A/N: As usual, I am far too late, and I apologize. I'm running into some difficulties with the story, and I might go back and make some minor adjustments so it's a little more believable.

I'll put some more notes at the bottom; for now, enjoy.

CHAPTER FIVE

Naturally, Gaius was suspicious.

"I'm fine," Merlin tried to assure him yet again. "I probably just fell asleep. Nothing to worry about."

To nobody's surprise, Gaius had one eyebrow raised menacingly. "Gwen sounded very concerned."

"You know how girls are," Merlin said. "She saw me on the ground and assumed the worst. Frankly, I'm offended that she didn't believe me when I said I was fine."

Arthur snorted, and Merlin had to force himself not to turn around and glare at the prince.

"You always say you're fine," Gaius pointed out. "Even when it's not true. And she knows it."

Merlin sighed. Gaius was a difficult person to deceive, and he somehow always knew when Merlin was lying to him. It was uncanny. And frustrating.

"Also," Gaius continued, "it seemed that she had been specifically searching for me throughout the castle, when we both know I was in town. Any idea who could have told her to look there?"

"Not a clue."

Gaius glared at Merlin. Merlin smiled blandly back. Arthur crossed his arms and sighed.

"Merlin," Gaius said sternly, "what did you do?"

"Nothing."

"If you used magic—"

"I didn't!"

The denial was too quick, and they both knew it. Merlin cringed internally as he saw Gaius narrow his eyes, but it was Arthur who spoke first.

"Wait—Gaius knows?"

Merlin risked a glance in his direction, and saw that the prince looked flabbergasted.

Great.

"Whatever you did," Gaius said, oblivious to Arthur's outrage, "it better not have been something stupid and dangerous."

"When have I ever done anything stupid and dangerous?" Merlin retorted automatically, still distracted by the look on Arthur's face. He could tell the prince was thinking deeply, and if it weren't for Gaius, he would have snapped at Arthur to stop before he caused himself injury.

Gaius glared at him again, and his brain finally caught up with what he'd said.

"Fine. Don't answer that. But at least I always know what I'm doing."

Gaius sighed. "I'll ask you one more time, Merlin. Did you use magic while I was out?"

"Hold on," Arthur cut in. Being the self-centered prat that he was, he didn't seem to care that Merlin was busy trying to hold a conversation with Gaius. "If Gaius knows about your magic, then why are you lying to him?"

Merlin hesitated. Loathe though he was to admit it, Arthur had a point—he didn't have to lie to Gaius. But he usually tried not to involve his mentor in these things unless it was absolutely necessary, both to save Gaius from being caught up in something terribly illegal, and to save himself from one of Gaius' infamous lectures.

"I'm offended, Gaius," he finally said. "I already said that I didn't. You people have so little faith in me." He shook his head like he couldn't believe that Gaius would doubt him.

"You are one of the most irritating people I've ever met," Arthur informed him sourly.

The look that Gaius was sending him suggested that he felt similarly, but the old physician knew how to recognize a lost cause. He let out a resigned sigh, although Merlin had a feeling that the subject might come up again later.

"Make sure you go to bed early tonight," Gaius said, walking past Merlin to replace the contents of his bag to their proper shelves. "Did you at least make any progress on Arthur's condition before you collapsed?"

Arthur gave Merlin a pointed look.

"No, I, uh… I think I fell asleep pretty soon after you left."

"Tell him," Arthur said, putting his hands on his hips. Merlin made a shushing motion at the prince while Gaius had his back turned.

"Don't worry, we'll keep looking," Gaius said absentmindedly, still fussing with some bottles.

"Tell him."

Be quiet, Merlin mouthed with a scowl.

Arthur looked affronted. "Merlin, you can't just—"

Merlin cut him off quickly. "Um, just give me one second, Gaius… I think I left my… thing… in my bedroom…" He trailed off vaguely, and ran up the stairs to his room before Gaius could protest. He waited the few moments it took Arthur to catch on and follow him inside, then closed the door behind them.

