A/N: This story takes place after my story Intentions, which diverged from canon after series four. You'll have to read that story first (or PM me for a quick rundown) to understand this one as I pick it up almost immediately. As with last time, there's no slash, and any spells that show up over the course of the story will be taken from the Merlin wiki page.

Disclaimer: I don't own these characters, and I make no money from this work of fiction!

Arthur had never thought he would be a good actor.

He'd seen countless fools perform, watched various troupes enact stories, and listened to many a storyteller and minstrel in his time, but he'd never quite appreciated their talent before now.

He knew what it was like to steel himself for battle, to put on a brave face for the sake of the knights. For the sake of all of Camelot, really. But this was different.

This was…. This was a lie.

A constant lie.

He ate when he had no appetite, drank wine he never tasted. He smiled when it was called for and could even muster a laugh if necessary. He listened to the pleas of his people and handed out just rulings, oversaw the knights' training and suffered through council meetings. He made plans to tour through the outlying villages, he gave speeches, he arranged to host delegates from other kingdoms….

He did everything that was expected of him, but his heart wasn't in it.

His head wasn't in it.

He was hollow inside, merely going through the motions, wishing desperately that no one would notice.

Wishing that those who did would come up with a reason other than the truth upon which to lay the blame.

But although he was treated to a few lingering looks, no one confronted him.

Not even Gwen, although he suspected that might be because she believed she already knew the truth.

But she didn't.

Not all of it.

She wasn't sharing his pain.

She didn't have to live the same lie as he.

To be honest, Arthur wasn't sure how Merlin had managed to do it for so long. He'd thought Merlin was a terrible actor.

Of course, he'd also thought Merlin a terrible liar.

Arthur had thought this would be easier without Merlin around. He'd thought it would be easier if he didn't have to face Merlin every day. He thought he'd rather choke down a feast that tasted of nothing more to him than sawdust under George's watchful eye, no matter how fresh the fruit or how recently the bread had come from the ovens, than to have to eat whatever Merlin found him for breakfast.

He'd thought that things would be easier in the morning.

That, if the first morning remained difficult, the second would be better. That time would make the wounds less painful. That the distance between the present and the secrets of the past would somehow make everything seem less. Less important, less cutting, less real.

It didn't.

Nothing did.

Arthur had seen to it that Merlin had set off for home the morning after…everything. Merlin had protested, but Arthur had been firm, and eventually Merlin had agreed to pack his things. "Just for a few days," Merlin had said eventually, after a long evaluating stare that Arthur had found reminiscent of Gaius. "To give you time."

And because he hadn't seen his mother in a very long time, and because even Merlin knew better than to refuse the opportunity when Arthur had offered it. And, undoubtedly, because Merlin knew it was more of a command than a suggestion.

But Merlin was due back tonight, and Arthur hadn't had nearly enough time.

He hadn't even managed to come up with a good excuse to talk to Gaius alone. To get the facts straight.

And he still couldn't fight the sickening feeling that rose in his stomach whenever he thought of Merlin. Merlin, and all he was hiding. Merlin, and all he had done.

And Arthur knew he didn't even know half of it.

Yes, he was grateful, but….

But things would be so much easier if the truth wasn't the truth. That's part of the reason he'd never protested when Merlin had proposed…this. This lying, this pretending that nothing was wrong.

At the time, Arthur had told himself that his agreement on the matter was for the best of the people. Those in the castle, anyway, if not the rest of Camelot. This abstaining from telling the truth was to protect everyone else from the turmoil he was feeling.

It was better for Gwaine, for instance, to believe in Merlin's mask. To believe that the Merlin he thought he knew was the only Merlin there was. That Merlin wasn't hiding anything. If Gwaine found out that the man Arthur was quite sure he considered to be his best friend was a sorcerer, he'd….

Well, to be honest, Arthur wasn't quite sure what Gwaine would do. He wasn't quite sure what he himself was going to do, other than trying to get through another day without anyone else realizing the truth. But he did rather suspect that Gwaine's method of coping would involve a rather large amount of liquor.

A part of him wished he had the luxury of drinking away this…knowledge and all the stomach-churning feelings it brought with it.

But he was King Arthur of Camelot, and he needed to keep a clear head. Even in situations like these.

