AN: SPOILER ALERT. This story contains spoilers through 5.5 "Disir" And really, you should watch that before reading this.
"The fault dear Brutus is not in our stars/but in ourselves, that we are underlings." -Julius Caesar
That morning the kitchen was empty. In the fields, not a single knight stood practicing. The bustling marketplace was not bustling at all, and the castle was completely devoid of people, save three. (The tavern completely devoid of people save one - and it was not the bartender.) The butcher was not butchering nor the servants serving nor the blacksmith, well, smithing.
Every man stood in the square, for to watch the execution of a friend was not an event one missed easily. And this man was everyone's friend.
The king's voice resounded through the crowd, perfectly composed and without waver: "I have been betrayed before, and more than once. Such is the life of the sovereign. But this is a betrayal we bear most heavily. For from now on, if it should come at all, trust will not come easily. How can we tell if a man is honest and true? If he seems a constantly reassuring presence?" He paused and gestured at the man standing before the executioner's block "Why so was Merlin. Dutifully, naïvely loyal?" he paused again, and it was obvious it was practiced and well rehearsed. "So was Merlin." In fact, this was a speech the king had said to himself all night. "Wise as a man of many years but childish in his joy? So was Merlin," he said, an emphasis on every word, but on "Merlin" most of all.
"And if he should so stand by my side, right hand man to the prince and the king, ten years and never a grievous fault noticed? My closest advisor and my friend?"
Arthur paused, bowing his head. From the multitude, not one drew breath. He raised his head a little and his eyes met Merlin's, dry and unreadable.
"So were you." Even the sun became dimmer as the procession began and the clouds covered it. A single step seemed to take hours until all was interrupted by a wretched cry.
"ENOUGH!" The sound seemed to tear his throat as he shouted it, certainly the loudest and most wretched sound any had heard from the physician. Gaius stumbled forward, and for the first time, Merlin's unreadable countenance cracked.
"Gaius," he said, quietly, firmly. "It's quite alright."
"Defend yourself, boy! Don't just stand there stupidly!"
"There is no defense against magic," Arthur half-shouted, but it sounded like Uther, and some in the crowd glanced back up at the balcony where he stood, half expecting to see the ghost of their former king standing beside his son. Arthur was looking furious again, where he had looked only resigned before. "I have already acquitted you of your crimes, Gaius! Don't make me regret my decision."
"But I regret it already," Gaius snapped, his words almost sobs. In the silence, the deep shaky breaths seemed to resonate. "I have harbored a sorcerer, my lord. And it is a crime I do not repent!"
"Then die with him!"
"NO!" Merlin said, and he stepped in front of Gaius as easily and as swiftly as if he were not held by two guards. "You would lose Camelot's greatest physician, and your greatest advisor."
"To lose two traitors is better than to leave one behind," Arthur said, his voice tainted with strange detachment.
"Arthur, think for a moment!" Merlin exclaimed, and it was a mark of the trust that had once existed between them that the King paused reflexively, before shouting again.
"Shut up, Merlin. I do not seek your counsel anymore!" But he seemed more focused than before, and when he looked at Gaius, his gaze no longer seemed to pass right through. "Take the physician to the dungeons," he ordered, and the guards closest who were not holding Merlin began their escort. "Find Sir Gwaine," he ordered a knight standing guard by the entrance of the balcony. "Tell him to go to the dungeons, where he is to release the man he was meant to be watching. And tell him that in watching the physician, he must make sure the physician doesn't watch this."
Arthur turned back to the scene at hand. "I went to you for counsel. I befriended you. I was willing to die for you. I believed in you, you— you— hypocrite! Do you wish to offer some defense?" he said through grit teeth, spitting the last word and facing his manservant once more. "Or better yet some last words?"
"I do," Merlin said quietly. "I have been a fool, and I am ready and glad to die for it. I have seen your death and in trying to protect you, I have ruined you. I don't expect you to forgive my sentence, I only ask for your mercy —"
"Mercy you were so quick to give that night!"
"A man's last words, sire, you really ought not interrupt!" he snapped, before even he looked surprised, and he took a deep breath and tried to continue. "I… I only ask your mercy… in… your remembrance of me." He paused again, unable to continue, his eyes suddenly glazed and wet.
"Arthur, I really am sorry."
AN: And you can just read that last line as the writer's saying "Audience, we really are sorry." Because God knows that they should be. Last season, Arthur was often an idiot. This season, I'm sorry to say, the wisest of them all has been acting quite foolishly.
The opening speech was inspired by Henry V's "So didst thou!" of three traitors in the court. Shakespeare, of course, made it much more epic than I could hope to achieve.
So. Merlin listens to the dragon and someone becomes super evil. Never heard of that one before. (But really Merlin, if you're going to make a mistake, try not to make it twice.)