This is a fic I've wanted to write for ages, so I'm glad I managed it eventually! This is set back in the second series, shortly after 'The Once and Future Queen'. There's a bit of Arthur/Gwen and a hint of Merlin/Arthur, but it's not really a pairingfic. I hope you enjoy it!

The Once and Future Queen (and Present Manservant)

It creeps up on him gradually as he wakes, the slow awareness that something's wrong. For a while, Merlin thinks it's just the last clinging shreds of a bad dream, but as his mind clears he becomes conscious that, no, something has definitely changed.

He frowns. He can't work out what—

It's gone, he realises, and he sits bolt upright in the bed. His magic is gone, and he doesn't have to hide any more, he doesn't have to lie any more, but – but magic is all he has, and Arthur can barely keep himself alive one day to the next without Merlin muttering some incantation behind his back, how's he supposed to...

He is so busy panicking that it takes him several seconds to register that this isn't his bed.

Also, he has breasts.

Merlin has experienced many things since he came to Camelot. He has spoken to a dragon, encountered a unicorn and, on one memorable occasion, spent an entire afternoon chasing after a bucket he'd accidentally brought to life.

Turning into Gwen is definitely new.

How did this happen? Did he do this himself somehow, accidentally? Is it the doing of some enemy of Camelot? He's not sure what any enemy of Camelot might be trying to achieve by turning the prince's manservant into a maidservant, though. Maybe someone knows about his magic and did this to cut him off from it? On the other hand, maybe someone's just trying to bring down the kingdom by making sure Arthur doesn't have anyone to help him get dressed in the mornings.

More importantly, is the real Gwen all right? Is she in this body with him somehow? Is she running around looking like him?

He checks under the bedcovers, just to make absolutely sure there isn't a second Gwen in here he somehow didn't notice.

Better go looking for her.

"Guinevere?"

Merlin keeps walking. He's decided to visit Gaius first; if anyone in Camelot can tell him what's going on—

"Guinevere," Arthur repeats, and Merlin realises with a start who he means.

"Oh! Er, sorry, I was... walking."

"Yes," Arthur says, after a tiny pause, "I can see that."

"To see Gaius," Merlin inexplicably feels the need to add.

"Are you unwell?" Arthur asks, with a hint of concern that, Merlin thinks bitterly, would not be there if he knew who he was really speaking to.

"I'm fine," Merlin says.

Arthur looks relieved. "Good. Will you walk with me, in that case? I'm sure Gaius can wait."

Merlin realises that he's an idiot. Probably too late to say that actually he's deathly ill and needs to see Gaius right now.

Still, Arthur normally shows Gwen a bit of respect. Maybe it'll be nice to spend time with him like this. Merlin just needs to be really, really careful.

"Have you seen Merlin today?" Merlin asks, as they climb the stairs side-by-side. Gwen's clothes are making him really uncomfortable; whenever his legs brush against each other, he thinks for a horrible moment he's forgotten his trousers again before remembering he's wearing a dress.

"I think Merlin's been at the cider," Arthur confides. "He came into my chambers this morning claiming to be you."

Okay. He's still got no idea what happened or how to undo it, but at least he knows Gwen's somewhere.

"Really?" Merlin asks. "That's very interesting. And, er, where would he be now? My lord," he adds, hastily. For a moment he's afraid his awkwardness will give him away, before realising that, in Gwen's body, it probably makes him more convincing.

"No idea," Arthur says. "Not doing his job, that's for certain. Probably sleeping it off." They've arrived in the corridor outside Arthur's chambers; he waves a hand, indicating the door. "Anyway, as my manservant isn't around for once, would you like to join me? There's something I'd like to discuss with you."

What could Arthur possibly need to discuss privately with Gwen? Does Arthur secretly ask for the other castle servants' opinions on political matters when Merlin is out of the way? Merlin's going to be so annoyed if that turns out to be it. He bows, realising too late that he should probably be curtseying, and follows Arthur into the room.

Well, this isn't what he expected.

Arthur is kissing Gwen. Arthur is kissing Gwen. The crown prince is kissing a servant, and it doesn't seem like it's the first time he's done it, and Uther is going to kill someone when he finds out. Uther is going to kill everyone when he finds out.

