I don't own Merlin.

I have no idea if this has been done before, but the idea came to me when I was watching "The Death Song of Uther Pendragon". Hence the title. I do want to put in a warning for mention of a suicide attempt. Other than that, nothing but pure, soul-shattering angst. That's the intention, anyway. Enjoy!

Deep beneath the citadel of Camelot, Merlin stood, turning a curved piece of ivory over in his hands and watching the torchlight flicker over the delicate carvings around the top. He hadn't seen this artifact since the last time he had seen Uther Pendragon; he remembered the sweet, mournful tone it played when it touched the young king's lips, all the pain it had brought lingering beyond the banishment of Uther's spirit. The way his eyes glistened with unshed tears and Merlin's heart raced at the near revelation of his secret. Maybe, if he had waited just a second before blowing the horn, things would have turned out differently. Maybe, if Merlin's magic had been revealed sooner, the warlock wouldn't have been so helpless when the king marched to Camlann. Maybe, if he had accepted Merlin's magic, he wouldn't have fought at Camlann at all. Maybe-

"What's that?"

Merlin started. For a moment he thought to hide the horn, and his mind flashed back to a bowlful of apples tumbling to the floor, the empty bowl overturned on the table in front of his king. The corners of his lips twitched up in the ghost of a smile.

"It's nothing."

Gwen skirted around a pile of objects, both magical and non-, and leveled her eyes with Merlin's. "I often wonder," she chided, "how you managed to survive ten years here, as poor a liar as you are."

"It's only because you lot were so terrible at seeing the truth." He turned to place the horn back where he found it, on a table against the vault's stone wall. "It really is nothing, I promise."

Gwen's hand shot out and intercepted Merlin's, gingerly removing the horn from his grip. She studied it without recognition. "Is it magic?" Merlin nodded. "Powerful?" Another nod. "What does it do? Or rather, what did he do with it?"

Merlin flinched, then pretended Gwen hadn't noticed. She fixed her doe eyes on his and began drawing the answer out of him. All his magic, and he couldn't resist the queen's soft gaze. "It's a horn," he replied, opting to answer the first question, "used by the high priestesses to talk to spirits of the dead." His eyes flicked down to the floor; he did not want to see her reaction.

"That sounds very dangerous." Her voice was level. Merlin kept his eyes trained on the ground. "Why would he keep something like this down here without telling me about it?"

Merlin sighed. He couldn't keep her in the dark forever; he might as well tell her now. "Because of what happened when he used it."

The echoing crash as the chandelier collapsed onto the round table. The smell of smoke; Camelot's king had almost lost his wife that day, and his best friend. The fury painted across one king's face, the betrayal painted on another's. Merlin had hoped he would never see the Horn of Cathbhadh again.

"What happened?"

So he told her. How the young ruler had been so desperate for guidance, for approval. How in the weeks following he had slowly come to terms with what it meant to let his father down. How none of it mattered in the end.

Guinevere listened in silence until he finished. When the story ended, she said only, "That must have been difficult." She didn't need to add, for both of you.

"It was."

They let that hang in the air for a moment before Gwen set the horn on the table and returned to the pile she had been sorting through. Merlin stared at it, then picked it up again. "I only thought…"

"Yes?"

"You might want it."

She turned back to face him. A tiny smile brushed her lips despite the deep sorrow etched across her face. "What use would I have for that?" she asked innocently.

"Is there no one you would talk to, if you had the chance?"

The vault was silent again. Gwen crossed the room and laid a hand on Merlin's arm. The smile was gone. "Not a day goes by when I don't miss him, Merlin. I think about him all the time." She glanced down at the horn in his hand, then back up at him. "But I've made my peace. I've moved on."

Merlin's shoulders sagged. "Then I should do the same?"

Gwen lowered her hand to the horn and curled Merlin's fingers tightly around its slender neck. "I think you should do whatever you feel is right." She brought his hands, still gripping the horn, up into the space between their chests. The smile returned for a moment. "You haven't been the same since you came back from Avalon. To be quite honest, I miss you just as much as I miss him."

