"What news?"

He had sprinted down into the bustling courtyard to the sight of Elyan and three other knights galloping in through the gates at great speed and then throwing themselves from their horses.

Elyan came right up to him, out of breath, but he kept his voice low so as not to spread panic in those around him. "Morgana's army," he stated. "They have crossed the border. The main force is still some distance away, but there are advance troops that are nigh on two leagues march from here. They'll be at the city walls by nightfall."

Arthur had already suspected as much, but his blood still ran cold at the pronouncement. "Secure the guard," he ordered to a knight standing nearby. "Send out troops to bring in as many refugees as can still reach Camelot in time, and get them safe behind the city walls. Any that can not make it must be told to hide themselves in wilds as best they can." He turned and began striding back up the steps towards the main doors, Elyan all but running beside him. "Do you have any idea of numbers?" he asked him.

"Not as many as when the immortal army attacked," Elyan said. Together they passed inside. "I'd say there were not enough to stage a full frontal siege on us here, my lord. They may try and draw us out to a pitch battle, or attack our men when on patrol."

Arthur stopped walking for a moment, putting his hands on his hips and thinking. "Or almost anything where Morgana is concerned." Then he looked at Elyan. "Thank you," he said. "You have done well. Look to our defences. I must assemble the council."

An hour of talking resulted in no further decisions, and as the light faded from the summer sky, Arthur found himself on the battlements gazing out over his threatened kingdom. Still, people streamed in through the main gate in droves, and he could see dozens more on the approach. Soon the decision would have to be made to close the gates and raise the drawbridge, ensuring the safety of those within, and condemning all those without.

He sighed, his hands tightening on the cold stone in front of him. Then he felt a brush of movement at his sleeve, and turned.

"Guinevere!"

"My lord," she said, her eyes wide as she matched his gaze out over the city walls.

"You would be safer inside," he said with concern.

She smiled gently. "I am safer here than anywhere." Her face was lined with tension, he noticed, and something burned within her eyes. Her smile faded. "She's coming, isn't she?"

Arthur kept his eyes on her face. "Yes," he said.

"Why does she hate Camelot so much?" Gwen murmured. "We were friends once. Why is she doing this?"

Arthur took her hands gently in his, keeping his voice quiet, mindful of his men nearby. "I don't know," he said. "And even if there were the best reason in the world, I doubt it could justify her actions when the victims are innocents."

"I feel…" Gwen began, searching for words. "I feel like I failed her," she finished in a rush.

"How on earth did you fail her?" Arthur asked, turning towards her fully. "What did you ever do but serve her faithfully and be there for her through everything that happened?"

She nodded, but it was a reflex, and it was clear his words hadn't gone in.

"Gwen," he went on. "If anyone failed Morgana, it was me. I grew up with her. I've known her my whole life. And I think of all those things that happened between us, all those things that could have been different, if I'd known – if I'd known she was my sister… I wonder if…"

He felt Gwen's hands tighten on his sympathetically, and saw in her eyes the understanding that comes only with time and shared experience.

And then he said in a quiet voice that only she could hear. "Sometimes I wish my father had never outlawed magic."

He eyes widened. "Do you mean that?" she muttered, aghast.

He nodded, trying to read her expression. "Morgana's hatred of my father – of our father – stems from his hatred of magic, of that I'm sure," he said. "And I don't believe that the young girl I grew up with was evil. She was – wronged, Gwen. I can't think of it any other way."

Gwen looked into his eyes earnestly, her own eyes watering at his compassion for someone who at that moment was making war on everything he held dear. She could have looked into those eyes for eternity.

"My lord!" came the shout from behind them, ripping them apart, and instantly, the dull peel of the warning bell began to toll again.

Arthur and Guinevere let go of each other and turned to the battlements in time to see a stream of torches appear from out of the darkness. It was clear to all watching what the sight meant.

"Close the gates!" Arthur yelled, his order being repeated down the wall to the gate tower.

There were screams from below as the last few refugees made a dash for the entrance, and Arthur saw a tear make its way down Gwen's cheek at the plight of the innocents. The lump in his own throat felt the size of a boulder as he watched the panic set in and the guards rushing everyone towards the gate, which was already closing.

He looked up again at the torches coming ever closer, trying to get a feeling for their numbers: hundreds it looked like. And this was just an advance party, they said. They began to file down in front of the citadel, and he felt a stab of anger at their arrogance at placing themselves so clearly in the firing line with no care.

Then, out of the corner of his eye, he caught sight of a familiar blue, and flipped his head around in time to catch a glimpse of Merlin darting behind him. The boy appeared at his right side, finding a space of his own at the battlements and looking over at the approaching army. His face was pale in the darkness.

Arthur tried to swallow down his instinctive reaction (which was to yell at him and then have the guards drag him off in chains), and turned once again to look out over the wall. "I thought I told you to stay away until you were well again," he growled quietly, barely to be heard amongst the bustle of people around them, the clash of weapons, the hiss of burning torches.