"It's a mess in here, Merlin," was the first thing out of Arthur's mouth. He cast a disdainful look around at the clothes and books scattered about.

"Yeah, well, I'm usually too busy cleaning up after you to do anything about it," he snapped, his carefree facade slipping away as his irritation resurfaced. "Your chambers would be far worse than this if you didn't have me doing all the legwork—"

"Why aren't you telling Gaius that you can see me?" Arthur interrupted, rounding on him, and Merlin scowled, wondering if the prat had even bothered listening. "He knows you have magic—which, I might add, is something we are going to discuss later—so what are you trying to hide from him?"

"I'm not hiding anything."

"Merlin, you were lying to his face."

"Thanks for the reminder," Merlin replied crisply, before taking a deep breath; sarcasm was not going to help either of them. "Yes, I was. It's just—it's easier not to involve him."

Arthur gave him a disbelieving look. "And how do you figure that?"

"He…" Merlin struggled to put it into words. "He gets overprotective sometimes. And he's not very keen on me using my magic."

"Why not?"

"Why do you think?" Merlin said incredulously, looking at Arthur like he was stupid. "If anyone ever catches me, your father will throw me on a pyre and have me burnt to death. Or did you forget about that?"

He felt a guilty satisfaction when Arthur winced slightly. At least the arrogance and superiority had slipped from his face.

"So, obviously," he continued, "Gaius doesn't approve of me using my magic for… well, anything, really. Unless there are lives at stake, and science has completely failed us."

Arthur frowned. "So you're lying to him because he'll be angry with you?"

"What? No," Merlin said, "I mean, partially. Look, he hates getting involved in these things, so I usually try to keep him out of it. He won't be any help, he'll just lecture me and forbid me from using magic. He doesn't like breaking the law."

"Merlin," Arthur said slowly, "you do realize that we're talking about a man who is actively harboring a sorcerer, right?"

Merlin paused. "Well, yes, but—he still—"

"He breaks Camelot's most severe laws every single day."

"Yes, but that's different! He knows I can't help having magic, he just disapproves of me using it."

"And that's why you're not telling him."

"Yes! Wait—no—" Merlin was losing track of what he was trying to argue.

"What I'm still getting out of this," Arthur said, raising his eyebrows, "is that you lied to Gaius because you're scared of being yelled at."

Merlin could feel his ears burning. "Of course not—"

"You're worried that he'll tell you off for using magic to make that potion."

"I mean—it's more complicated than that, it's—he doesn't—" Merlin floundered for way to explain.

"This is pretty pathetic, even for you." Arthur's expression was stuck somewhere between irritation and amusement.

"Shut up, you prat," he said hotly.

"No, I won't, because you need to tell him."

Merlin glared at the floor. "You're insufferable."

"And you're being ridiculous!" Arthur snapped. "Have you forgotten that I've been enchanted? I'm stuck here as some sort of invisible ghost, and we don't know why or how. Gaius is the expert on these things, we need his help, yet you're keeping it from him because you're scared of a lecture!"

Merlin scowled. "I will tell him if it becomes necessary."

"Oh really? Because I think it's necessary right now."

"We haven't even tried to figure it out yet, we don't know if we need him—"

"Merlin, I'm ordering you to tell him immediately."

"You're not exactly in a position to be making orders, sire," he snapped before he could stop himself.

Arthur gave him a measured look, and Merlin cringed internally. That was too bold of a comment to say to any noble, and this wasn't just any noble, this was Arthur Pendragon he was sassing. Which was probably an extra terrible idea now that Arthur knew he had magic, and could still have him arrested as soon as he was back to normal. But what he'd said was technically true, and Merlin had never been one to back down from a bully; he kept his head up and his gaze level with Arthur's, daring him to argue.

"Fine," Arthur eventually conceded. "You're right."

Merlin was rather taken aback. "I am?"

"This is not the time for me to be ordering you around."

