Arthur stood in shock as he saw his wife scramble to cover herself more fully. Her eyes glistened with tears when she saw her husband.

“Arthur,” Gwen squeaked. “I-”

The rage that covered his face stopped her short. He couldn't decide who he was more furious with: his cheating wife, or the man he loved as a brother. So instead he turned to Merlin. “Get me Sir Leon and Sir Gwaine.”

Merlin nodded, mouth shut. He ran out of the room and down the stairs to Gaius’ chambers. The entire castle seemed awake since the warning bell, and in fact dawn was drawing near. He reached his chambers soon enough, bursting in without a knock.

“The king needs Sir Gwaine and Sir Leon in his chambers!” He panted, out of breath and still confused.

Leon and Gwaine, who had been talking quietly with Gaius, spun around alongside Percival and Galahad. Their faces betrayed their confusion, but they did not object.

“What's wrong?” Gwaine asked as he hurried with Leon and Merlin to Arthur’s rooms.

Merlin wouldn't respond with anything meaningful. “The king will explain.”

First to enter was Leon. He found Lancelot standing, dressing himself. Guinevere stood in a nightgown, tears streaming down her face. Gwaine came in moments later with Merlin. The King had his sword out.

“Take them to the dungeons,” Arthur spat furiously. “Separate cells.”

Leon and Gwaine turned to Arthur in shock, mouths agape, uncertain as to what had prompted this. But they didn't question him. Gwaine took Gwen by the arm, pity in his eyes as she shouted for Arthur not to order her there. He escorted her out, and Leon soon followed with Lancelot.

Lancelot glanced back at Arthur as he left. “Thanks to your wife, Morgana will now know all your plans for war.”

Arthur drew his sword and would've struck Lancelot where he stood had Merlin not interfered.

“This is Lancelot,” Merlin begged. “Let me see if I can help him.”

Arthur’s face contorted in rage but he nodded. “You have till dinner. He’ll be executed then.”

“Yes sire.” Merlin bowed and followed Leon down to the dungeons.

By the time they got there, Gwaine had already placed Gwen in a cell and was locking the door. Leon put Lancelot in a cell not far away.

He turned to Gwaine as the deed was done. “He's working for Morgana.”

Gwaine seethed in anger as he looked back at Lancelot. “That bastard.”

“I don't think it's Lancelot,” Merlin told them quickly. “Something’s wrong with this. And it's too much of a coincidence that everything happened tonight.”

They turned in surprise as Galahad came bounding down the stairs. “Merlin, Gaius says he might've found something about Fira!”

All three followed Sir Galahad quickly up the stairs and down several hallways to the physician. They burst inside, eager to hear whatever news he had. Light now made its way from outside into the rooms, dawn breaking.

“What is it?” Merlin asked.

Elyan and Percival shrugged and gestured to Gaius. The old man beckoned for them to enter the room further. They took seats where they could find them. Gaius picked up something from the dining table and held it in his hand. He opened his palm to reveal a red rock.

“We found those,” Gwaine nodded. “Back when we interrupted the caravan to Dunnottar. Why?”

“This is a Heart Stone.” Gaius handed it to Merlin so he could retrieve an old, worn spell book. He showed them a picture. “The High Priestesses used them to influence unruly apprentices.”

Merlin glanced up in alarm. “How does it work?”

“According to the book, a spell is used to fuse the stone to the person’s body. It secretes a toxin into the bloodstream which reaches the heart and takes control.” Gaius sighed. “It leaves the victim incredibly susceptible to suggestion from the caster.”

“You said unruly apprentices,” Leon pointed out. “Doesn't that mean they were at least somewhat willing to undergo the process? Fira wouldn't have.”

Gaius nodded. “I imagine Morgana needed her extremely weak for it to work on Fira.”

“We left her to this,” Elyan murmured, putting his head in his hands where he sat at the table.

Gwaine left the room, slamming the door behind himself. He strode with purpose to the training fields. There he found a practice dummy and showed it no mercy.

“Gwaine!”

