DISCLAIMER: Don't own it!

This is set in late season 4.

CHAPTER ONE

Twenty-four hours after Morgana cast her latest spell to bring about Arthur's downfall, the knights began to notice the effects of said spell.

"Arthur hit Merlin."

Silence followed these three words, which had been uttered by Sir Elyan with an almost comical air of disbelief. Percival paused, his sword in mid-swing, and Gwaine tottered slightly, off-balance as he braced himself to parry a blow that never arrived. Leon spun around so quickly that his own hair nearly gave him whiplash.

On the other side of the training field King Arthur was slowly lowering his fist to his side. Sprawled on the ground in front of him was Merlin, looking like a deer who'd been startled by torchlight. His eyes were wide with shock, his mouth hanging open as he raised a hand to gingerly prod at his reddening cheek.

After an awkward moment in which everyone stood frozen, Arthur turned, back stiff and straight, and strode off towards the armoury.

"Arthur-" Gwaine broke off as Leon grabbed him and pushed him back.

"Gwaine, leave it," the older knight ordered.

"Leave it?" Gwaine tossed his hair back, eyes flashing with outrage. "Leave it?"

"Now is not the time," Leon said shortly. He let go of Gwaine and the four knights moved over to Merlin, Percival pulling him swiftly to his feet and steadying him.

"Um, thanks," Merlin said, still looking a bit startled.

"You alright?" Gwaine asked, brow still furrowed in anger. He grasped Merlin by the shoulder as though this would somehow undo his injury.

Merlin rubbed the side of his face, which was already starting to bruise. "Fine."

"What happened?" Elyan spoke up, glancing in the direction Arthur had vanished. "That wasn't like him..."

Understatement of the century, Leon thought, because in all the time he'd known Arthur, he'd never once seen him strike Merlin – not deliberately, not like that. Manhandle him, sure, yell at him, yes, but 99 percent of the time it was all in jest.

"I don't know." Merlin seemed to have shaken off his state of shock now, his gaze hardening for a brief moment before he forced a grin. "I brought up Gwen... probably shouldn't have. He's been in a bad mood ever since he got out the wrong side of the bed this morning."

Gwaine was still frowning, still had a hand on Merlin's shoulder. "That's no call for him to hit you!"

"It's fine, Gwaine." Starting to sound slightly exasperated, Merlin pulled away and gathered up Arthur's sword and shield, which were lying on the ground nearby.

Leon had never known Merlin to sound so annoyed, but he supposed if he'd just been walloped by his best friend he'd be rather put out as well. The fact that Arthur had just left his gear lying about was also oddly out of character for the king. He filed these thoughts away at the back of his mind as he watched Merlin wave off Percival and Elyan's concern with a slightly strained laugh and follow in the same direction as Arthur.

"Something's wrong here."

Elyan was the first to say it, but from the looks on his fellow knights' faces Leon could tell they'd all been thinking it.

Gwaine clucked his tongue thoughtfully. "Aye, you got that right."

...

...

...

It all began, as most of the strange happenings in Camelot did, with Morgana, who had noticed that Agravaine had an alarming tendency to burst into her hovel without warning. If it hadn't been for the magic 'triggers' she'd set up around the area to warn her when someone approached, he may well have encountered the sight of her bathing.

As it was, she magicked away the tub and quickly pulled on a robe just as he marched in as though he owned the place.

"Ever heard of knocking?" she snapped, irritated at having been interrupted during a rare moment of downtime.

"Apologies," he replied, inclining his head and eying her wet hair curiously. "I've brought you supplies," he added, passing over a sack, which she supposed made up for his intrusion.

Morgana dug through the sack and pulled a face. "Do you people eat nothing but chicken, sausages and grapes?" she muttered, before pulling out a handful of fruits and setting the food aside. "What news have you for me?"

Agravaine made himself at home, sprawling down in a chair and narrowly avoiding knocking over a stack of vials that would have turned him into a rather unpleasant amphibian.