Merlin tried not to look too surprised. He wasn't sure if Arthur was referring to the fact that he could not physically force Merlin to do anything, or that it didn't seem appropriate given the situation; then again, he wasn't entirely sure which one he himself had been referring to in the first place.

"However," Arthur continued, "that doesn't change the fact that we need Gaius. He might already know how to fix this. And anyway, how are we supposed to solve this without him finding out? He's bound to grow suspicious even if you don't tell him."

Merlin sighed. "Fine, I'll tell him eventually. Just… not yet."

Arthur huffed, but it didn't seem like he was going to argue again. Sensing that the discussion was over, Merlin led the way out, making sure to let Arthur slip past him before closing the door.

Gaius looked up as Merlin came down the steps. "Merlin," he said, "is there someone in your room?"

Merlin looked startled. "No," he said quickly.

"I heard you talking."

"Can't I get a bit of privacy without an old man spying on me?"

"It's hardly spying when your voice carries through the door," Gaius replied coolly.

Merlin grumbled something under his breath.

"How is it, Merlin," Arthur muttered, "that you manage to start an argument every time you open your mouth?"

"I do not," Merlin retorted, before remembering that he wasn't supposed to talk to Arthur.

Gaius raised an eyebrow.

"Oh, don't look at me like that," Merlin told him after an awkward beat of silence, "we all talk to ourselves now and then. You, of all people, have no right to judge."

"What on earth does that mean?" Gaius asked.

"Don't act so innocent, old man. I've heard you jabbering away when you think nobody's around. You get wrapped up in your potions and medicine and science and suddenly you're going on and on about the properties of herbs and whether or not adding a little bit more of this liquid will make the potion a little bit cloudier or if maybe you should substitute some of that root instead of the other and you chatter away with absolutely nobody around to hear you, except for me, of course, which is how I know about it. It's almost sad, really."

Gaius looked rather affronted. He started to open his mouth, but Merlin cut him off before he could reply.

"Oh, don't bother. If you're just going to deny it and ridicule me for thinking out loud, then I might as well go and do my research somewhere else, where I can discuss matters with myself in private. Have a nice afternoon, you old hypocrite." Before the speechless physician could react, he grabbed a pile of books and stalked out of the room. Arthur followed a second later.

"You never cease to amaze me," the prince said, falling into step beside him.

"Thanks, I guess."

"Where exactly are we going, then?"

"Er… I don't actually know," Merlin admitted, shifting the stack of books in his arms uncomfortably. "Hopefully somewhere I can talk to you without other people noticing."

"How about the library?"

Merlin stopped walking and gave him a look. "Have you ever actually been to the library?"

"Of course." Arthur paused. "At least, I think so."

"Well, Geoffrey is very protective of his dusty old books. He likes to hover whenever I go in there. Plus, I don't think he trusts me after the whole Lancelot incident."

"What did that have to do with you?"

Merlin hesitated. Arthur had argued that Lancelot deserved a chance despite the laws—he probably wouldn't be too angry about Merlin's law-breaking. Probably.

"I, um… I may have been in the library earlier that day. Looking at the book of nobility."

"Merlin," Arthur said, pinching the bridge of his nose, "are you saying that you made the fake seal for Lancelot?"

"You said it yourself, he still deserved a chance to prove himself! And it wasn't his idea, if that's what you're thinking, I convinced him to lie about it."

Arthur sighed. "Fine, so the library isn't an option. Where else can we go?"

Merlin thought for a minute. "Well, your chambers—"

"No," Arthur said immediately.

Merlin gave him a strange look. "—are not an option, is what I was about to say. The king is in there constantly."

"Of course," Arthur agreed quickly.

They fell into an uncomfortable silence.

"We could go to the vaults," Merlin said with a hint of amusement.

"Don't be ridiculous. That's both pointless and impossible."

"It might be pointless," the servant conceded with a sly smile, "but it's absolutely possible."

Arthur stared at him for a moment. "Merlin," he finally said, "do I even want to know how many laws you break on an average day?"

"Oh, it depends on the day," Merlin said, grinning. Arthur groaned.