Merlin is so astonished by the revelation (Arthur! And Gwen! Arthur and Gwen!) that it takes him a moment to realise Arthur is kissing him, too, and that's when things get even weirder. There's not much that's weirder than waking up in the body of someone you really wouldn't expect your friend and master to be kissing and then being kissed by him anyway, but – but Arthur's hands are on his (Gwen's) shoulders and Arthur's lips are warm against his (Gwen's) own, and maybe, maybe Merlin doesn't completely mind.

Well, he minds a bit, but that's mostly because Arthur is so gentle with Gwen and Merlin just gets things thrown at his head when he's in his own body. How is that fair?

He is so overwhelmed by surprise and confusion that he's not really thinking when Arthur pulls back. "You and Gwen?" he blurts out.

Arthur frowns, understandably perplexed. "What?"

"I mean," Merlin says, mentally scrabbling for something to say, "I mean sometimes I – I still can't believe we're – I mean, I'm a servant."

Arthur smiles. "And that makes no difference to me. We've been through this."

Oh, Arthur is definitely going to have to treat Merlin better when this switching-bodies thing is sorted out. This isn't fair at all.

"Anyway," Merlin says, "er, I – I should..." He should leave, that's what he should do, it's not fair to Gwen or Arthur if he stays here, but if Gwen is happy with all this he doesn't want to make things difficult for her by making it look like she's running away. Merlin casts desperately around Arthur's bedchamber, trying very hard not to look at the actual bed, and spots a pair of soiled boots. He lunges for them and bobs up again, boots in one hand. "I should – I'll just go and polish these."

Arthur laughs and lays his fingertips along Merlin's cheek. His smile is warm. Merlin feels like a hind in the sights of a crossbow. "That's not your job, Guinevere. I'm sure they can wait until Merlin recovers."

Merlin laughs nervously, backing away. "I just... really like polishing boots. I'll – good day, my lord." He tries to curtsey, even though he has no idea how, and then turns and flat-out bolts out of the room. So much for not looking like he's running away. He drops one of the boots and very nearly trips over it in his haste, but he manages to catch himself just before he hits the floor and keeps running, Arthur's concerned shout of "Guinevere?" echoing down the corridor after him.

Leaving one of the boots just outside Arthur's room probably isn't going to do anything for his 'polishing' story, but there's no way Merlin's ever going back for it.

Merlin leans against a wall and closes his eyes and wraps his arms around himself and tries not to think too hard about what just happened. He's out of there. He did the right thing, even if he didn't do it quite as smoothly as he could have. It's fine.

Actually, after the initial shock on several levels wears off, it turns out to be remarkably easy not to think about. He has a much more pressing question on his mind right now.

Merlin has never really thought of his magic as something he can feel, before, but then again he's never known anything different. This morning, he woke up and knew, as certainly as he would know if he woke to find someone had taken his eyes out during the night, that it was gone.

And, if he could feel it was gone, does that mean Gwen will be able to feel it's there? He doesn't think Gwen will betray him, but there's a reason he's never told her about his powers.

He needs to find her. He needs to find her now.

"Gwen," Gaius says, smiling. "How can I help you?"

"I need to find Merlin," Merlin says, breathing hard from the exertion of running. Running is so strange in this body; his weight is all distributed differently and he feels constantly on the verge of overbalancing. He fell over more than once on his way here. Gwen's knees are scraped and her elbows are bruised; he hopes she'll forgive him if they can switch back. "Have you seen him?"

Gaius' smile fades a little. "Is everything all right?"

"Oh, yeah, fine," Merlin says, and then, after a moment, "Not fine. I think I might need some help."

"I'd be happy to offer whatever assistance I can."

Merlin hesitates, but... it's Gaius. They've never had any secrets. "Do you know of any magic that can transfer a person's mind to someone else's body?"

For a moment, Gaius just looks at Merlin. "I don't know what gave you the idea that I would know about such things," he says eventually, carefully.

"Gaius," Merlin says. "I'm Merlin."

Gaius' eyes widen very slightly. He regards Merlin for a moment longer, and then he looks away. It takes Merlin a moment to realise why.

"Are you laughing?" Merlin demands.