Merlin nodded, and Gwen released his hands. "You should retire," she said. "You've been down here for far too long. Go see Gaius, or take a ride, or practice your spells. I can keep working for now."

"Sorting through magical artifacts? Without me?"

"Then I'll retire too." She took a step toward the iron door leading to the stairs, then turned and gestured back to Merlin.

After a moment, he relented. "Yeah, alright."

"You know how dangerous it is, Merlin." Gaius's back was turned to the warlock as he worked on a potion.

Dangerous. Merlin nearly scoffed at the word. He had spent ten years in constant danger, persistent fear. Now Morgana was dead and magic was once again free in Camelot. Merlin had never been so miserable.

"Maybe that's why I want to go."

Gaius turned and shook his head at his ward. The lines on his face had deepened recently, and his hair was now long past his shoulders. A constant reminder that Merlin wasn't the only one who suffered the loss. "It's been nearly two months, my boy," he reprimanded softly. "Did you really enjoy risking your safety that much, that you can't sit still for this long?"

"For him? More than anything."

"I would not attempt it-"

"I didn't come to ask your permission!"

"-but I think you may not have a choice."

Merlin froze, his eyebrows knitting together. He could not find the words to respond, stunned as he was at Gaius's admission.

"Do not think I have not noticed the toll these last few months have taken on you," the physician continued. "You hardly sleep, you slouch when you stand, your face has gone grey. This is easily the longest conversation I've had with you in a long time. And I haven't heard you laugh since-"

"I know."

"All the light is gone from your eyes." Merlin slumped down onto the cot in the middle of Gaius's workroom and put his head in his hands. He knew he had been...different...these last two months, but he hadn't realized the effect it had on the people around him. He was wallowing in regret.

"Guinevere, the knights, myself-we have come to terms with what happened," Gaius said. "The whole of Camelot is beginning to look forward again." Merlin nodded slowly.

"I'll leave tomorrow morning," he said curtly. "Alone."

"The last of the Saxons were taken care of weeks ago. You will be safe." Merlin nodded again. "Still," Gaius added, "promise me you will be careful."

Merlin knew the warning was not for the journey, but for what would happen when he reached his destination.

"I promise."

When the stones appeared over the crest of a grassy hill, the image gripped Merlin's heart like ice. Nothing had changed-not that he expected it to. Still, he had to fight the urge to turn his head to look at the king that should be riding next to him. But the only hoofbeats he heard were his own horse's.

Time, he found, had divided itself into two eras: a before and an after. The before seemed eons past; a distant memory, like a past life or a fading dream. The after was a dark expanse that stretched infinitely before him. And for Merlin, it seemed, it truly was infinite.

Over the past two months, he had taken up painting, trying in vain to capture the image of his lost king. How long did it take to forget a face? But despite his ineptitude at art, Merlin doubted he would ever erase his last image of the king from his mind; the young warrior's body laid peacefully in a boat, his blue eyes closed forever.

In the spirit world, would his eyes still be so brilliantly blue? Would his hair shine like the sun the way it did when last Merlin had seen these stones?

Merlin reached the ancient monument and dismounted, whispering a spell to keep his horse from wandering off. Its saddlebags were empty; the horn was stowed in Merlin's satchel, which he wore across his chest and kept tucked close to his body. It was necessary that he protect the horn carefully. It contained powerful magic, but to Merlin, it meant more than that. The horn was his one chance at forgiveness, his only chance to see his best friend again and apologize for failing him in the worst way.

Slowly, hesitant but determined, Merlin approached the center of the monument. He drew the horn from his bag and held it up to the sunlight. Its polished surface shone under the cloudless sky. Was this really what Merlin wanted? Before he could answer himself, he closed his eyes and raised the mouthpiece to his lips.

And he blew.

Blinding light. It was all around him and inside him. He could not tell if his eyes were open or closed anymore, because whatever he did, the blue-white light penetrated his vision. Then it began to fade, and a shadow appeared in the distance. A shadow shaped like a man.

"Arthur."