"Can we please just figure out where we're going before you tell me about all the other illegal things you've done?"

"Whatever you say, sire."

They fell silent again. Arthur's brow furrowed in thought.

"This is ridiculous," he said. "We have an entire castle to use. We just need somewhere private."

Merlin looked thoughtful for a moment, then perked up. "Actually, I know a place." He adjusted his grip on the books and started walking again, and Arthur followed with a sigh.

"I've never been here before," Arthur said a few minutes later when Merlin led him down a narrow passage.

"Servant's shortcut. Pretty useful for those of us with impatient masters. Most people don't know about them."

"Huh," was Arthur's only response.

"And… here we are. Just as I expected. Completely empty."

Merlin led the way into a nondescript room, dropping the books onto a dusty table which sat in the middle of the room with a thump. Arthur looked around, taking in the bare walls and sparse furniture. Besides the table and the few chairs next to it, the only addition to the room was a lonely tapestry on the wall and an old chest in the corner.

"What is this room?"

Merlin shot him a grin. "You know, considering you're going to own it one day, you don't know the castle very well."

Arthur scowled. "Just because I have more important things to do with my time—"

"Don't hurt yourself, I'm only joking. Few nobles ever have reason to come down here. Actually, nobody comes down here anymore. The servants try to avoid this route thanks to some rumors that it's haunted."

Arthur paused. "Haunted?"

Merlin shrugged. "Like I said, I think it's just rumors. I certainly haven't noticed anything strange down here. But people claim that weird things happen in this corridor, so nobody ever uses the room."

"What kind of weird things?"

Merlin looked directly at Arthur. "Oh, you know," he said, "strange noises follow people around down here… the furniture moves without anyone touching it… people hear whispering behind them when they're alone… that sort of thing."

Arthur thought he felt a sudden gust of cold air. He shivered involuntarily.

"I mean," Merlin continued, "that's just what people say. But nobody will come down here anymore, not since…" he shook his head sadly and lowered his voice. "Not since that poor girl died in this very room."

Arthur stilled. "A girl died?"

"They say the bloodstain never came out."

Arthur's eyes flickered around the floor of the room, automatically searching for a dark stain, until Merlin snickered. His gaze shot back to the servant,who was clearly trying not to smirk.

"You—you made all of that up, didn't you?"

"You were nervous," he countered.

Arthur glared at Merlin. "Of course not. It takes more than a ghost story to scare me. And anyway, I don't believe in ghosts." As soon as he said it, however, he was reminded of just last night, when he had wondered if perhaps he was a ghost. Merlin didn't need to know about that; he was already enjoying his little trick far too much.

"Alright, so nobody died," Merlin conceded, "but there are actually rumors. I'm sure there's a simple explanation, but the servants of Camelot are a skittish lot and they tend to avoid this corridor as a result. So we should get some privacy here at least."

"Great," Arthur said sourly. "Now are you going to read those books or not?"

"Sounds like someone hasn't had their breakfast," Merlin said cheekily, before getting a curious look on his face. "Actually, have you eaten anything since you woke up like this?"

The thought hadn't even occurred to him. He frowned. "I—I don't think I can. I mean, I'm not hungry or anything, but even if I was… it's hard to eat when you can't, you know, pick things up."

"You can't pick anything up?"

Arthur shook his head. "I can touch things, but I can't move them."

A thoughtful look grew on Merlin's face. "Hmm. Hold out your hand."

"You can't just give me orders like that, Merlin—"

"Oh, just do it."

Arthur was silent for a second, before sighing and stretching his arm out, his palm facing up. Merlin poked the prince's hand.

It moved when Merlin pushed it.

"I felt that," Arthur said, then felt very stupid. Merlin, however, just looked puzzled.

"I didn't."

"What do you mean?"

"I mean—your hand moved when I pushed it, but I didn't feel anything. It's like your hand wasn't even there. Hang on—"

This time, Merlin tried to grab his hand. A strange, painful sensation shot through it just as Merlin's hand touched his, and he jerked it backwards.

