And when they returned it was with grievous tidings: for though they had rescued the Queen after a long and hard journey, they had lost one of their number – the Queen's beloved brother, Sir Elyan, and one of the finest among the knights.

I did not know Elyan well. I had spoken with him once or twice – he had been polite, but with a good sense of humour; he had been an excellent friend to the other knights – Gwaine and Percival did not attempt to hide their tears, for they had laughed and joked together, and now at Morgana's hand their friend had been cruelly ripped from them.

Yet there could be none more affected, surely, than the Queen herself – dear Guinevere, tortured, it transpired, by Morgana, driven to the edge of insanity, as I had been – and now bereft of a brother she had loved. Camelot gave Elyan a grand send-off, which I attended with Gaius and Merlin; the King and Queen were at the fore of the sombre ceremony. I tried not to stare at the Queen, but I could not help it, feeling a lurch when I realised that Elyan had been to her as Merlin was to me – or would be if we got on. If I were to lose Merlin... But was he truly the Merlin I had befriended in Ismir?

'I didn't know him,' murmured Mordred sadly in my ear, as we drifted away from the lake, Elyan's final resting-place. 'But he was nice, really nice...'

'I know,' I replied softly. Mordred blamed himself a little for the man's death – the guilt that now struck all of the knights, the guilt that they had let Elyan go before them and so face the trap that Morgana had set first and unaided.

Mordred whispered some other sentiment then, but I did not hear it, because at that moment the Queen walked past us, and on her face was an entirely unexpected expression. She was not with the King or any of her friends among the others; she walked quickly, with a swinging glance; her eyes betrayed something that wasn't sadness, and her mouth was twisted in something that was almost a smile.

I must have been staring at her because Mordred asked me what was wrong, and I said, 'Nothing.'

'It's Gwen's face, isn't it? She looks...' Mordred could not find the words.

'Guilty?' I suggested.

'Perhaps...' Mordred said. 'Perhaps she blames herself, or she cannot accept it, or... It is a terrible thing that has happened to her; it is a tragic thing to lose a brother...'

'I know,' I replied definitely.

So Morgana was back, and definitively established in the edifice known only as the Dark Tower: a forbidding structure in which the knights had found Gwen in that state of almost-madness. Perhaps it was her madness that made her act strangely. Whatever it was, it was too much to suffer, and all of Camelot pitied the reduction of the proud and kind queen to a shadow of her former self.

Morgana was back, and that rather than the Queen's condition was what occupied the court and Camelot. The King did not mean for the information to leave the court, but gossip spreads quickly in Camelot, and soon everyone knew anyway. But they did not panic, merely awaited the King to make his next move, because they trusted him, for he was shrewd and always did what was best for Camelot.

The King was onto the matter. But that did not change the very fact that Morgana was back.

Mordred did not seem affected for a good few days, occupied as he was with matters of the Round Table. But one evening when I went to see him in his quarters I found him sitting on his bed with his head on his hands, and he was shivering. He did not notice my entrance until I was right beside him.

'What is it?' I asked.

'Morgana. Morgana's back.'

His voice was that of a man haunted, one who could not escape from a hoard of bad memories. 'She's back, and I can feel it. Like I'm still tied to her – God, Ganieda, it's so cold, can't you feel it?'

I put my hand on his, and found it to be warm and clammy. I wondered if he had a fever. 'You should go to Gaius. You don't look well at all.'

'It's dark magic, not some stupid sickness,' he retorted in an unusually harsh voice. Then he apologised for snapping at me. 'I'm sorry, Ganieda; please, you should go. I'm not myself this evening, you can see that.'

'Are you sure you don't need me?'

I looked straight into his eyes then, those innocent eyes, the eyes of a child who has seen too much; and he clutched at my arm, and then locked me in a tight embrace. 'I have never needed anyone like I need you. But for your sake – Oh, God, no, don't go, forget I ever told you to go. Stay here. Stay right here...'

His babbled statements ended in a choked sob, and I put my arms around him, holding him until the terrible shivering stopped, holding him long into the heavy dusk that descended over Camelot that evening.

'So Mordred hasn't joined Morgana,' said Merlin in a scornfully light-hearted manner, later when I had returned home.

'Merlin, he would never join Morgana. He's too afraid of her, anyway. Have you not seen him? – the very knowledge that she is back has made him ill.'

'And so it should do.'

'What? What do you mean?'

'He was stupid enough to join her in the first place.' Merlin reached over and grabbed a book from the desk in our room. 'If this illness is what's stopping him from going back – let him be ill. I don't care. It's better that way.'

'Merlin, oh, Merlin! Merlin, how could you say that?'

He did not reply, pretending to be absorbed by the book. I ignored that it was getting late, and stormed from the quarters.

I leaned out of the slim window, feeling the fresh night air on my nose, cooled by the light breeze that dispersed the humidity that had hung in the air all day. The view over Camelot was as spellbinding as ever: the motley jumble of coloured roofs, the now-empty market-place with the tall statues casting long and eerie shadows, the sprawling wings of the grand castle and the city walls. I never failed to be calmed by such a view, and chose that particular window – one that opened off a communal corridor near to the King's quarters – as my vantage-point when I wanted to escape from my arguments with Merlin.

I do not know how long I sat there on that particular night, but I must have drifted off for a bit, because when I opened my eyes I found the clouds outside to have cleared and revealed the constellations to have moved a little across the sky.

I rubbed my eyes, wondering why Gaius hadn't come to find me; I was about to return to the quarters when I heard footsteps.

I was still unsure about the rules on curfew in Camelot. I knew that it was an offence to be caught in the streets after the bell had rung – especially now, when the town was on high alert – but I believed that it was also unfavourable to be found wandering the corridors late at night. Fearing the steps to belong to a guard I huddled into the alcove with the window in it, sitting tight in the shadows and holding my breath.

The steps came closer, and then they reached my alcove. I saw a figure approach – a figure in a dark cloak drawn low over the face and swirled tightly around the body. A breeze from the window tugged a little at the hood; I caught a glimpse of a face I thought I knew, but which was too shadowed for me to identify, and anyway I was tired and not especially alert, concentrating all my energies on remaining unseen. But I knew it wasn't a guard.

The suspicious figure did not see me; and as it passed I jumped up silently and followed at a safe distance; but a few turns of the corridor later I had lost sight of it. I wondered whether to report my sighting; I tried to find a guard nearby, but there were none, and I was falling asleep on the spot; in the end I went to bed, resolving to say something in the morning, but morning arrived and my brain had cleared all recollection of the incident.

It was midday before I remembered what I had seen, and only then because I saw the Queen walking down one of the darker corridors in the castle; and as irregular shadows fell across her face I realised who it was I had seen and recognised during the night. A sigh of relief escaped me; if the Queen wanted to undertake night-time excursions, nothing should stop her. She was the Queen after all. I did not need to feel bad about not reporting the incident.

I hindsight, though, I really rather wish I had...