The knight turned to find his brother Sir Gaheris walking towards him. He had his sword out and a guarded expression on his face. He pointed the sword at Gwaine.

“Do you want a real partner?” He shot him a rueful smile. “The king won't be happy to see his practice dummy in pieces.”

Gwaine looked at the dummy and a laugh formed. He chuckled before turning to Gaheris. “I'd welcome an easy target.”

Gaheris laughed heartily. “Oh please. I beat you half the time.”

“Keep telling yourself that.” Gwaine winked. He raised his sword and nodded for them to begin.

As they traded blows, Gaheris spoke up again. “Galahad brought me up to speed. Fira isn't your fault.”

Gwaine smashed his sword violently against his brother’s in anger. “Then whose is it? It was my patrol.”

“Kara’s. It was an ambush she set up,” Gaheris struggled and managed to push Gwaine away. “And she’s dead because of it.”

Gwaine swung left but Gaheris caught the strike easily. The latter parried back before swinging himself with an uppercut. Strike, parry, block, strike. They both knew the delicate dance of swordplay well.

As they sparred, the warning bell rang once more. Gwaine and Gaheris looked at each other and ran towards the Citadel. Gwaine decided to head towards the dungeons and his brother followed. With swords out and ready, they skidded to a halt at the top of the dungeon stairs. Merlin called to him from behind.

“It's Fira!” He panted and blew past the knights. “She dropped her warding spell!”

Gwaine and Gaheris followed him into the dungeons. They took the steps two at a time, rushing with all their speed to catch the fallen warlock. But by the time the three reached the cells, all they found was a swirling wind as Fira and Lancelot whisked away.

Two knights, sirs Philip and Lamorak, lay dead in the hallway, strangled. A guard had a slit throat further along. Guinevere huddled against the wall and sobbed.

“What have I done,” she cried.

Gaheris crinkled his nose. “You betrayed your husband and king.”

“Did you tell Lancelot anything about the war?” Gwaine squatted down in front of her cell door. When she refused to look at him he snapped. “Gwen?”

“Yes.”

“Shit.” Gwaine stood up and shook his head. “I need to find King Arthur.” He looked down at his dead brothers-in-arms and then to Gaheris. “Take care of the bodies.” He then beckoned for Merlin to follow.

They found Arthur pacing in the Round Table room. Leon, Elyan, Percival, and Galahad sat with him, waiting for their king to speak.

“Lancelot’s gone.” Gwaine reported as he walked inside. “It was Fira. She broke him out, killed Lamorak and Philip.”

Arthur slammed his hand on the table. “Damnit. And Guinevere?”

Gwaine was about to speak but Merlin cut him off. “I believe she was enchanted, sire. I tried to figure out what spell it was but couldn't. Definitely done by Fira.”

“Really?” Arthur’s face softened slightly. “But did she betray any information?”

Gwaine nodded. “She says so.”

Arthur walked around the room in silence. The others watched him carefully, wondering what was going on inside his head. Trying to formulate a plan, he smiled slightly before dropping back into a frown.

“Merlin, what do you think happened to Lancelot?” Arthur folded his arms over his chest. “Is there any part of the real Lancelot in there?”

Merlin sighed. “Probably. Now that he completed his quest, I'd imagine his old personality, or parts of it, might behind to resurface. Why?”

“He loves Guinevere.” Arthur frowned. “Always has.”

With hesitation, the servant nodded. “Yes.”

“Then Guinevere must die.”

The room exploded into questions and objections. But Arthur merely held up his hand for silence and stared them down.

“We will stage an execution. Lancelot, if I know him well like I believe I do, will not permit Gwen to die.” He continued to explain his plan. “Hopefully he will come and we will capture him and some soldiers of Morgana.”

“So you won't kill Gwen?” Merlin hoped he heard the King correctly.

Arthur shook his head. “No. But she must not know it's a fake. It needs to seem real. Two days from now, she will be hanged.”

Everyone present swore to secrecy. They split and went their separate ways, the knights heading to the Rising Sun despite it being but midday. Meanwhile Arthur and Merlin had to deliver the sentence to their Queen.