Merlin had promised to tell him the whole truth. He'd promised that he wouldn't keep things from Arthur, that he'd lay the truth out and let the king make his decree. But as much as he hated it, Arthur wasn't sure he could trust Merlin anymore. After all, Merlin had never said when he'd tell Arthur everything. What if he simply told him most of the truth? Or what if his slanted perspective unintentionally altered the truth of his stories? Arthur would never know.

There was a knock at the door, and Arthur closed his eyes to compose himself. It shouldn't be Merlin. He shouldn't be back yet.

Besides, Merlin might not even knock. He didn't always, even if he should. He barged in unannounced more often than he knocked, actually, so it really shouldn't be Merlin.

Although he might very well knock if he suspected Arthur to still be in the unsettled state he was.

"Come in," Arthur called.

Gaius entered, and Arthur let out a breath he hadn't realized he'd been holding. He rose to his feet, one hand automatically reaching out for the piece of parchment on the desk he'd been spending his hours staring at. He was certain Gaius knew he'd found out Merlin's secret—Merlin would surely have told him—but Arthur didn't want to relax, didn't want to let his guard down. He didn't want to slip up when someone else was around.

He didn't want to accidentally shatter the illusion that remained in place for everyone else, the one he now knew was far more fragile than he'd ever realized when he'd blissfully believed in it.

"I brought you something to calm your nerves, sire," Gaius said, holding out a vial of sickly yellow liquid.

Arthur had already rolled up the parchment, effectively hiding from stray eyes the list he'd made that had helped him realize the truth, so it was easy for him to take the vial from Gaius with his free hand. "I'm not sure I want this," he admitted.

"It will help," Gaius said simply.

"But I'm not—" Arthur broke off his protests, not feeling up to more lying—especially not under Gaius's stare. "I can't afford," he said instead, "to relax my guard."

"It isn't very strong," Gaius informed him reproachfully. "It will not cloud your mind. It will simply relax you enough so that you do not jump at every little sound. Do not think people have not noticed the change in you, sire."

Perhaps he wasn't as good an actor as he'd thought.

But he was the king, and people didn't question him. Not in minor matters such as this. But if he ever tried to do what he must to ensure Merlin's safety if he continued to stay in Camelot, if he so much as mentioned even thinking about retracting the laws banning sorcery….

Arthur dropped the parchment roll on his desk and met Gaius's gaze. "How," he asked, "can you just stand there, calm as ever, knowing that Merlin—?" He couldn't say it.

Gaius looked at Arthur for a long moment. Then, in a quiet voice, Gaius answered, "Before I even properly met Merlin, he saved me from grave injury. His heart always has been and always will be in the right place. You have no more need to fear his magic than you do to fear him, and you know that Merlin would happily give his life for you."

Arthur pulled a face. "I know Merlin's been…. I know what he's done in the past. I just…."

"The future," Gaius pointed out, "will be no different."

"You can't know that," Arthur argued softly.

Gaius's gaze didn't waver. "I do. I know Merlin. That will not change."

This was the conversation Arthur had wanted to have with Gaius, but he didn't feel…ready for it, perhaps. He kept glancing at the closed doors, trying to assure himself that no one else was listening. Even if someone was, they were speaking too softly to be overheard.

Perhaps he ought to drink Gaius's concoction after all.

"So Merlin's never—?"

"Merlin is as loyal to you as I," Gaius replied. "You should not doubt him."

"I don't…want to," Arthur confessed. "But I just…. How can I not? He's lied, Gaius. For years. I never had any inkling of it until now. If he starts again—"

"I will tell you," Gaius said.

There was nothing in Gaius's tone that suggested otherwise. There was nothing that hinted that he might merely be saying what Arthur wanted to hear.

But Arthur hadn't been able to tell that Gaius was lying when he'd said, in much the same tone, that he did not know Emrys. Gaius was loyal to Camelot. Arthur knew that. He'd sworn he'd never mistrust Gaius again once it turned out that Agravaine had been the traitor all along.

But Gaius was loyal to Merlin, the boy he thought of as his son. Gaius would protect him—had protected him—from Arthur. Of course he'd sing Merlin's praises and vouch for him. But Gaius would never risk Camelot. He trusted Merlin, trusted that Merlin would never become a threat, even inadvertently.

