'Stop, Morgian. Your wiles cannot avail you now.' He turned to the High King and said, 'The hurt this woman has done me, I readily forgive. It is for the harm that she has caused others that she is to be judged.'

'You are not my judge,' hissed the woman.

'The High King of Heaven is your judge,' the Emrys replied. 'And the Pendragon of Britain serves as the steward of his justice in this worlds-realm.'

'Well spoken,' said Arthur. 'Let us hear the accusations against her.'

The Emrys turned once more to Morgian and raised his arm, forefinger extended. 'I charge you with the countless treasons great and small, practised against humanity and against Britain. I charge you with sedition, perfidy, wickedness and blasphemy. I charge you with evil most loathsome and foul. I charge you with the murder of Pelleas, my friend and loyal servant of King Arthur. I charge you with the death of Taliesin, my father.'

The Pendragon heard this gravely. 'What do you say to these charges?'

The Queen of Air and Darkness tilted back her head and laughed. A more ghastly sound I hope never to hear. 'Do you think I care about these trifles?'

'Murder is no trifle, woman,' Arthur said.

'No? How many men have you killed, Great King? How many have you slain without cause? How many did you cut down that you might have spared? How many died because you in your battle-rage would not heed their pleas for mercy?'

The High King opened his mouth to speak, but could make no answer.

'Do not listen to her, Bear!' cried Bedwyr. 'It is a trick!'

'Speak to me of trickery, Bedwyr the Brave!' Morgian whirled on him. 'You who have lain in ambush for unsuspecting prey, who have attacked and killed by stealth! How was it in Celyddon when you sneaked through the wood? Did not your heart beat fast with the thrill of your deception? Did it not leap for joy to see the fire spread at your enemies' backs? You are a master of trickery, it seems to me.'

Bedwyr glared at her and turned his face away. Cai rushed to his defence. 'It was war! We did only what we had to do.'

Like a cat with claws unsheathed, Morgian leapt on him. 'War! Does that absolve your guilt? You murdered men whose only crime was wanting to feed their children and see them grown. You made orphans of those same children and gave them up to the slow agony of starvation. You made widows of wives who knew nothing of realms or rulers. You stole the breath from their lungs and light from their eyes for ever. But how would you know – you, who have never shared bed with a wife?'

Cai, red-faced, was shamed into silence. But Morgian was far from finished. 'Nothing more to say, bold Cai? Come, speak to me again of the cruel necessity of war.'

'Hold your tongue,' warned Gwalcmai ominously.

'Are you displeased, my son?' Morgian turned on him. 'You and your brother should be the last men alive to seek my death. We are blood kin, are we not? What would your father say if he learned his sons had caused his mother's death?'

'You are no blood kin of ours!' spat Gwalchavad.

'Ask Lot of Orcady about that,' she answered sweetly in reply. 'Or have you never wondered how he came by twin sons when his own wife was barren?'

It was an awesome display. She knew precisely the words to say to cow each and every one of them. I began to wonder if any man alive could stand against her. Surely, she was the Queen of Air and Darkness!

Gwenhwyvar stepped fearlessly forward, chin thrust out. 'You are shrewd, woman,' she said. 'I give you that. But sons are not responsible for their father's actions.'

'Oh, yes,' replied Morgian archly, 'speak to me of fathers and their sons. The Barren Queen – is that not what the people call you? Obviously, you know so much – you whose womb is sealed like a gravemound. And why is that? Could it be that you fear the ancient prophecy of your people, that your husband will be killed by his son?'

Gwenhwyvar was astounded. 'How do you know that!'

'I speak with the druids of Ierne, where it is a matter well known – and well known also what you do to prevent this prophecy from its fulfilment.'

Arthur glanced at his wife in shock. 'She is lying!' cried Gwenhwyvar. 'Arthur, my soul, believe me! It is a lie!'

'All our sins,' said the Emrys slowly, 'will be answerable before God. Yours are answerable to the High King now.'

'How can you even think to condemn me when you all have practised crimes far in excess of mine? Where is this justice you are so proud of? Answer me!'

Morgian raised her arm and flung the accusations back at us. I cringed before her wrath. 'You condemn yourselves! Your words are meaningless. Your accusations are the bleatings of dying sheep. Contemptible race, you fly headlong to your own destruction!'

She advanced towards Arthur. Her gloating smile sickened me. 'Did you think to better me? Your justice stinks of piss and vomit! You sicken me,' Morgian screamed. 'Fool!' she shrieked, drew herself up and spat full in the High King's face.

'No!' Gwalcmai leapt forward. He seized Morgian by the arms and spun her round. She spat at him, too, and, with a hiss like a devil cat, raked her fingernails across his eyes. He cried out and fell back, but she leapt on him, kicking and scratching. A long knife appeared in her hand and I watched in horror as she slashed it but a hair's breadth from his throat.

But Gwalcmai was quicker than she knew. Even as he rolled to the ground his hand found his sword, drew it, and raised it as she fell on him. The blade pierced Morgian in the side below the ribs, thrusting up into her black heart.

She shrieked once, stiffened, and stood upright, clutching the sword. The knife fell from her hand and clattered loud on the stones. Morgian stumbled backwards and collapsed upon the ground at Arthur's feet. Blood gushed from the wound and darkened the earth beneath her. Her eyes rolled up into her skull and her limbs convulsed.

It had all taken place so quickly that we stood looking on, stunned and confused, as if caught in a spell of enchantment. The Emrys moved first, kneeling over the still-trembling body.

Gwalcmai stood blinking in disbelief at what he had done. He got to his knees and raised his hands to Arthur. 'Mercy, lord! Forgive me, my king, I could not see her disgrace you!'

Arthur stared at him, and at first I thought he might reproach Gwalcmai. But the Emrys stood and said, 'Morgian is dead. In her bloodlust she has fallen on the sword Gwalcmai raised for his own defence. I see no fault here.'

Arthur turned to Gwalcmai who still knelt before him. 'Rise, Gwalcmai, you are forgiven. No doubt God has called her to answer her crimes as we will answer for our own.'

I heard a strangled sound and turned. Medraut stared at the body on the ground, his face contorted in a strange and unnatural expression: dark eyes wide with fear, lips curled in a ghastly leer of hatred, pale skin dark with rage. His fingers were curled like claws and he was scratching at his face in long raking welts. Ruby blood-drops oozed from the wounds and rolled down his cheeks.

Bedwyr was nearest and put out a hand to stay him. Medraut dodged aside. 'Stay back!' he cried in a shattered voice. 'Do not touch me!'

We looked in wonder at one another.

'Peace, Medraut. It is finished,' the Pendragon soothed.

'Murderer!' Medraut screamed, backing away. 'Murderer!'

Cai stepped close and made to grab him. Medraut's hand whipped up. The glint of a knife sparked in the fading light and Cai's arm spouted blood. He let out a cry, more in surprise than pain, and jumped back.

Medraut turned and fled to the horses. Llenlleawg unsheathed his sword and ran after him. Medraut slashed the reins free from the picket line with his knife and leapt into the saddle in one motion. He wheeled the horse and galloped away before the Irishman could reach him.