It was early in the morning and Gaius had woken both Will and Merlin extremely early. Both boys groaned, shouting at the old physician to give them five more minutes but he had been relentless, pulling off their blankets and ordering them to get changed. Within a few minutes, Will and Merlin trudged in for breakfast and the three went off into the lower town.

"Why are we here again?" Will asked, rubbing his eyes free of sleep.

"Because I have been told there is a very sick man in the lower town that needs my attention," Gaius informed them as they walked out of the castle gates and across the drawbridge.

"And why are we here?" Will said, nudging Merlin who was yawning and practically falling asleep on his feet.

"Because I might need someone to carry him," Gaius replied. They reached the area in question and Merlin suddenly awoke at the sight of the poor man they had been called to attend. He had clearly died a few hours ago, his skin milky white and his veins blue. Gaius knelt down to inspect the victim.

"Aren't you scared?" Merlin asked, suddenly waking up as Will crouched next to Gaius to also examine the body. "That you might catch something?"

"I am the court physician," Gaius replied. "It's my job. Besides, most of the time there is nothing to be scared of." It was then that Will turned the poor man over and revealed his terrifying white eyes.

"You were saying?" Merlin said. Will glanced up at Gaius who met his eyes, nodding in understanding at the silent communication that went between them. Working quickly, Will grabbed a spare bit of rug from the side of the road and covered the body, getting Merlin to help him carry it to a nearby wagon so they could get it back into the castle unseen. The last thing they needed was for people to see the body and panic to spread about a plague. The brothers worked together to push the wagon back up to the castle, Gaius just ahead of them.

"What are you doing?" Gwen suddenly asked, appearing from nowhere as the three were about to go through the main gates.

"Oh!" Merlin said in surprised, moving to cover the body even more. "Just-er-moving something."

"It looks heavy," Gwen said, smiling.

"It's nothing really," Merlin assured her. "Oh, someone got you flowers?" Gwen glanced down at the violets in her hands and blushed.

"Oh, no, no one likes me like that," she giggled. "Would you like one?" Behind Gwen, Merlin could see Will rolling his eyes, pretending to throw up as Merlin and Gwen talked. Finally, after accepting a flower from Gwen which he tucked into his scarf, Merlin managed to take his leave and follow Will and Gaius back to their chambers.

"Someone has a secret admirer," Will smirked, bumping his shoulder against Merlin's once they had hefted the body onto the examination table.

"Oh shut up!" Merlin hissed. "It's not like that!" Will only nodded but a grin spread across his face. Merlin knew that there was no way Will was going to drop this now and he internally groaned at the hell he was going to go through once they had finished their jobs for the day. Luckily for Will, Merlin didn't get the chance to snap at him as Gaius had started his examination.

"I have never seen anything like this before," he said, taking a few samples of the man's skin and hair. "I don't think this is a plague. Something like this cannot come from nature. But who has that kind of power?"

"You think it's caused by magic?" Merlin asked.

"Perhaps," Gaius answered.

"Wait a minute," Will suddenly murmured. He stepped towards the body, crouching down on his knees at the head of the man. Merlin didn't stop him despite fearing that Will might catch whatever this was. His brother clearly had some sort of feeling about this and he found it best to stay out of it, especially now as Will's hand fell upon the man's face and his whole posture suddenly went rigid.

"Vision," Merlin said, grabbing Gaius and pulling the old man away just in case. Will's eyes rolled into the back of his head as the Vision overtook him, his whole body shaking. Merlin pursed his lips as he watched. He had seen many of Will's Visions over the years and knew that they could last anywhere between a few seconds to an entire day. He'd have to tell Jem where Will was if it lasted long. At that moment, a hand hammered on the door of Gaius chambers.

"Merlin!" Arthur yelled.

"Damn it," Merlin muttered, scrambling towards the door and opening it before Arthur could enter. "Yes, I'm on my way. Sorry I'm late," Merlin said, angling his body so Arthur couldn't see what was going on behind him.

"Don't worry, I'm getting used to it," Arthur muttered. He looked down at the flower tucked in Merlin's scarf and creased his eyebrows. Merlin swallowed and grabbed the flower, hiding it from sight. Arthur shook his head before speaking.

"Tell Gaius that my father wants to see him now," he said before turning on his heel and walking off.

"I heard," Gaius said as Merlin closed the door. Merlin wanted to argue that Arthur should have told Gaius himself considering the physician was standing right behind him, but Merlin had bigger things to worry about as Will suddenly gasped and hurtled backwards, his eyes widened in what looked like blind panic.

