Arthur wasn't too sure about it, in fact was massively sceptical about the whole mess. Gaius claimed that it was the bond between him and Merlin that caused the problem and that the bond had to either be severed or strengthened enough to pull Merlin out of the space between worlds.

It sounded easy enough. Gather wood, drink a potion, chant a few unintelligible words, and then step into the ring of fire, luring Merlin into completing what he'd begun in Camelot, replicating what had started it all since apparently magic demanded balance - whatever that meant, and hope Merlin would think Arthur in danger, push through the trap Merlin had set himself, and 'rescue' Arthur.

They'd done it before with the troll and that awful potion and Merlin had come through, although Arthur learned afterwards that it had been a near thing.

But it was one thing to drink something that merely tasted awful and caused a bit of unconsciousness/near-death on Arthur's part and quite another to deliberately climb into an inferno that could hurt and hurt badly if things went sour.

Gaius was adamant, though. If something wasn't done to test the bond and tighten it enough to pull Merlin back, he might be caught there forever. Something that was theoretically dangerous to Arthur because Merlin always, always, threw himself in harm's way to protect him, no matter the cost. And it couldn't be air or water or earth because the bond had been forged in fire, and in fire, it had to be completed.

It didn't help that Arthur would have to learn a spell. It was one thing to accept that Merlin had magic, had practiced it for years, but Arthur was Crown Prince of Camelot and upholder of the laws governing it. To deliberately participate in something so forbidden as magic damned him in the eyes of his father and his people.

It also didn't make sense. Arthur had no magical powers, but Gaius mumbled something about being born of it would do just as well – which also didn't make sense, but after everything that had happened, he didn't argue. He had quite enough to think about with lying to his father about where he was going, losing his knights while they were 'hunting', and then meeting up with Gaius later for the final preparations.

Surprisingly, it all went off without a hitch. It could have been that Merlin had stopped yammering in Arthur's ear and he could finally think for once. Or it could have been their luck changing. Either way, before he knew it, Gaius and Arthur were standing in front of a cave entrance and planning their next move.

"Sire, this must remain between us. This place is sacred to the Druids and to those with magical abilities. To desecrate it would be an unimaginable loss to both Camelot and Albion." Gaius was looking a bit worried, glancing around as if he expected Uther to come along and hack into the cave with swords and battering rams.

"The Valley of the Fallen Kings is well-known as a haunted place and few would venture inside. Even my father's troops would balk at such a command. Besides, your path was convoluted enough for even the best tracker to lose their way." He meant to imply that he was, of course, perfectly aware of where they were, but truth be told, he had no idea. But when Gaius raised one eyebrow, obviously seeing right through the ruse, Arthur added, "No need to worry, Gaius, I would be able to find my way home easily enough."

"Of course, my lord." Gaius reached down and began to drag one of the branches scattered around the entrance into the cave. "I will need more, enough for a pyre. While I prepare the herbs, perhaps you could gather the rest?"

Arthur nodded, then walked away, looking for dryish logs or anything that might burn easily, although not too dry. It would, after all, be his death if things went awry.

But later, when he began to drag the wood into the cave, he had to stop a moment. He'd never seen anything so beautiful before.

The cave was filled with crystals. Shining in the torchlight, a million prisms were dancing colour across the walls and ceiling, silver and golds and red, blues and greens. As he walked into the chamber, it was almost as if he were inside a crystal globe, dazzling and infinite, breathtakingly intense. As he looked closer, he could see scenes within the crystals, little miniatures of his past life, his favourite horse, the tumble of puppies he'd played with before his father found out and had them destroyed, the glitter and pageantry of the court. Laughing with Merlin at some joke he'd told, the feathered hat he had made just for Merlin, riding with his knights.

He leaned in, dropping whatever he'd had in his hands, trying to look closer. But he was jerked back, Gaius's hand on his shoulder, looking worried. "What did you see?"

Arthur wanted to dive back into the light, see what else he'd find in the stones, but with Gaius frowned, waiting, Arthur shrugged. "I… just things I'd forgotten. In the crystals. Memories of happier times."