Arthur was still trying to figure out if he could trust either of them, at least where the issue of magic was concerned.

Had Gaius been teaching Merlin all this time?

Or had that been this…Kilgharrah person Merlin had mentioned?

As much as he'd hated not knowing, there was still a part of him that wished he'd never put on that blasted pendant. If he'd been a bit more like his father, too wary of anything magical to even consider its use….

But if he'd been a bit more like Uther, Merlin wouldn't be on his way back to Camelot at this very moment. If he hadn't been banished, he'd be in the dungeons awaiting a public execution. For crimes of sorcery. Assuming he didn't use said sorcery to escape and leave Camelot behind forever.

The thought made Arthur feel ill.

Merlin had nearly gotten himself burned at the stake for using magic. Twice, if Arthur counted the time he'd idiotically confessed to it. And he'd risked it…. He'd risked it countless times.

He'd drunk poison and been prepared to do it again—or, at least, what they'd thought had been poison. He'd followed Arthur out to fight a dragon. He'd thrown himself in front of the Dorocha. He'd…. There were so many times Arthur knew he'd foolishly risked his life, times magic wouldn't have helped him.

So perhaps Merlin's intentions were noble and would never change. Perhaps Arthur had him to thank not only for his life and Guinevere's but also for practically every one of his knights' and, undoubtedly, most of the citizens in his kingdom. But none of that would have made a difference to Uther. Uther would have had Merlin killed, calling Arthur enchanted if he so much as spoke a word in Merlin's defence.

So perhaps Morgana was right after all, on one level.

Uther had blindly slaughtered anyone associated with magic.

He had raised Arthur to do the same. Arthur had done the same, even when he'd tried to spare the women and children. He'd known that long before he'd been forced to admit it to the ghost boy at the shrine.

To Merlin, who'd known all about the dangers of disturbing that shrine. Because he had magic, no doubt. Merlin was a powerful sorcerer. He could probably sense it. It would explain why he invariably managed to pick up on anyone who was up to no good and was always proven right in the end, even if Arthur never believed him at first.

But if Uther had been wrong to outlaw sorcery, how many innocents had died? How much blood had been shed in the name of peace? How much was on Arthur's own hands?

How much of his kingdom was built on a lie, and how would he keep it from collapsing if he started to relax the laws on magic?

Should he even take the risk now? Just for Merlin? Merlin, who had already proven himself more than capable of hiding?

He'd thought the easiest thing would be to do nothing. He knew it cowardly—he ought to act—but he'd reasoned that Merlin deserved to have time to prove himself. Merlin had thought the easiest thing would be for Arthur to banish him. That's why he'd taunted Arthur that he should do what's right and not what's easy.

But according to the laws, sorcerers should be executed. That's what was right, and that was certainly not easy. But the law had read the same for Guinevere's unfaithfulness, and Arthur had seen her banished, and Merlin had clearly feared Arthur would reach the same decision for him. And feared, as Arthur had seen, that he wouldn't be able to protect Camelot if he wasn't there.

It shouldn't be so hard to trust Merlin.

But it was.

And even knowing that Gaius, loyal as he was to Arthur, would put Merlin's protection first if it didn't directly appear to harm Camelot…. What if Merlin did turn against him or was turned against him, even if it wasn't of his own free will? He knew Morgana practiced dark magic. There had to be something that could rob someone of their senses like that. What if Merlin fell prey and Gaius thought it best to deal with the matter in his own way without informing Arthur?

What if Gaius failed?

Merlin was powerful.

Arthur, who had seen him close to death an uncomfortable number of times, knew he was far from invincible.

Having magic did not mean one was protected from everything.

If someone managed to fool Merlin into thinking he was doing something good and he didn't realize the truth until too late….

Merlin didn't deserve to have such a responsibility hanging over his head. Arthur was the one who needed to be ever-aware for the sake of his kingdom. Arguably, it was better for Merlin if Arthur didn't allow him to stay. He wouldn't have to worry about being the one who unwittingly brought about the end of the kingdom—from within, no less.

Of course, Merlin was more stubborn than an ass, and he'd never see the logic of it.