"Will!" Merlin cried, running towards his brother and trying to calm him down from the Vision. He placed his hands on his shoulders, giving Will something steady to ground him to the present time. Their mother had done this a countless number of times before, just knowing that Will sometimes struggled to differentiate between the future and the present when he first came out of a Vision.

Surprisingly, Will recovered relatively quickly but before Merlin could convince him to lie down for a moment, his brother had scrambled to his feet and was out the door in moments. "What on Earth-?!" Merlin exclaimed. He looked at Gaius who seemed troubled.

"Let us go to the council chambers," he said. "Perhaps Will went up there." Merlin nodded but he was still worried. He hated that panicked look Will had on his face and could only hope that whatever he saw wasn't as bad as it might be.

He and Gaius hurried to the council chambers where many of the courtiers were huddled together, crying and looking pale at the collapsed figure on the floor. Gaius was forwards in an instant, crouching down at the body of the male courtier. He was dead, that much Merlin knew, but he still had the strange pale skin and blue veins like the first man did. It was clear that the sickness was spreading and whatever it is, it was spreading first.

Just to the side, Merlin saw Lady Tessa clutching Lady Morgana's hand as the two women recovered from their shock of seeing the courtier collapse. Behind them, Sophie was tending to Lady Jessamine who apparently had fainted although none cared at that moment. But Merlin couldn't see Will or Jem anywhere.

"What happened to him?" Uther demanded, gesturing to the body.

"I don't know, sire," Gaius replied. "This is the second case I've seen today. I was just now attempting to find the cause."

"And what have you concluded?" the king asked.

"It is too early to say, my king. The scientific process is a long one."

"What are you concealing from me!?" Uther was on the verge of pure rage but Gaius seemed unfazed by it. The old man just sighed.

"I haven't seen anything like it, sire," he said. "The victims are becoming infected and dying within twenty-four hours. I would say the most likely cause at this time is sorcery." Uther's face drained of blood as there was a scared murmuring among the courtiers. Quickly, the king pulled Arthur aside and Merlin dutifully followed.

"You must find who did this," Uther told Arthur.

"I will," Arthur replied, looking solemn.

"We need Gaius to find a cure. He needs all the help we can give him. If Gaius is right, believe me, this city will be wiped out. This is the kind of magic that undermines our authority, challenges all we've done. If we cannot control this plague, people will turn to magic for a cure. We have to find this sorcerer, and quickly." Merlin has never seen the king look so unnerved before. In a way, Merlin couldn't blame him. If this was what evil sorcerers could do, then part of him didn't blame Camelot for being so scared of magic.

Throughout the day, Arthur had the guards and nights conduct searches throughout the town. Dozens of people seemed to be falling sick and it pained Merlin to know that he had to power to help them and yet couldn't. More than once he begged Gaius to let him cure someone, to let him use his powers for good but time and again Gaius refused.

"They're suspicious of everyone!" the physician had hissed to him, grabbing hold of his ward to pull him away from a sick man. "You'll only get yourself caught and killed! This is not the time to be using magic!"

Merlin couldn't help but disagree but as he saw Arthur break down the door to another house, he quickly hurried away before arousing suspicion.

It was late evening when Will finally came back. He trudged into his and Merlin's room, looking pretty exhausted. Merlin himself was tired after spending most of the day doing experiments with Gaius to find the cure and trying to hide all evidence pf his magic from Arthur when he came in to search Gaius's chambers. But the moment he saw his brother walk in, he knew that Will was a lot worse off. "You alright?" he asked Will as the older boy collapsed into bed.

"Hmm."

"That wasn't an answer."

"Shut. Up."

"Will. Answer me."

There was silence for a moment and Merlin thought that Will had gone to sleep. But then, the older boy pushed himself up and turned onto his back, facing the ceiling. "The Vision," he said quietly. "It showed me something. Something I didn't want to see."

"What?" Merlin asked. "Is it something to do with the sickness?" Will nodded.

"I think so," he said. "I saw...I saw me crying. Just me, no one else around. But I was crying and holding a hand that was so pale and cold, just like the people who are sick. I don't know who it was though. I don't know who I was crying over. That's why I ran this morning. I thought...I thought..."

"You thought it was Jem," Merlin finished for him. "And...was it?"

"No," Will said, shuddering. "It wasn't. But it could be anyone. Anyone I care about. And that's what scares me the most."