"That is not possible. Only those with magic could see into them. Unless…."Gaius said, slowly, carefully, "Your bond with Merlin is a powerful one."

That didn't sound good. It was one thing to help Merlin return, traitorous though it was, but quite another for the Crown Prince to have magical abilities. "I don't like what you are implying, Gaius. I don't have magic."

Gaius nodded. "No, you do not. But nothing like this has ever happened before. Merlin has never happened before. It could be that his magic, loosened by the gateway, is growing wilder, sharing power with you in an attempt to strengthen your connection."

To Arthur, that didn't sound much better than having magic, but Gaius didn't seem to understand his concerns. Instead, pointing to the pile of wood by the entryway, he began to walk past Arthur, and as he did, Gaius said, "In any case, we should hurry. The moon will rise soon and that is when the barriers between the worlds thin out."

But, as far as Arthur was concerned, the wood could wait. He had to know if he'd be cursed with sorcery and everything that implied. "Does this mean I will have magic when Merlin returns?"

He tried to keep the horror out of his voice, but some of it must have bled through. Gaius stopped, then turning back, watching Arthur with confusion, he must have realised how worried Arthur was. Gaius sighed, patting Arthur's arm a moment in reassurance before gesturing toward first one cluster of crystals and then another.

"Arthur, we are standing at the epicentre of all magic. The power of this place will affect everyone who enters here. That's why I chose it, to make it easier to pull Merlin back into this world. But beyond these walls, beyond the entrance to the Valley of the Fallen Kings, no, not likely."

Nodding again toward the pile of logs, Gaius said, "Please bring in the rest of the wood. I've finished the potion. All we need now is the fire-ring to be set and your words and actions upon it. Did you memorize the spell?"

"Of course." Arthur would have been insulted but he had other things on his mind.

Gaius didn't seem to believe him. "Arthur?"

Arthur rolled his eyes, and gave a long, put-upon sigh. "Yes, Gaius, although why can't you say the words?"

"Merlin must be able to hear them and answer." Gaius looked almost sad, as if he'd wanted to be the one plagued with Merlin's mutterings, strange as that seemed. "Much as I've tried, I've not seen nor spoken to him since he… died. Only you." Then he shook himself free of whatever melancholy was troubling him and said, "Now hurry."

The ring of wood was set, herbs thrust into the bark, and Gaius was shoving another potion into Arthur's hands, for protection Gaius said although his magic wasn't strong enough for much – which wasn't reassuring. Suddenly it seemed all too real.

Arthur was no coward, but frankly he was terrified of fire. Too many times he'd watched as people screamed out their pain, shrieks so horrible that they haunted his nights for months afterwards, and there was the scent of burning meat, and the way their hair caught fire and their skin crisped before his eyes.

Gaius must have understood his reticence. He didn't push Arthur, just stood there, waiting to see what he would do. Arthur knew that Gaius would never blame him if he backed out but Arthur wasn't about to back out, not now.

It should be safe enough. The fire once set would surround Arthur but not touch him. To Merlin, it might appear that Arthur was trapped, in danger, and he'd have to go through the flames to rescue Arthur. A completion of what Merlin had begun. If things went well, they'd both be fine, and Merlin back where he belonged. If not, well, Arthur didn't want to think about that.

Off in the darkness in one of the side-tunnels, Arthur could hear Merlin sniffling. I'm sorry, he whispered into the ether, I'm so sorry. And a little later, in a voice half-broken with the sounds of grief, Merlin said, Don't do it, Arthur. I couldn't bear it if anything happened to you. You are worth a thousand of me and I'm just an idiot servant. I should never have started talking to you. I just made things worse and you should go back to being your old prat self and I….

"Shut up, Merlin." It felt good to say it, even if he couldn't see Merlin's face. It was a reminder of what he'd lost and what he would gain once he breathed in enough courage to start.

I don't want to lose you, Merlin said, so softly that Arthur almost didn't hear him. I couldn't bear it.