"Miraculous recovery," Merlin explained without looking at him. "Is that Morgana?"

Arthur shot him an angry look, but then sighed, feeling defeated in the face of Merlin's continued… Merlinness. "I haven't spotted her yet," he admitted. "But I'd imagine she'll be there somewhere." He turned his back on his servant and looked at Gwen instead. "I would be happier if you were off the battlements," he told her.

She just shook her head. "As much as I like making you happy, Arthur," she said. "I'm not leaving your side, so you'll just have to live with that."

Arthur turned back, shifting in frustration at his inability to make even two of his subjects do remotely what he wanted them to.

Then there was another scuffle behind him, and Gaius appeared from among the crowds. "Arthur," the physician said, sounding out of breath. "Have you seen…?"

Arthur just pointed.

"Merlin!" Gaius sounded mad, and Arthur even felt a stab of sympathy for Merlin as the boy turned sheepishly to his uncle.

"Sorry," he apologised.

"I thought I told you to stay in your room!" Gaius exclaimed.

"Like that was ever going to happen," Merlin muttered, as Gaius moved round to stand beside him and look over the battlements. But then all the argument vanished from Gaius' lips, as he saw what was arrayed before them.

A sort of hush was falling now over the battlements, a hush pregnant with expectation, as the line of soldiers kept coming and coming, the sound of their footsteps loud and harsh.

Merlin turned his head, and caught sight of a small group of people, all cloaked, making their way down the front line.

"There," he said loudly.

"What?" Arthur followed his gaze.

"It's Morgana."

And there she was. Queen now, of a new land, confident in her growing abilities and the certainty of her hatred for that which she was waging war against. Her men were loyal, they respected her, or at least feared her, and whichever it was, she didn't care. Camelot would not bow to her will when she had ruled there, so now she would break it with force, and destroy all those who had made her life unbearable.

She made her way now along the front of her men, head held high in glee at all that she had done. Uther would never have seen this coming. And Arthur? He would see it, fight it and fall. Then this land would be hers too, and they would all bow to their rightful queen.

"Take care, Morgana," the voice was comforting, and wound through her mind like pungent smoke.

She turned and smiled at the child following close behind her, a gangling boy, not reached his growth spurt, still small, and with a look of innocence that had been the downfall of many. She held out her hand to him and placed an arm round his shoulder, pulling him close. "There's nothing to be afraid of," she said to him soothingly.

"I am not afraid," Mordred spoke clearly, and with a confidence that belied his years. "But we must have all our concentration to perform the spell. There are many watching from the battlements."

Morgana cast the city walls a look of pure hatred. "Is my brother among them?"

"Yes."

"And Merlin?"

"He is there also."

Just as well, she thought to herself. That they may witness my moment of triumph.

"Good," she said. "I wouldn't want the to miss the show."

"Mordred is with her," Merlin mumbled to Gaius in as hushed a voice as he could manage and still allow the old man to hear.

"You're sure?" he hissed back.

Merlin nodded, his eyes now having found the boy walking next to Morgana. "I heard him."

"Maybe now we'll find out what this – dark magic is going to involve," Gaius said. "Is Alvarr there too?"

"I'm not sure," Merlin muttered. "There's several more people down there. He could be one of them."

The figures came to a halt almost parallel to where Arthur was standing, surely not a coincidence, and Merlin could see several guards glancing in the prince's direction as if looking for orders. He swallowed uncomfortably as he could feel Arthur's indecision. Did he order his men to fire? This was clearly an envoy after all, for all that their banners were unfurled, and their purpose was yet un-stated.

Then a lone figure came out from the rest and put all indecision in its place. It was Morgana.

"People of Camelot," she shouted, and they could all hear her as clearly as though she had been standing next to them. "For too long you have cowered behind a tyrant king. For too long have you allowed the evil that is Uther Pendragon to fester in this land, bringing evil and misery wherever he goes."

Furious, Arthur could not help himself from yelling back. "You're one to talk, Morgana!"

His voice had nowhere near the reach of his sister's, but its defiant tone brought a ripple of support from along the battlements, as the knights shifted and murmured.

Had they been standing closer, and had the shades of night not surrounded her, they might have seen Morgana smile.

She continued, undeterred. "You may look upon the new banner under which my men march, under which freedom will be brought to these lands." She turned, raising her hand, and two men stepped forward from the line, both unfurling their huge banners, which fluttered in the torchlight above their heads.

Merlin's eyes went wide, and he turned to Gaius.

There on the banner, the symbol of the rowan tree, and above it, aligned in opposite directions, and appearing to dance in the flickering light, three crows.

Morgana walked undeterred back to her men, and made another gesture. The smaller figure standing among them lifted up a bag that he had been carrying, and drew from its depths a crystal ball. He held it up in his hands, and Morgana coming forwards placed her hands upon it. Then another figure who had been standing to the side, came forward, and placed his hands on hers.