"We'll figure it out," Merlin replied, lying back on his pillows. "We'll stop it from happening."

"That's the thing, little brother," Will sighed. "My Visions don't work like that."

***

Arthur entered the council chambers and approached his father cautiously, knowing that what he was about to say would not please him. "We searched everywhere, father," the prince said. "The entire city. I don't know where else to look."

"I want you to impose a curfew," Uther replied, his face stern and cold. "No one is to be allowed onto the streets after the great bell. And cordon off the lower town. We must isolate this disease and stop it from spreading."

"That's your plan?" The voice came from the back of the throne room and sliced through the heavy silence. Arthur turned, the blood draining from his face as he saw Jem enter the room. "You want to isolate the disease? It's a magic disease! You really think the sorcerer won't find a way!?"

"Watch your tongue when you talk to me, James," Uther spat.

"No, I will not," Jem replied, his voice equally filled with venom. "Not when people's lives are at risk. You want to abandon half of the city!"

"Don't you think I haven't considered it!?" Uther roared. "What else can I do?! I have to protect the rest of Camelot!"

"No," Jem said. "You want to protect yourself." Before Uther could say more, he whirled around and was gone. Arthur looked between his father and the door, his mouth gaping. Quickly making his decision, he haphazardly bowed and practically ran out of the chambers after Jem.

"Jem!" he called, quickly catching up with his brother who was making his way up the stairs. Jem stopped but did not look at Arthur. "What was that about?"

"He can't treat people like they don't matter," Jem said through gritted teeth. "He can't forget or hide the people that are of no use to him. I won't let him."

"He's trying his best," Arthur tried to defend his father but found he couldn't.

"He isn't," Jem assured him. "He's greedy and suspicious and awful." They had made it up the stairs now but Arthur couldn't help but notice how out of breath Jem seemed. His face was pale and his forehead glistening with sweat.

"Hey, are you feeling alright?" Arthur asked, worried that his brother may have been having an attack.

"I'm fine," Jem muttered. "It's nothing. I'll take my medicine and be fine by the morning." Arthur wanted to argue more but the look on Jem's face said that the discussion was over. So Arthur didn't say anything and only made sure Jem made it back to his chambers for the night. But as he went to bed, his mind was in turmoil about everything Jem had said. Perhaps he was right after all.

***

"What's different about this victim?" Gaius asked Merlin and Will the next morning as they stood over yet another body.

"Er...she's a woman," Merlin said. Behind him, Will face-palmed and shook his head, groaning.

"Sometimes I do wonder whether you're amgical talents were given to the right person," Gaius sighed as Will covered his mouth to stifle a laugh. "Anything else?" Merlin looked well and truly stumped so Will decided to step in.

"She's a courtier," he said.

"Yes, and courtiers seldom go down to the lower town," Gaius replied. "So the disease isn't spread by contact."

"They also eat different food," Merlin mused. "And they don't breathe the same air so..."

"Water," Will said. "They share the water..."

"Oh no," Merlin said. "It's the water, isn't it?" Gaius hands him a bucket and promptly tells them both to go to the water pump and get a bucket for him to analyse. The brothers agreed that they would need to be quick and set off in haste.

But as they arrived at the water pump and filled the bucket, Gwen suddenly went flying past, tears streaming down her face as she went. "Gwen?" Will called, already running after her with Merlin dragging the bucket behind them. By the time the boys made it back to Gaius's chambers, Gwen was sobbing in the arms of the old physician.

"Please, Gaius," she cried. "My father is all I have! Please, I am begging you!"

"I have no cure yet, Gwen," Gaius said softly. "I am so sorry." Gwen just sobbed again and ran form the room.

"There must be something we can do," Merlin said. "There has to be."

"Let's hope the water can provide answers then," Gaius said, sighing heavily.

"But that would be too late!" Merlin protested.

"I fear you might be right." And that was when Merlin hatched a plan.

***

Gaius woke Merlin and Will up early the next morning, telling them that the King had demanded for a meeting to update him on how far they had to go before finding a cure. He told them to meet him afterwards so they could go back down to the town. Merlin was in an oddly happy mood, humming his way around as he cooked breakfast and made his bed.

"What's gotten into you?" Will asked him as they walked down the corridors to meet Gaius in the council chambers. "Don't you know there's a plague." Merlin just shrugged, a secret smile tugging on the corners of his lips. Will froze, looking at him as a funny feeling washed over him. "Merlin. What did you do?"

"Nothing," Merlin said defensively.

"Merlin!" Will exclaimed.