It was the first time he had spoken or heard the name in two months, a breath on his lips barely audible, were it not for the eerie silence of this semblance of the spirit world. He knew that people had been saying the name from the day Merlin arrived from the lake, but they always seemed to avoid it around him. Too painful, they assumed. It will pass, they believed. He had thought about nothing but the king since his death, and yet he couldn't even bring himself to speak his name.

"Arthur," he said again.

The figure slowly came into focus. "You look like you've been sleeping in the stables."

"I think I'm doing a bit better than you."

Arthur was bathed in an ethereal blue light that shone off his fair hair and tanned skin unnaturally. He wore his armor and red cape, which rippled and shimmered despite the stillness of the air around them. Merlin felt his heart lurch; the king looked just as he had when he had collapsed in Merlin's arms, only stronger, more sure.

He studied Merlin closely, his eyes narrowing. "I don't think that's true," he said.

Merlin chuckled humorlessly. "Well, you're obviously in a good mood. I haven't seen you in two months and the first thing you do is insult my looks."

Arthur's face remained sober. "Two months," he mused. "I wondered when you would find that horn. I had hoped you'd have the sense not to use it." His face broke into a wide smile. "I'm glad you did."

"I've missed you." Merlin said, fighting the tears that began to burn his eyes. "Everything is different."

"Tell me."

Merlin began, "I'm a lord now."

"Only two months and already the kingdom's gone mad?" Arthur quipped. "Whose idea was it? Guinevere's?" Merlin nodded. "She always was the sensible one."

"Please," Merlin teased back, "you'd never do it yourself. The only reason I took the title was because I got bored with no one's armor to polish."

Arthur huffed. "Lord Merlin."

"Sounds foolish, I know."

"Why did she do it? To thank you?"

Merlin hesitated for a moment. "She...wanted a Court Sorcerer to aid in the return of magic to the kingdom. Court Sorcerer, that's...that's my official title."

Arthur's head spun. He was brought back to a time where he stood in this place, on the other side of the veil, speaking with his father about the changes he had made to the kingdom. If Uther saw him now…

"You'd be proud of Gwen." Merlin hastened to change the subject. "There have been peace talks, and already-"

"So the ban has finally been repealed." It was not a question.

Merlin resisted the urge to hang his head. He settled for casting his eyes to his feet, not even daring to imagine the reaction on the king's face. But his mind couldn't help but linger on one single word. Finally...the ban has finally been repealed... "Yes."

"All the time you've spent in Camelot, this is what you've been waiting for."

The Once and Future King and Emrys...unite the lands of Albion… "Yes."

"I only wish I could be there to see it."

Merlin's gaze shot up to meet Arthur's, and again he felt the sting of unshed tears.

"I'm so sorry," Arthur said.

"It's not your fault," Merlin replied automatically. "You didn't choose to-"

"Not that." Arthur took a tentative step toward Merlin and knit his eyebrows. "For ten years you lied to me, kept such an important part of yourself hidden. All those years, and you never trusted me enough to feel that you could be honest. It took my death for you to stop hiding. For that, you have only me to blame."

"I'm the one to blame," Merlin said, clenching his fists at his sides. "All my power, and I couldn't save what mattered most in the end."

Silence. Arthur slowly shook his head. "How can you say that? That I mattered most to you? It's only now that I'm dead that you can truly be happy. What kind of a king...what kind of a friend does that make me?"

"You're wrong." Arthur quirked an eyebrow, and Merlin continued, the shadows under his eyes seeming to deepen with every word. "It's true, that magic is legal now. We've achieved so much peace in so little time, and I am honored to be a part of that. Gaius is practicing healing magic once again, and I've taken on several magical apprentices. I haven't spoken a single lie since…" He trailed off, afraid to finish the thought. "Everything is as I had always dreamed. But I've never been more miserable in my life.