Arthur nodded. "I have stocks waiting for you, idiot, and a pile of vegetables with your name on it. I've been practicing my aim just in case the peasants miss."

I can't wait.

"Neither can I." And with that, Arthur grabbed the vial in Gaius's hands, downed it in one gulp, then stepped into the centre of the wood ring.

As Gaius shoved the torch into the logs and the herbs caught fire, Arthur began to chant. " Geondbæl, geat onscíeteþ. Merlin, onierne sé geat ond edhwierfe."

Merlin's voice was filled with horror. Don't be such a prat. Get out of there before….

One of the logs spat out pitch, a sharp sound, and Merlin gave a frantic cry. No! Don't do this. I don't know how to get back. I don't. You'll die and it will be my fault. Please, Arthur, no!

The flames were already leaping up, but Arthur tried to ignore them, tried to breathe in cool air enough to say, "Merlin, onierne sé geat ond edhwierfe."

Merlin was shouting, and mixed in with his cries, Arthur thought he heard humming, a low vibration rising sharp into worry. He couldn't see anything beyond the flames, but above him, the crystals were glowing with reds and blacks, reflections of the fire intense in a thousand sharp facets of stone. As he watched, the light seemed to merge impossibly bright, then exploded, lighting up the cave in an inferno.

Fire rained down on him. He reached up, trying to shield his face as flames crackled above his head. Then the blaze spread, falling to his feet, racing across the stone where no wood burned. Still, batting at the cluster of heat and pain around his head, trying to stamp out the flames at his feet, he couldn't see through the fire, could hardly speak. His lungs were seizing up, and it felt as if he were ablaze, too.

Agony increasing with every movement, clothes starting to smoulder, and a great blast of flames reached up, biting into his skin, and the side of his face, and a jolt up his arm. Arthur drew in a sharp breath, trying not to whimper.

Merlin was crying now, screaming for him to get away. No, no, Arthur, don't do this. No, please, no.

"Merlin, onierne… sé geat… ond edhwierfe… Merlin, I'm… sorry."

Before his eyes, another burst of light reddened everything, the heat pushing down into his throat and he couldn't breathe, couldn't beg Merlin. There was a smell of hair burning and then pain so great that he couldn't see for the agony of it covering his head, the back of his neck, and one cheek. He drew up his hand, and the skin where the fire had hit were bubbled and torment and everything was burning, and in that instant, Arthur knew he was going to die. "Merlin…." And Arthur began to curl forward, red and black and pain sheeting across him and….

"Gerín!"

A great wash of water poured down onto his face, glacial-cold, sending its own pain into his skin, and he couldn't breathe because he was drowning.

Tumbling down, past hissing wood, and steam and pain, trying to gasp air into starved lungs, Arthur barely could feel arms dragging him away from the flames, could barely understand that someone was cradling him. Shivering, overwhelmed with hurt and cold, all he could do was lay there.

He didn't dare open his eyes, didn't dare see how badly he was hurt. He didn't want to know. But more, he didn't want to know if it was Gaius who had rescued him, was holding him close. He didn't want to know that he had failed, that it was dark, and he had failed Merlin.

"You utter arse. You idiot, clotpoll, donkey-brained, cabbage-head. How dare you! How dare you!"

It sounded like Merlin, sniffling, grief's tears dripping onto Arthur's face. There were soft touches, so tender that they could have hardly been felt if not for the blisters of skin and char. On Arthur's other side, he could hear Gaius tutting, and then cold ointment smeared into Arthur's burns, hands gentle but firm. Cloth ripping and the smell of burned leather and linen.

As he drifted, above him were whispers and fury and contrite apologies. The sound of chanting and heat cooling into relief. He still didn't look up. His eyelids were sealed shut with more salve, but the voices were comfort and home and Merlin.

And that was good enough for now.

"Gerín!" = Rain

Geond bæl, geat onscíeteþ. Merlin, onierne sé geat ond edhwierfe. = Through the flames, the gate opens. Merlin, open the gate and return to me.