"Okay, fine," Merlin sighed. "I went out and cured Gwen's father last night."

"You did what?" Will hissed, grabbing his brother by the shoulders and yanking him into an empty alcove. "Are you completely insane?! You have no idea what could have happened! You could have been caught!"

"I wasn't though," Merlin pointed out. "And Gwen's father is cured. It's okay." Will dropped his face into his hands.

"No," he murmured. "No, it's not...You don't understand what you've done..."

"Nothing is going to happen, Will," Merlin said, stepping out into the corridor again. "I promise." Will wanted to grab him again but they were needed in the council chambers and he really didn't have time to kill his brother (as much as he would have liked to) so he stayed quiet and followed, praying to the Heavens that Merlin's stupid actions wouldn't get them killed.

But, unfortunately for him, the consequences were so much worse.

As they entered the council chambers, Gaius quickly grabbed them both, pulling them into the crowd. "What have you done?" he whispered to them furiously.

"What?" Merlin asked. "What's going on?" Will suddenly grabbed his arm, his grip like a vice as they turned their attention to the front of the room. The King was standing in front of his throne, looking down on the crumpled form of a girl that lay at his feet. Arthur stood next to him, looking extremely uncomfortable at the entire situation, especially as Morgana was glaring at him with fury in her eyes. Jem sat on his own throne, his fingers digging into the wood in apprehension, his face pale and his breathing ragged.

"Gwen..." Merlin whispered. "Oh no..."

"Please listen to me, I have done nothing!" Gwen was begging, looking up at the King. "I swear I've done nothing! Why will no one believe me!"

"I believe you," Morgana said, stepping forwards to defend her maid. "Her father recovered. Perhaps this disease is not always fatal."

"And what of this poultice that was found then?" Uther spat. "It was found in this witch's house under her father's pillow. Now, sorceress, undo the enchantment."

"I can't!" Gwen cried.

"I will show you no mercy," the King warned.

"Father," Jem said, rising to his feet but gripping onto the arm of his throne. Will narrowed his eyes. Jem seemed a little unsteady on his feet. Maybe he should check on him when all this was over. "This girl has been in Morgana's service for years. Why on Earth would she want to start a plague now? She is no witch."

"Silence, James!" Uther snapped. "I have had enough of your antics already." He turned back to Gwen, looking down on her with disgust. "Undo your sorcery, wench! If you do not, I must find you guilty."

"I can't!" Gwen repeated, sobbing her heart out.

"Therefore, under the circumstances, I have no choice but to sentence you to death!" Uther announced, sending shivers down Will's spine. "I can only hope that when you die, this evil plague dies with you."

"No!" Jem cried, pushing himself between Gwen and Uther. But even he could not stop the guards from dragging poor Gwen away to the dungeons. "I will not let you murder an innocent girl! She is not the cause of this!"

"She is not innocent, James," Uther said venomously. "She is the reason so many people are dead!"

"Gwen is my maidservant," Morgana said. "I've seen the way she works. Her fingers are worn, her nails are broken. If she was a sorceress, why would she do this?"

"You have no right to question me!" Uther roared. "I have a responsibility to take care of this kingdom! I take no pleasure in this!"

"Stop lying!" Jem yelled, a thin sheen of sweat breaking out over his forehead. Will took a nervous step forwards, knowing that Jem was over-exerting himself. "You love nothing more than to burn people of magic! You hear the work magic and you no longer listen to reason!"

"He has a point, father," Arthur stepped in. "Yes, maybe she used magic but it was to stop her father from dying. I do not think that makes her guilty of creating a plague. One act is of kindness and love and the other of evil. I don't believe evil is in this girl's heart."

"I have witnessed what witchcraft can do," Uther said. "I have suffered at its hand. I cannot take that chance. If there is the slightest doubt about this girl, she must die or the whole kingdom may perish."

"If this kingdom is to perish, it will be by your hand, father!" Jem cried. "It is your injustice that is the evil in this world! And I refuse to stand by and-" Jem suddenly cut off, causing everyone in the room to look at him. Will felt a sudden lurch in his stomach, his heart twisting as he let out a shaking breath. From next to him, Arthur took a tentative step forwards, laying a hand on his brother's shoulder.

"James? Maybe you should go rest for a while," he said softly.

"No," Jem muttered. "No...this isn't right...I have to stay...I..." He didn't get to say much more. Will watched in horror as Jem's eyes rolled into the back of his head and his knees buckled, Arthur catching him as he slumped to the floor.

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