The Prince dismissed his malaise with a brush of his hand. ‘No need. We suspect it results from too much rich food on too many occasions with too many members of the Gascon aristocracy trying to impress with the weight of food on their table.’ He paused as if considering the offer. ‘We are pleased your men accepted a Jew among them; our father granted the Jews safe residence here these twenty years past.’ He allowed a smile of regret. ‘It was to annoy the French more than anything but their payment of eight pounds of pepper every year to the Archbishop is a price worth paying for them to escape persecution.’ He shook his head. ‘Thomas, I am a prince of the realm and it would be unseemly for me to have anyone other than a Christian physician in attendance.’

‘Even privately?’ said Blackstone.

‘Even then,’ said the Prince with a look of regret. ‘Now, what of this other matter you have waited patiently to bring to us?’

Blackstone recounted how he had rescued Beyard and Lázaro and then the boy’s story of what he had witnessed.

‘After they murdered the Queen, the lad escaped to the coast. The captain of the guard who played no part in the killing was a man from a noble family who abhorred what they had done. The boy worked on galleys for three years and then came ashore. He went inland with the supplies destined for Charles of Blois and was caught up in the fighting at Cocherel and captured. From there he was sold to Ranulph de Hayle. I questioned one of de Hayle’s men and he told me they had been in Castile. It seems a stroke of ill fortune for the boy and the opposite for de Hayle but I think the lad was being hunted and had been for the past three years. I believe the boy’s survival confirms King Pedro’s complicity in his wife’s murder.’

‘But why was the boy held captive by de Hayle and not slain?’ said the Prince.

‘Because Ranulph de Hayle was going to sell him to the French.’

Realization dawned on the Prince. ‘Of course! She was King Jean’s niece and the boy’s evidence would give the new King added impetus to his desire to attack Castile in support of Pedro’s half-brother.’

‘And that will draw us into war because of our treaty with Don Pedro,’ said Blackstone. He took a small pouch from his belt and emptied out a beautiful crucifix, too exquisite to belong to a servant. ‘The Queen gave the boy this to protect him moments before they murdered her.’

The Prince fingered the delicate gold filigree. ‘She wore this moments before she died?’

‘Aye, lord. She had only a few breaths left in this life after she gave it to him. Once he had made his escape, he stitched it into the seam of his hose.’