"I wouldn't dream of it," Gaius says, turning back. He almost manages to keep his voice steady, too. "Mind transference, you say?"

Apparently the incantation for 'switching one's soul with the being last touched' mainly consists of loud snoring noises, which explains a lot. Magic is ridiculous sometimes. It's a good thing he hugged Gwen goodnight after giving his horse a pat, really.

They find a spell to reverse it, but Merlin can't do it. He just can't. He tries about thirty times, but he's not used to performing magic from scratch; he's always had his natural ability to support him. Gaius can't help; the spell must be performed by one of the victims of the switch, and in any case Merlin doesn't want to ask Gaius to do magic for him. He's put Gaius in enough danger already.

So there's only one option.

"I need to find Gwen," Merlin says. "If I've lost my magic, maybe she has it."

What if she doesn't, though? He's been hoping that she doesn't – he needs to avoid letting anyone find out he's a sorcerer, after all – but if his magic didn't stay with her they might never get out of this situation. Maybe he'll have to spend the rest of his life as Morgana's maidservant. Actually, that might not be so bad; Gwen certainly seems to get fewer things chucked at her than he does.

Still, he doesn't think he'll be disappointed if she can change them back.

He'll need to find her first, of course. Where is she?

Merlin knocks on the door of Morgana's chambers.

"Have you seen Gwen?" he asks, breathlessly, when Morgana opens it.

Morgana looks extremely perplexed.

"Oh," Merlin says. "Right. I'm Gwen. Sorry, I... forgot." There was probably a better way to recover from that, but it's too late to worry about it now. "Have you seen Merlin?"

"He dropped in a moment ago," Morgana says. "He asked where you were. I said I hadn't seen you, so he said he'd ask Arthur." She hesitates. "He was acting strangely as well. I think Arthur and I might both have been working our servants too hard."

He finds her in Arthur's chambers, a few seconds too late.

The boot Merlin left behind hangs in the air, frozen in mid-flight. Arthur is clinging to one of his bedposts, staring at Gwen.

Her eyes – her borrowed eyes, Merlin's eyes – are gold.

"Oh," Merlin manages as the boot drops to the floor, and oh, help, they're all going to die.

"I'm so sorry, Merlin," Gwen gabbles, "I'm so sorry, I didn't know, I mean I noticed before but I didn't know how to control it and obviously I tried and I would never have – I'd never – why didn't you tell me—"

"Merlin," Arthur says, and Merlin can hear a thousand things in the way he says his name, none of them good.

"I'm sorry," Merlin says, miserably.

"You knew about this?" Arthur demands, shifting his stare to Merlin, but only for a moment; his eyes snap back to Gwen almost immediately.

Merlin is tempted to say that no, he had no idea, are those magical powers he has, really?, but then he realises that, as he is still in Gwen's body, that probably isn't what Arthur meant. "Look, Gwen has nothing to do with this. She didn't know anything."

"Guinevere," Arthur says, "this is quite a stressful moment for me. I've just discovered my manservant is a sorcerer, so if you could say something that makes half an ounce of sense—"

"I'm not Gwen," Merlin says.

"Oh, for goodness' sake," Arthur says, rolling his eyes and focusing on Gwen again. "Merlin. Explain yourself."

"She's not Merlin," Merlin cuts in, quickly. "I'm Merlin. You can't execute her, because then you'd be executing Gwen and she didn't do anything and please just wait, I swear we can change back, just wait until then and you can tell the king."

"You can't!" Gwen exclaims. "Arthur, I know Merlin. You know Merlin. You know he would never try to hurt you."

"Will someone please," Arthur growls, "tell me what is going on?"

"All right," Arthur says, breathing deeply. "Let me make sure I'm clear on this before we go on to establish who exactly has been concealing dangerous secrets from me. You" – he points at Gwen in Merlin's body – "are Guinevere. And you" – he points at Merlin in Gwen's – "are Merlin."

Gwen nods.

"I think maybe we should just talk some more about that," Merlin says, with forced casualness. "I mean, it's a lot to take in in one day. Maybe we could discuss the magic thing tomorrow, or in a year or something."

Gradually, Arthur's expression takes on an altogether different but no less appalled quality.

"I kissed you," he says.