And Arthur felt less…. He wasn't as comfortable with ordering Merlin about as he used to be. Telling him to go home to visit his mother…. That had been different. That wasn't something Merlin would protest. Arthur knew Merlin wouldn't mind doing that. He would even enjoy it, for all that he wouldn't have appreciated the timing.

But now that he knew Arthur knew about his magic, maybe he wouldn't…. Maybe he wouldn't be so hesitant to use it in front of him when it was just the two of them. Maybe he wouldn't abstain from using it on Arthur himself if he wasn't afraid that doing so would mean Arthur would find out. Maybe—

But this was Merlin.

Merlin had not, in the past, shown any inclination of taking over Camelot, of having Arthur acting as a mere puppet to his will.

Of course, he'd never shown any talent for much of anything before, either.

Well, Arthur supposed he was moderately learned in the healing arts.

Still. Merlin. The thought shouldn't even be crossing Arthur's mind.

But Merlin is a sorcerer. A warlock, he'd said. Because he'd been born with magic.

Even though Arthur didn't want to admit it, he felt that just made things worse.

He should never have put on that blasted Stone of Æthelu.

If he hadn't, if he'd given up his search for Emrys, he wouldn't have to be dealing with…this. He could still be believing in the lie like everyone else. And Merlin would just be Merlin, and Arthur could trust him with his life.

But it was better this way, even if it didn't seem like it. Because this meant things weren't going on behind his back and under his nose. This meant he could judge things fairly. He could be confident in his decisions.

In theory.

He wanted to give Merlin a chance to explain himself. Merlin's actions in the past seemed to warrant that. But Arthur wasn't sure how much time Merlin would ask for, and he had a terrible feeling that Merlin would try to extend it until he could convince Arthur to change Camelot's laws.

As if that were an easy thing to do.

Merlin always tried to see the bright side of things. Arthur had always thought it a somewhat endearing quality. But now he wasn't so sure how much of Merlin's optimism was real. He wasn't sure how much of the Merlin he knew was real. Merlin said that his magic was the only thing he'd kept from Arthur, but Arthur couldn't bring himself to believe that.

That was too easy, for Merlin's magic to be his only secret. Arthur could see that now that he'd had time to think. Merlin was prone to wishful thinking, to underestimating things verbally even if he understood the gravity of the situation; Arthur knew that. But he'd also learned, unfortunately, that Merlin was awfully good at telling half truths.

Arthur wasn't sure he could tell the difference anymore.

He wasn't sure if he'd ever been able to.

"It isn't that simple, Gaius," Arthur said at last. "I can't…. I'm harbouring a sorcerer!"

"Merlin is your friend, Arthur," Gaius said firmly. "Everyone knows that, even if you do not freely admit it. And it is something you yourself must know, as it is that friendship which has kept you from acting against him."

Gaius believed in Merlin. Arthur could see that. He could say with complete confidence that Merlin would never move against Camelot. That he was clever enough—Merlin, clever enough!—to avoid even being tricked into it. But Arthur didn't have that confidence.

It had been shattered the moment Arthur had realized Merlin possessed magic. That Merlin was a sorcerer. That Merlin was Emrys.

There was a small part of him that found the entire affair laughable. Merlin, in a position of power? Merlin, with any power? It was Merlin. The idea was ridiculous.

Except that it was very, very real, and that drained all the humour from the situation.

He wished he could send Merlin away again when he returned, but unless he was incredibly lucky and Gaius had to send him out gathering herbs or some such thing for the entire day, he'd have to face him.

He'd have to look him in the eye, knowing…knowing everything.

Well.

Knowing almost everything.

Enough, at any rate, to know that this wouldn't last, that theirs was a tentative state which would be easily broken. That the illusion, now that he was aware of it, would never fool him again. That it was far too late to stop, to turn back and take a different path. There was no way to go but forward.

Arthur took a slow breath. "How many people have noticed, Gaius?"

Gaius, wise as he was, knew Arthur was not questioning how widespread the knowledge of his friendship with Merlin was. He did not clarify his answer, but Arthur knew exactly what he meant. "All those closest to you."

Those closest to him.

Gwen. Gaius. His most trusted knights: Leon, Percival, Gwaine, and Elyan. They all knew something was wrong, that something had him on edge. Of those, Gaius knew the truth. Gaius and Merlin, Arthur supposed. Guinevere certainly suspected it, and she knew half the story, but he trusted that she had said nothing to anyone else, not even to Elyan. Meaning the knights would merely be guessing themselves.