"There are mornings when I wake up to the sun streaming through my windows and I panic, thinking of the shouting I'll get for being late with your breakfast. It always takes me a moment to realize I'm in my own, private chambers now, and there's no breakfast to be fetched. Sometimes, if Gwen and I are going for a ride, I'll accidentally saddle two horses instead of one. She'll try and send away the stable boy with her horse so she can mount my extra, because she knows." His lip quivered and his eyes grew red, but he didn't stop. "And your chambers. They've been left empty, locked, but I don't need a key to get in. And I do. I remember the last time we were in there together. You said-"

"I always thought you were the bravest man I ever met."

"But you were wrong."

"No," Arthur said. "Never. I only said that because I was hurt." He paused for a moment, considering. "Why didn't you come with me to Camlann?"

Merlin sighed. "Morgana found out about my magic, and did something to it. Stole it from me. I had to go to the Crystal Caves to get it back."

"And you did."

He nodded. "It hasn't been the same since…"

"Since what?" Arthur suddenly snapped. "Since what? It's been two months, and you won't acknowledge, to my face as we speak through the veil to the spirit world, that I'm dead?"

Merlin flinched at the word. It was true. Not only had he avoided mention of the king's name since his passing, he had also avoided all conscious thought regarding the events on the shore of Avalon. Nevermind that every time he closed his eyes the lifeless eyes of his best friend stared back at him. Nevermind that his heart leapt at every glint of gold he saw, only to sink deeper than the dragon's cave beneath the citadel. Nevermind that he avoided the color red at all costs in his own strange way of mourning. If he refused to recall his greatest failure, maybe he could keep himself teetering on the brink of insanity without tumbling headfirst into a downward spiral that led who-knows-where. It had worked so far, hadn't it?

Guilt clawed at Arthur's heart. He had touched a nerve and he knew it. What right did he have to prod a grieving man, even if he was the very object of grief? But he knew, deep down, that something wasn't right with Merlin. The eyes that he remembered, the last thing he saw before the world went dark forever, had sparkled with mischief, kindness, pride, and later, the golden gleam of magic. Now they were dull and painful to look at. The rims were puffy, as though the sorcerer spent all of his time rubbing at them or biting back tears. The lids were heavy with a darkness that spoke of troubled sleep. Merlin looked almost like a reanimated corpse.

"Do you remember," Arthur began tentatively, "when I told you that no man is worth your tears?" Merlin nodded almost imperceptibly. "Did you cry for me?"

The bluntness of the question pierced Merlin's chest like a knife. "On the shore, right after you…"

"Died."

"yeah, I, er, I cried then. But since then...no. Not once."

Arthur turned his gaze from Merlin, staring off at something distant that only he could see. "From the moment I told you that, I regretted it. I wanted to tell you I was wrong, that bottling up your emotions doesn't make you stronger. I never had the courage."

Merlin blinked, and Arthur could see the tears pooling on his bottom eyelid, threatening to spill over. Merlin blinked again. Even now, face to face with Arthur, he couldn't let his emotions show.

"Tell me more about Camelot," Arthur blurted, opting to change the subject. "So magic is practiced freely within its walls?" Merlin nodded, and Arthur chuckled at a sudden thought. "I bet Gwaine's loving that. Opens up a whole new world of mischief and practical-"

"Gwaine's dead."

Arthur's face fell. "Oh," he said, at a complete loss for words.

Merlin wore an unreadable expression; blank and calculated, void of all emotion. "He and Percival set out to try and kill Morgana. She caught them and tortured him to death. That was just before I killed her."

"You don't seem to be having much trouble talking about his death. Or hers."

"I'm sorry." That was all he could say. What was he supposed to tell the king? Gwaine's death had hit him hard, yes, and not a day went by when he wished he could just sit down at the tavern and laugh over a pint of ale. But there was nothing he could have done to save his friend. And Morgana...in Merlin's eyes she had died long ago, leaving only a hollow shell made of nothing but hatred and revenge. He had come to terms with their losses, however painful they had been.

Arthur was a different matter. When Merlin lost Arthur, he lost his purpose. Yes, he loved Gaius and Gwen and all of the knights, but his magic and his life had been marked out for one person and one person alone. The Once and Future King. Since returning from the lake, his magic was considerably weaker. He knew his power was still there, but he lacked the motivation to access it. Without Arthur, nothing was worth it. Without Arthur, his life was meaningless.