"Oh, no, really?" Gwen asks, pressing her hands to her mouth. Well, his hands to his mouth, really. Merlin doesn't know what she's so worried about; in terms of secrets getting out, he's pretty sure he's still losing.

"Yes," Merlin says, because there's no way he can really deny it. This is going to be extremely awkward, but at least it's a distraction from the magic aspect. "You did."

There is a pause.

"Nobody can know about this," Arthur says.

Merlin blinks. "Which, er, which part?"

"All of it," Arthur says. "Any of it. They cannot know of my relationship with Guinevere, particularly as I've just discovered she's a sorceress, and they certainly can't know I kissed my manservant."

"Gwen isn't a sorceress," Merlin says instantly.

"I'm not," Gwen says. "I swear I'm not."

"Really," Arthur says flatly, turning to Gwen. "Explain to me, then, how you can use magic."

Gwen hesitates.

"I would love to believe you," Arthur says, "but you understand that the situation makes it difficult."

"I... I don't understand it myself," Gwen says. "I promise you that I've never used magic before today. Since I woke up as Merlin, strange things have been happening. I can't stop them."

"It's because we were switched over," Merlin explains to Arthur. "After the change, she couldn't control the magic, so..."

"So she is a sorceress, then."

"No," Merlin says, heavily. "It's me. When we were switched, the magic stayed in my body."

For a moment, Arthur is silent.

"That makes no sense," he says, slowly. "Magic must be learned. If what you are telling me is true – if you're Merlin, and you are somehow a sorcerer – that doesn't explain how Guinevere would know the incantations to use. What difference does being in your body make?"

"I didn't use an incantation," Gwen says. "You threw the boot, I saw it coming towards me – it just happened."

"That's impossible."

"Do you really think I would deliberately perform a spell in front of your eyes?" Gwen asks, desperately. "Merlin must have been born with this, or – or something; he hasn't been learning magic to harm the kingdom."

"It's true," Merlin says. "I've always been able to use magic."

Arthur stares at Merlin. Well, actually, he stares at Gwen in Merlin's body first and then shifts his stare to Merlin in Gwen's. He seems a bit confused about where he's meant to be staring, really, but the impact gets across. "Always," he says. "Even when we first met. You've always been a sorcerer."

Merlin shrugs. "Surprise," he says, weakly.

"You were a practitioner of powerful, dangerous arts," Arthur says. "You." He pauses. "And yet you still never did anything useful to combat all the danger we found ourselves facing?"

This is so wrong and so insulting that for a moment Merlin forgets to worry about his impending execution and just gapes.

"If I hadn't been around, you'd have been killed about seventeen times!" he exclaims.

"Oh, come on, Merlin, don't—"

"That feast," Merlin says. "Just after I came to Camelot. Your father made me your manservant because I saved your life."

"Yes, which gave him an obviously exaggerated impression of your usefulne— are you telling me you used magic to do that?"

Perhaps Merlin is going to die, but he's going to die with full credit for his actions, thank you very much. "All those times branches fell on people you were fighting? All those times you got knocked out and when you woke up whatever attacked you was gone? I know me being around might have given you the wrong idea, but being unconscious isn't actually much of a battle strategy."

"You see," Gwen says, putting her borrowed hands on Arthur's arm (there's a very slight hint of laughter in her tone, which Merlin hopes Arthur doesn't pick up on), "he only ever tried to help you. I knew he wouldn't hurt you, even if he is a sorcerer. Maybe magic doesn't have to be a bad thing."

Arthur looks down at her hands in evident unease. "Look, Guinevere, I appreciate the gesture, but are you sure you won't... accidentally incinerate me, if you're touching me? I mean, if you really can't control this magic..."

"It's not random," Merlin puts in. "It's instinct. Nothing's just going to happen out of nowhere. She's not going to incinerate you unless you really make her want to."

"Well," Gwen says, managing a smile, "I suppose you'll have to try not to anger me, my lord."

"Not executing me would probably help with that," Merlin says. It doesn't come out sounding as light as he was hoping it would. "Just saying."

Arthur frowns at him.

"Please," Merlin says, Gwen's voice almost breaking on the word. Definitely not managing to make this sound light. He's on the verge of tears, he can feel them in Gwen's eyes and her throat, and he tries to blink them back. "I – I'll leave Camelot, if you want."