"Arthur," he said with distaste, "Is progressing unfortunately well. Trade with Camelot's allies is blossoming. He's settled into his role as king well. He's even managed to reduce poverty in the outer villages. Tomorrow he announces the new fiscal policy and he intends to take away some of the taxes that Uther imposed."

Morgana's face twisted into a scowl. "You told me he had found Guinevere's ring in the forest," she murmured. At least that was one problem out of the way – as far as she knew, Gwen was dead, killed on a hunt while in the form of a deer. "Did that not have any effect on him?"

"Apparently not." Agravaine leaned back in his chair and raised his eyebrows at her, obviously waiting for her to come up with a new plan.

They sat in silence for a while, Morgana gazing into the fire, lost in thought. After some time a slow smile spread across her face and Agravaine stirred, looking over at her expectantly.

"Why should I take down Arthur," Morgana began slowly, "When I could let him take down himself?"

"I don't understand," Agravaine said immediately.

Morgana turned to him, grinning now, her eyes gleaming with delight as the plan took shape in her mind. "What if the people saw me as a better choice for Queen? What if they no longer wanted Arthur on the throne?"

"That would be marvellous, but it would never happen," Agravaine replied. At Morgana's filthy look, he shrugged. "Well, Morgana, when last you were on the throne you burned their crops and executed any who stood against you."

She huffed. "But say Arthur became cruel. Say he became as bad as Uther was – nay, worse. Oppressive, selfish, raising taxes through the roof and working his people to death. Say he turned against his own friends, those faithful knights of his and that despicable Merlin." This last name was said with a distaste she usually reserved for comments about her late father.

Agravaine still looked blank. "Arthur would never do that."

"Not of his own volition, he wouldn't," Morgana smirked, and wiggled her fingers in the air. Agravaine finally caught on.

"An enchantment."

"Bravo," Morgana uttered, rolling her eyes. "Exactly. A spell that would take over his mind, twist his thoughts and actions, chill his blood and harden his heart until he becomes nothing more than a tyrant."

Agravine smiled. "While I remain the voice of reason, fruitlessly trying to save the kingdom until finally the people welcome Arthur's downfall and you assume the throne, now the lesser of two evils."

"Exactly!" Morgana strode over to the shelf on which she kept various brews and potions. Agravaine watched in fascination as she mixed bottles of strange-smelling substances, added a drop of venom from the fangs of a small serpent-like creature coiled in a basket atop a cupboard, and finally uttered words in the Old Tongue over the concoction, her eyes flashing briefly gold before a plume of steam rose from the beaker.

"Is that it?" Agravaine asked, aghast that such a potion could be created so simply.

Morgana arched her brows at him and poured it into a small glass bottle, pressing it into his hand. "That's it. Slip it into his food and it should begin to take effect after he has slept."

"Excellent." He tucked it into a pouch at his belt and made for the door, grinning over his shoulder at her. "I'll keep you informed."

"Don't fail me, Agravaine," she said as always, before settling by the fire again, her lips stretching into a blissful smile.

"Camelot won't know what's hit her."

Agravaine was pleasantly surprised when fate gave him the perfect opportunity to put Morgana's plan into action that very night. It was Gaius' birthday, and it seemed that the physician had planned to keep the event quiet – and indeed, might have, if a certain manservant hadn't blabbed about it to a certain alcoholic knight, who had then, of course, organised a raucous celebration in the city's largest tavern.

Agravaine wasn't sure why he had been invited – probably out of politeness, as Leon had been the one arranging the guest list. As it was, he stood in the corner sipping a mug of mead and smiling simperingly around as though he wasn't the one responsible for Gaius' kidnapping some months ago.

I suppose there is reason to celebrate, he thought mockingly as he headed over towards Arthur, after all, one year older which means one less year until the old codger kicks the bucket.

The king was sitting between Gaius and Merlin and seemed to be having entirely too much fun, laughing over some story Gwaine was telling.

