshaven, eyes red-rimmed with weeping. He mumbled the oath and slouched like a broken man on the stool.

‘He’s gone.’ The prior lifted his head. ‘Beautiful Richer.’ He heaved a deep sigh. ‘My friend, oh. .’ Prior Alexander seemed unaware of his surroundings or to whom he was talking. ‘He was a butterfly in many ways. I knew his only task here was to secure the return of everything plundered from St Calliste, including that bloodstone. God knows,’ Prior Alexander screwed his face up, ‘the curse that ruby carries, now he and one of the Wyvern are dead, murdered.’

‘By whom?’

‘God knows, Sir John. I would suspect the Wyverns but one of them died with him, perhaps they fought. .’

‘Richer hated them, yes?’

‘Of course.’

‘Enough to meet one of them at the dead of night and attempt to kill him? After all, Richer was armed with a dagger?’

‘Why there?’ Prior Alexander pleaded. ‘Why in the hog pen?’

‘Why indeed,’ Athelstan answered. ‘Prior Alexander, you loved Richer.’ Athelstan put his pen down. ‘I do not wish to know to what extent or in what way but he came here to reclaim plundered property. Richer arrived at St Fulcher’s once his uncle at St Calliste knew the Wyverns were here. He turned the minds of Master Chalk and Sir Robert to the truth about the Passio Christi?’

‘Yes.’

‘He persuaded Sir Robert to bribe your Lord Abbot for the secret return of those items.’

‘Of course. You know our Lord Walter, he and Judas would have been true blood brothers.’

‘You hate your abbot?’ Athelstan insisted. ‘You regard him as venal, pampered and corrupt.’

Prior Alexander did not answer.

‘He made it clear that Richer would soon leave, after all, there was little else for him to take back to France except the “Liber”. Is that why you killed the abbot’s pet swan Leda and hanged it on the abbey gallows? You wrote that threatening message which is nothing more than a translation of a quotation inscribed along the edge of an altar in one of your chantry chapels. You made it appear that the threat came from the Upright Men because you sympathize with them, hence your anger against Lord Walter for stopping payments to them.’

‘The swan — true I strung the bird from the gallows,’ Prior Alexander shook his head, ‘but I never killed it. Richer found it dead in the abbot’s garden. The swan died, Brother Athelstan, like all his pets do, from overeating. You saw how he constantly fed it morsels from his table, sweetmeats, sops of wine, cream, and fragments of marzipan. The arrogant fool was more concerned at appearing to be the swan’s lord and master than the man who should protect it. For God’s sake,’ the prior scoffed, ‘do you think I would kill some hapless bird out of spite? Don’t you know anything about Mother Nature? Swans are not to be fed such a surfeit of richness. I hanged the corpse as revenge but I did not kill it.’

Athelstan sensed the prior was telling the truth.

‘Do you know what passed between Richer and Sir Robert?’ he asked. ‘What really turned the minds of a ruthless city merchant, not to mention a professional killer like Chalk, to repentance and reparation?’

‘I know nothing about Richer’s conversations with Master Chalk or Master Crispin.’

‘He talked with the latter?’

‘Of course, when Sir Robert sent him here.’

‘Did you treat Crispin for his eye sight?’

‘Yes, I used to be the infirmarian here. I’m skilled in dealing with infections of the eyes but there was little I could do. Years of straining over memoranda books had taken their toll.’

‘Do you think Richer killed the Wyverns?’ Cranston asked.

‘I heard you found Osborne’s corpse, or at least the Fisher of Men did,’ Prior Alexander murmured. ‘It’s possible,’ he confessed bleakly. ‘Richer did hate them. He was young, vigorous and, by his own admission, skilled in arms. He performed military service before he entered the novitiate.’ Prior Alexander became more composed.

‘And you know nothing about the murders amongst the Wyverns?’

‘Nothing. My only concern was that Richer stayed. Sir Robert paid the monies. The abbot released the items plundered from St Calliste. I allowed Richer to go into the city to arrange those meetings with envoys from foreign ships. Does it really matter if precious objects were returned to their rightful owner? Abbot Walter was happy and Richer was content, whilst I was only too pleased to help.’

‘The “Liber Passionis Christi”, which we now have — you should have told us the truth.’

Prior Alexander just glanced away.

‘Well?’

‘Abbot Walter, and on this I agreed with him, declared that we must have a copy so that if a royal inquisition ever took place on the goods from St Calliste, we could produce like for like, at least show we had a copy of that valuable manuscript. Richer seemed very pleased with that. He personally supervised the copying both in the scriptorium and his own chamber.’

‘Tell me.’ Athelstan paused. This mystery was gathering like a boil about to bust its venom. ‘In your own mind Prior Alexander, and this is very important, did Sir Robert secretly plan to bring the Passio Christi not to St Fulcher’s but across to France and personally return the bloodstone to St Calliste?’

‘No.’ Prior Alexander shook his head vigorously. ‘I truly do not know what passed between Richer and Sir Robert except Kilverby, that cunning merchant, had a change of heart. He certainly told me, on the very afternoon before he died, when Richer and I visited him, how he would leave the bloodstone at St Fulcher’s and that would settle his conscience. He’d give it back to the Benedictine order. However, which monastery or abbey housed it was not his concern.’

‘Richer would have left now that the “Liber” was copied?’

‘Yes.’

‘And you resented that. I know you argued hotly about it.’

‘Of course we did! Why, Brother Athelstan, are you saying I killed my beloved friend?’

‘Lovers argue; they can even kill.’

‘We were not lovers in that sense,’ Prior Alexander whispered, eyes all fierce.

Athelstan held his gaze. ‘So how did you, Prior Alexander, spend yesterday evening and the early hours of this morning?’

‘I attended divine office. Well, I had to; for the rest I stayed in my chamber.’

‘Waiting for Richer?’

‘Yes, Brother Athelstan, waiting for Richer. He told me he intended to work late. I waited and waited,’ Prior Alexander’s voice broke, ‘but he never came.’

Athelstan looked at Sir John, who’d sat with his eyes half closed throughout this interrogation.

‘We need keep Prior Alexander no longer,’ Athelstan murmured. ‘He can leave and bring Wenlock before us.’

Wenlock was helped to his seat by one of the lay brothers; the old soldier looked pale, simply dressed in his nightgown, a cloak around his shoulders. He clutched a bowl explaining that he still felt nauseous and had been vomiting since yesterday evening.