What will he do if he's banished? What will Arthur do? Arthur needs him, even if he doesn't realise it.

(What will he do if he's executed? Not a lot, probably.)

"Oh, Merlin," Gwen whispers.

Merlin stares at Arthur's hands; he can't meet his eyes. The silence is horrible. Maybe he'll be given time to talk to his mother, at least.

"You've been in the perfect position to kill me for a long time," Arthur says, after a long moment. "If you haven't yet succeeded, either you don't intend to harm me or you're even more incompetent than I give you credit for. If it's true that you were born with magic... if you didn't choose to learn it as a weapon against the kingdom..."

Gwen tightens her hands on his arm.

"You've really... I don't intend to say I wouldn't have defeated our enemies without you," Arthur says. "But – this magic of yours. You've really been using it for my protection?"

"Almost nothing but," Merlin says, quickly. "Well. And polishing your armour. And cleaning your boots."

Arthur's frown deepens. "All this time? I evidently haven't been giving you nearly enough work."

Merlin hadn't thought about that aspect of his magic being discovered. Maybe he should just let himself be executed.

There is a very long pause.

"Well," Arthur says, eventually, "I have important royal duties to perform; I don't exactly have the time to find a new manservant, do I?"

Merlin almost laughs in relief. "You're only saying that because I look like Gwen."

"Oh, absolutely. The moment you switch back, it's off to the axeman with you. But for now I suppose you can stay."

"Thank you, Arthur," Gwen says, smiling broadly. "I knew you would make the right decision." She plants a little kiss on his forehead. It's very strange to watch.

Arthur looks at her-as-Merlin's hands, still on his arm, and then he looks up at her-as-Merlin's face, and he smiles a strange, fond smile that is quickly cut off.

"I can't tell you how disturbing this is," he says, after a moment.

"So this is the incantation?" Gwen asks, looking at the book laid open on Gaius' table. She casts a slightly nervous look in Arthur's direction. Merlin can't blame her; the idea of using magic openly in front of the crown prince of Camelot is making him feel very weird, and he's not even the one doing it.

"Indeed," Gaius says. "It should restore both of you to your true bodies. Merlin will show you how it is pronounced; you can follow his lead."

"I can't believe you knew," Arthur mutters, staring at Gaius. Everyone present ignores him; it's at least the fourth time he's said it.

"Merlin's natural aptitude for magic should help you," Gaius says, "but as you have no experience yourself you must understand that it may take several attempts."

Gwen nods. "I'll try as many times as it takes."

"How did these books go unnoticed?" Arthur murmurs.

Two hours. Gwen has been repeating this incantation for two hours with no effect. Gaius has gone to bed. Arthur has left; someone's bound to come looking if the prince is missing for too long. Merlin has no idea why anyone ever bothers to learn magic.

"I'm so sorry, Merlin," Gwen whispers. "I don't understand why it's not working."

"It's fine," Merlin mumbles, not opening his eyes. He's half-dozing, arms folded on the table to cushion his – well, Gwen's – head, listening to Gwen as she paces and mutters. "Took me a while when I started with incantations, and I'd had all my life to get used to having magic. We could try again tomorr—"

He realises his voice has changed before he realises he's suddenly standing up, although not for long because the floor seems extremely eager to introduce itself. He yelps and throws out his hands and power rushes through him and a cushion of air billows up to slow his fall, which is good because he didn't really fancy breaking every bone in his arms.

His arms. Not Gwen's. His.

"Oh," Gwen's voice says, sounding startled. "I suppose it worked." There's a pause, and then her head appears over the edge of Gaius' table, looking down at him. "Are you all right?"

"Fine," Merlin croaks, because getting out a phrase like 'incredibly winded' seems far too ambitious right now.

"MERLIN!"

Two months later, an irate voice echoes down the corridors. There are footsteps audibly getting closer very, very fast. Merlin leaps out of bed seconds before Arthur bursts into his room.

Well. Not his room, technically.

"Undo this immediately," Arthur snarls. "I look ridiculous."

"Really? I think you look very handsome."

"I'm going to murder you, Merlin."

"That's definitely treason."

Arthur lunges at him. Merlin dodges and runs.