Arthur recognised the man instantly as Alvarr, and opened his mouth to comment on the fact angrily, when he was distracted by a small gasp to his right. Turning, he saw that Merlin was shaking slightly, his hands gripping the stone in front. Whatever was happening to him, he appeared to be struggling not to react. Concerned, Arthur was almost moved to ask him what was wrong, when he saw beneath him a terrible green light begin to spread across the army and out onto the patch of grass in front of them; an unnatural light that centred on the now glowing ball in the hands of his sister.

"My god," he heard Gwen exclaim at his back, and around him he could hear further expressions of fear and despair as people reacted in terror to the unknown power being displayed before Camelot's walls. Then he looked back at Merlin, who was still shaking. Was his servant reacting to this magic, whatever it was that Morgana was doing? He presumed that this was the dark sorcery Alvarr had warned him about, and supposed that it would make sense for someone with magic to feel such a thing on a level he could not hope to understand. He found himself genuinely curious as to what it must be like to be connected to these things, what he had heard referred to as the old religion. Was it wonderful, terrible? Did it open your eyes to new words and new possibilities? Or show you horrors in the dark that you would never forget?

Then Gaius put a supporting hand on Merlin's arm, and by the look on his face, Arthur knew in that moment with shining clarity that Gaius understood what was happening. Which meant of course, that he was aware of his nephew's powers.

Of course he was! How couldn't he be? The two of them lived together, and if he remembered rightly, Gaius had been something of a practitioner of magic himself in days gone by.

Oddly, he found that it didn't bother him that much, even though it also meant that someone else he trusted had been lying to him.

What was it with his subjects anyway? And why was it he had to keep finding out about these things at moments of crisis and when there were loads of other things happening that he should really be concentrating on? Couldn't it all have waited until he was a few years into his peaceful reign, with Guinevere happily looking after their small brood of brawling children, and Arthur growing pleasantly plump after two many feasts and too few campaigns. He might be a bit bored by that stage, and just in the mood for the sort of excitement that could have followed a statement like: "Arthur, did I ever tell you I had magic…?" But no…

"Arthur?"

"What?" he snapped, totally not paying attention now to anything going on anywhere near him but the thoughts inside his head. He whipped round.

Guinevere was pointing down over the battlements, and as he turned to look, he saw the great ball of glowing whatever it was, rise slowly up in the air over the heads of Morgana's army, and start to fly inexorably towards them.

He came back to his wits quickly. "Everybody down!" he screamed, causing a mass ducking of heads as the ball whipped towards them. But it didn't stop. Instead, it flew out over the walls of the citadel, and disappeared down in the direction of the courtyard.

There was a moment of confusion as everyone looked around wondering what the hell had just happened. Then there was a low BOOM that seemed to rise up through them from the very earth itself, and the wall trembled, shaking as though in the grips of an earthquake. There were more screams, but as most people were on the ground already, nobody injured themselves, and the walls proved their engineering worth, staying true and whole, with barely a stone dislodged by the shaking.

When it stopped, a strange silence fell, broken by the faint sounds of cries of human despair coming from the direction of the courtyard.

Arthur leapt to his feet. "The refugees!" he shouted. Turning, he caught sight of Sir Leon further along the wall, and the two met eyes. "Go!" he shouted. "See what the situation is!"

As Sir Leon departed swiftly, taking with him a contingent of knights, Arthur turned back to his sister with fury in his heart.

"Morgana!" he yelled. "I do not know what you have done, but know this, Camelot shall not fall while I command her!"

"Ah my dear brother," she called back with scorn. "Do not make promises you can not keep. In four day's time, a great demon shall rise in your midst and lay waste to your mighty kingdom. Camelot and her people shall be no more, and our father will finally have paid for his crimes."

As she turned and began to walk away, Arthur hit out the stones in anger, and turning himself, began to run in the direction of the courtyard, dodging around anyone in his way. He reached it quickly, and stopped in horror at the sight of the gaping black hole in the very centre. Around it lay the burnt bodies of numerous individuals who had clearly not been fast enough to get out of the way as the powerful spell had approached, and a general wailing was going up from friends and relatives clutching their loved ones, and from those who were uninjured and unaffected, but still fearful of what they had just witnessed. Already, he could see his knights organising litters to carry the injured away, moving people back from the hole, and generally taking charge. He felt a moment of pride, even in the darkness.

The rest of the evening faded into a blur in his mind: the sight of Guinevere striving to care for the injured, smiling at them reassuringly while keeping her sorrow tightly controlled; Gaius, his face ashen, struggling between one victim and another, tending, bandaging, bringing relief to the dying.

But there amongst it all, one memory did stand out: the sight of Merlin alone and unmoving, looking fixedly at the hole in the courtyard, with an expression of horror and terror that Arthur hoped to never see on another individual's face for as long as he lived.

TBC