Gwaine, Agravaine thought, wrinkling his nose. Arthur's favourite knights were rowdy peasants, the lot of them, and Gwaine was the worst of the bunch.

"Your highness," he interrupted, coming up to Arthur, "More drinks?"

"Don't worry, Merlin can get them," was Arthur's response, giving his servant a grin and a shove. Merlin rolled his eyes and started to get up, but Agravaine pushed him back onto the bench.

"Really Arthur, give the poor boy a break for once," he chuckled, taking up the tray of mugs. Arthur spluttered and the knights at the table roared in agreement and Merlin shot Agravaine a startled look before ducking his head and laughing.

Too easy, Agravaine thought as he moved to the counter where the bartender, obviously overjoyed at the amount of business he was getting tonight, happily refilled the drinks. Agravaine discreetly slipped the potion into Arthur's pitcher and returned to the table. There was a horrible moment where he thought he'd gotten the cups mixed up and given the potion to Percival instead, but he relaxed as he realised that no, everything had gone to plan.

He retreated to the side of the room and nursed his own drink. To anyone watching it seemed as though his grin was the result of good wine and pleasant company. Just a loyal servant of the king's enjoying the celebration.

Now it's just a matter of time. Watch out, Arthur...

If the way Arthur squinted and groaned when Merlin flung open the curtains was anything to go by, it seemed he had had a little too much to drink last night.

"Rise and shine!" Merlin exclaimed brightly, moving over to the bed and stripping Arthur's covers back. The king let out a shout of complaint, swatting at Merlin as he scrabbled for the covers. There was a bite in the air this morning and as usual he'd decided to sleep shirtless.

"Hungover, Arthur?" Merlin laughed as he clattered around with the fire poker. "Gwaine'll have a laugh at that – and after all your claims you could hold your drink better than him-"

"Would you just stop talking for once!" Arthur snapped, but not in his usual jovial tone.

Merlin stared at him over his shoulder and Arthur himself blinked, seeming startled by the vehemence in his own tone. After an awkward pause Arthur scrubbed at his eyes irritably.

"I have a splitting headache. Keep the noise down, would you?" he muttered, and Merlin smiled sympathetically and nodded.

"I'll see if Gaius has something to fix it."

"Thanks," Arthur mumbled, rolling out of bed. Merlin moved forward to dress him, thoughts whirling. A letter had arrived from his mother this morning. Apart from the usual news about what was happening at the village and inquiries about his health, she'd told him that Gwen was staying in Ealdor. Merlin was relieved to hear it, now reassured that she hadn't been captured or killed, but was torn about whether or not to tell Arthur. He supposed he should, considering if their roles were reversed he'd want to at least know she was safe, but at the same time bringing up mention of the woman always resulted in Arthur threatening him with banishment.

"Careful!" Arthur barked as Merlin fumbled with the laces of his shirt.

"Someone's grumpy," Merlin muttered, tying the last knot and stepping back.

Arthur rubbed his temples and squinted about the room. He seemed to be steadily descending into anger, marching over to his desk and flipping violently through the stacks of papers.

"For heaven's sake, Merlin, where's my breakfast? I have a council meeting an hour and I don't want to discuss economics on an empty stomach!"

"I'm getting it, I'm getting it," Merlin said, making a tactful retreat. Arthur's tone held no trace of its usual amusement – he seemed genuinely annoyed, and Merlin wondered if perhaps the stress of being King was starting to get to him.

The rest of the day didn't go any better. From what Merlin heard from passing servants, Arthur had been irritable in the court session, refusing to listen to the advice of his counsellors and Agravaine, turning away a peasant who attempted to come to him regarding some sort of potato disease affecting the crops, and going so far as to introduce a new tax on alcoholic substances. Gwaine wouldn't be happy about that.

Speaking of Gwaine, he waltzed into the stables as Merlin was mucking them out, treading right through the pile of horse dung that Merlin had carefully accumulated with the intention of shovelling it all away later.