"I know you've used magic to save my life more times than anyone can count," Arthur said in a low voice, "and for that I am eternally grateful. But do you know how many times I put my life on the line to save yours?"

"I don't underst-"

"Listen. My father was fond of reminding me that your life wasn't worthless, but it was worth less than mine. Nothing could be further from the truth. You were always one of the most important things to me, and I would die a thousand times over before letting any harm come to you. If I could have my life back, I would gladly give it up again to see you safe and happy."

"But I'm not happy. I haven't been since the day you…" Arthur's eyes sparkled, and for the first time in two months Merlin felt himself let go. "...died."

"What can I do to fix that?"

Merlin smiled weakly. "Come back?"

Arthur chuckled, expecting Merlin to do the same. When he realized Merlin wasn't joking, his eyes narrowed in confusion. "You know I can't-"

"There's something you don't know," Merlin said. His eyes were closed. "Something I didn't know until very recently."

He hesitated, breathing deeply. "Yes?" Arthur prompted.

"A prophecy. An ancient legend. Emrys and the Once and Future King, who will unite the kingdoms of Albion. These last few years, your time on the throne, was the Once. The prophecies say that when Albion's time of greatest need comes, the king will rise to complete the Future of his destiny. And Emrys…"

"What?" Arthur said, barely above a whisper. "What about Emrys?"

"Waits."

Arthur shook his head. "I don't understand."

"The Once and Future King will rise again when Albion needs him most. And until that time, be it a year from now or a century...I cannot die."

The silence hung between them like glass, heavy but fragile. For a moment, neither of them dared to speak. Then Arthur huffed. "Rubbish. An old wives tale. You know how fond the druids are of mystery and secret."

"It's true," Merlin said, refusing to meet Arthur's eye.

"How can you know that?"

"Because that day, after I sent you to Avalon...I tried to kill myself."

His words wrapped Arthur's heart in an icy grip. Merlin-gentle, kind, clumsy, cheerful, wise-beyond-his-years Merlin-had tried to take his own life on Arthur's account. Only to find that he couldn't, not until some mysterious day far into the future when Arthur came back from the dead. It was surreal.

A hot tear traced a line down Arthur's cheek. Vaguely, he wondered at the revelation that the dead could, in fact, cry for the living. "I'm so sorry," he choked.

Merlin lost his control. Finally, after two months of holding on, he felt his face grow wet with tears. His hands twitched to wipe them away but Merlin held them firmly at his sides, intent on finally letting himself feel the loss of his best friend. "I'm sorry too."

They let their tears fall together, never taking their eyes off each other. When Arthur felt the telltale sting in his eyes, the feeling that they had nothing left to give, he drew his hands across his cheeks. "I want you to promise me something, Merlin," he said. Merlin took a shaky breath and nodded. "However far away that day is, when I return, promise me that until then you will be let yourself be happy."

"I don't-"

"Promise me."

Merlin could see the desperation in his friend's wide eyes. He studied them, the depth of their honest, crystalline blue. Eyes that had seen so much and still remained so pure in intent and emotion. The eyes of a king and a friend. "I promise."

Arthur's face broke into a wide smile, and Merlin couldn't help but smile back. "Then let me say something I think you need to hear. Something that will set you free, allow you to keep your promise when you return to Camelot."

The air around them seemed to shift as Arthur began retreating back to the spirit world. Merlin's smile faltered; he wasn't ready to leave his friend, not yet. Not until the king's final three words resonated through the strange space like an echo coming from all sides.

"I forgive you."

Merlin turned and took a few steps back toward the mortal world. Then he froze. The coming years would not be easy. He had no idea how long he would have to wait for Arthur's return, or how much pain and heartache he would suffer until that day. But one thing was certain.

The king would return. And until he did, Merlin would live with his blessing and his forgiveness.

Merlin took another step. Then another. The first of many steps through a difficult future. Arthur's words rang through his head like a mantra, guiding him along as he pushed himself forward.

And for the first time in two months, he didn't look back.