He'd have to allay their fears. It wouldn't do to have them shooting significant glances behind his back. He didn't need people to start whispering. It would be hard enough to ensure that didn't happen once Merlin returned; he certainly didn't need it beginning already.

"And beyond them?"

"Nothing of note, sire. You have not quite been yourself since you began your search for Emrys. People merely presume that you are still desperate to find him."

He'd been less himself since he'd found Emrys, but it was better for the people not to know that. In a day or two more, he could drop the façade altogether. It would be more than long enough by then to admit that their resources best be put to other matters. Tracking Morgana's movements, for instance. Something else could eclipse his attention, and he could officially close the matter for the time being without the people being any the wiser.

That way, it would be less an outright lie and more a withholding of information for the time being.

Arthur's stomach twisted at the thought of that justification for lying to his people. A small part of him wondered if this is how Morgana had felt when she'd been fooling the kingdom into thinking she was nothing more than Uther's loving ward, restored at last to his side after a harrowing experience that was too trying to speak of. It was unlikely; by then, from what Emrys—Merlin—had said, Morgana had already completely turned against Camelot.

Morgana's treachery was something else that Arthur hadn't seen until it was far too late.

Arthur couldn't help but wonder if he'd known about her earlier, if he'd noticed—or if Merlin had told him and proven his claims—if anything could have been done. So that Morgana wouldn't have been swept down such a corrupt path. He could have helped her, perhaps. They could have still been friends.

But Arthur wasn't so sure his support would have been enough.

He knew his father as well as Morgana did. "Morgana would have been put to death by Uther if she had been discovered," Em—Merlin had said.

The knowledge made Arthur's heart ache, for he knew it to be true enough. Uther had been heartbroken by Morgana's treachery, especially once it had become more evident that she was not merely acting as Morgause's puppet. He had loved her, blindly, as the daughter she was. Sorcery, however…. That ignited a fury in Uther that blinded him to everything else, and certainly by the time they'd realized the truth of it, Morgana had been beyond saving.

But Morgana…. In light of what she'd become, his father—their father—had been proven right. People like her were the reason Uther had instigated the laws! To prevent this. If she had been discovered and put to death….

Things would be different.

He knew better than to assume it would be better. Camelot would be facing a new threat—there seemed to be no shortage of them—and it could well be as formidable as the one Morgana posed. But would the risk of destruction be the same? Would it still be magical in nature?

Would it still be something fuelled by Camelot's bans on sorcery?

Arthur allowed his shoulders to sag, just slightly. This was Gaius. Gaius was one of the few people who could look easily behind his masks. "Good," he said, not bothering to hide the weariness in his voice. He wished this were over, but it wouldn't be, not for him, even if it seemed to be over for everyone else.

Everyone still caught in the illusion, anyway.

"Best take that now, sire," Gaius said, eyeing the remedy Arthur was still clutching. "It will not take me long to prepare another if you desire it."

"Yes, of course," Arthur said automatically, though he made no move to take the concoction. Later. Right now, he needed to think. "Thank you, Gaius. That will be all."

Gaius bowed his head and took his leave, and Arthur stared at the door long after Gaius left. He'd holed himself up in his chambers after he'd concluded his most important duties—the ones he couldn't pass off to others, at any rate—as he had done every day since he'd discovered Merlin's…. Since he'd discovered Merlin. He wanted to keep up appearances.

But it was…. He'd faced down a dragon, but this almost seemed…harder. Less certain.

Especially since he knew that the next time his doors opened, it might be Merlin. Back from Ealdor, back from visiting his mother, and, as far as everyone else in the castle was concerned, ready to resume his usual duties as if he'd never left.

But it wouldn't be like that at all.

It would never be like that again.

Because Merlin wasn't just Merlin. He was also someone else, someone Arthur didn't know and couldn't trust, and…. And he had to pretend that that other Merlin didn't exist, all for the sake of the kingdom, just long enough to hear Merlin out, and then he'd have to…. He'd have to….

Arthur sighed, wrenched open the vial, downed Gaius's mixture, and closed his eyes.