"Her Royal Pratness has a royal stick up her backside today!" was the knight's greeting, spoken around the piece of hay sticking out of his mouth.

"Stop using prat, prat's my word," was Merlin's amused response even as he began scraping at the dung again.

"But what else can I use? 'Chump'? 'Twit'? 'Meatball'? It doesn't quite have the same ring to it..." Gwaine trailed off, spat out the hay and began toeing through Merlin's carefully arranged pile of muddy straw. "What's up with him anyway?"

"Arthur?" Merlin paused, leaning against his pitchfork. "To be honest I've no idea. He just woke up in a really bad mood."

"He kicked Lord Byron out of the courtroom," Gwaine commented.

"Did he?" As far as Merlin knew Lord Byron was a lovely old gentleman. A tad outspoken, but generally someone whose opinion Arthur valued. "What did he do?"

"Nothing, far as I know. Told Arthur he was better off running a surplus budget." Gwaine shrugged. "I suppose everyone has their bad days. Time of the month and all that."

"What?"

"Nothing, nothing." Gwaine laughed at the confused look on Merlin face and reached over to ruffle his hair. "Best sharpen her highness' sword for training this afternoon or in the mood he's in, he may just have your hide."

"Right, right, now if you don't mind, some of us actually work around here." Merlin shooed out the laughing knight, but the smile dropped off his face as soon as Gwaine was out of sight.

What's up with Arthur? He couldn't help but wonder. Had something happened that he wasn't aware of, to throw the monarch's mood so frightfully out of whack.

An hour later Merlin found himself struggling to get to the training yard in time while balancing Arthur's chain mail, helmet, sword and shield. He tripped over a knoll in the grass and ended up sprawled on the floor much to the knights' amusement.

"Ladies and gentleman, Merlin!" Gwaine declared, throwing an arm out. Elyan moved to help Merlin up, but all joviality was gone a moment later as Arthur appeared on the field. The knights watched him warily, obviously acutely aware of his bad mood, but Arthur seemed quite calm, picking up his mail and waiting expectantly for Merlin to help him into it.

"Everything alright?" Merlin asked softly as he dressed Arthur.

"Fine, fine," Arthur replied easily, and Merlin watched him cautiously.

"I hear you had some... heated discussion in court today," Merlin continued.

Arthur shrugged, pulling his helmet on. "It's all sorted now," he said, then added, "Don't worry your little head over it Merlin. These nobles always get so hot and bothered over economics."

Merlin blinked a few times. Before he could say anything Arthur was turning and shouting for the knights to "pair off and begin warm-ups! We'll be working with maces later today."

Because Merlin had a horrible sense of timing, he didn't quite register that despite Arthur's current calm demeanour, the events of today might indicate that he wasn't exactly in the mood to hear about his banished ex-significant-other. As it was, he decided that now was the time to bring it up.

"Arthur," he said, "I have something to tell you."

"What, that you've finally grown brains?"

If anything this jibe only encouraged Merlin that Arthur was back in his usual mood.

"It's about Gwen," he blathered on, and Arthur's face clouded over. Unfortunately, Merlin couldn't see this behind his helmet.

"I've told you not to speak of Gwen," Arthur said lowly, dangerously.

"I just thought you might want to know that she's alright. She's in Ealdor. My mother-"

And here Merlin broke off because suddenly he was on the ground and his face hurt like anything and Arthur's fist was raised in the air and heavens above, did Arthur just hit him? He did. Arthur just hit him.

Arthur just punched him.

Arthur had never punched him.

And that was the moment when Merlin looked up and met Arthur's eyes and saw nothing in them but pure anger and rage. No remorse. Not even surprise.

Something is very wrong here.

A/N: Hope you enjoyed! It's my first time writing for this fandom so I'm a wee bit nervous. Please let me know if anything is inaccurate/OOC :)

Thanks for reading, reviews and constructive criticism are greatly appreciated!