"What the hell was that?" Arthur asked.

"What happened?"

"It—I don't know, but it felt odd."

"In what way?"

Arthur thought for a moment. "...I can't describe it, it was too quick."

"Hold it out again," Merlin instructed.

Once again, Arthur hesitated before reaching his arm out, but this time because he was nervous. The sensation hadn't exactly been pleasant.

"This time," Merlin told him, "I want you to keep your hand still. Don't let it move from where it is right now."

Arthur silently complied. Merlin reached his own hand towards Arthur's, slowly this time. As soon as Merlin tried to grip his hand, a flash of pain ran up Arthur's arm again. He tried to hold still, but he couldn't help flinching. And just like that, Merlin's hand slipped past his own. He could see that it was on the other side, but he didn't remember feeling it touch him — he only remembered the strange pain.

"What just happened?" He asked.

Merlin frowned and drew his arm back. "I think my hand passed through yours."

Arthur looked down at his hand. It still looked as normal—and solid—as ever. "Are you sure?"

"It definitely looked like it. We can try again if you like—"

"I'll take your word for it." A chill passed up his spine. "What does this mean? Am I... not real?"

"Not necessarily," Merlin said, sitting down at the table and pulling a book towards him. "I think you're real, but maybe not in the sense that you're thinking."

Arthur huffed. "Care to explain what that actually means, instead of speaking in riddles?"

Merlin looked up and blinked. "Dear lord," he said, "that old lizard is rubbing off on me." Arthur couldn't quite tell if the comment was meant for him, nor did he know what to make of it, so he didn't respond. After a moment, Merlin shook his head slightly and cleared his throat. "Well," he began, "clearly, you do exist. How else could I be talking to you? So there's some part of you that is definitely here. But I don't think it's all of you."

Arthur felt a familiar unease rise in him. "You mean… the man in my bed. It's me, isn't it? I was right?"

"I think so. And I think I've known it for a while. I knew something was wrong when I was by your bed. It felt like something was missing, and… well, I think it was you."

Arthur quietly absorbed this information, turning the concept over in his mind.

"Then what exactly am I?" He finally asked. "A ghost?"

Merlin quirked his mouth to the side. "That, sire, is what we're here to find out. Why do you think I brought all these books with me?"

Arthur raised an eyebrow. "You really think you can find the answer in one of those?"

"Something usually turns up," Merlin said, opening the book in front of him. "And you're in luck—I think I recall seeing something like this before, I just have to figure out where it was."

"Great," Arthur said. "And how long is this going to take?"

"Who knows?" Merlin responded, already leafing through the pages of the first book. Arthur watched him for a few moments, then looked at the stack of books. There were at least five or six more, and some of them were fairly thick. He stood there awkwardly, watching Merlin read.

"I'll just… sit here, then."

"Mmh." Merlin barely seemed to hear him, busy staring at a page covered in some language that Arthur didn't recognize.

He sighed and sat down on one of the dusty chairs, praying it wouldn't take too long.

A/N: I mentioned at the top that I might be going back to adjust some things. I'll only adjust minor things, but I think it will help. And I know this chapter is a little slow, but the story is about to get a lot more interesting.

I know I'm pretty unreliable when it comes to updating. I never mean to go so long without updating; life gets in the way, and I run into problems with the story, and before I know it months have gone by. I really did plan this entire fic out before I even started writing it, but I like to post each chapter as I write it rather than publishing after I've finished, because I value the input I get from my readers. I like to hear the feedback from you guys and incorporate it as I go. So yes, I often take a long time to update, and I want to sincerely thank all of you who haven't abandoned me yet. I regret that I'm not a quick or efficient writer, and that I get stuck/distracted for long periods of time, but it means the world that some of you have stayed anyway. I swear I'm not giving up on this.

As usual, please leave any feedback you have, good or bad. And even if I don't respond, I can assure you that I am reading every single review/message and taking them all very seriously. Thanks again for everything, guys. You're the reason I keep writing.