Arthur has just about given up hope when the far wall begins to glow – it heats and scorches and there's a strange sort of light bursting through the cracks. He can hear men screaming, can hear metal screeching on metal, can smell the blood tainting the air. His captors are terrified – they stare at the wall as though it has come alive, the rock writhing and melting and contorting into twisted shapes. Arthur holds his eyes half-shut, and pretends to still be unconscious.
And then the wall explodes inwards in a flash of golden light.
Merlin stands like some sort of avenging angel in the doorway, pieces of stone whizzing away from his body, sparks and whirls of ethereal light twirling around his outstretched fingers. Arthur can't help but stare at him - his whole being is alive with magic, his eyes shining and his skin crackling, and even in his rough clothes and slightly dirty hair he looks magnificent. And on his face is an expression of such fury and righteousness and power that the Prince nearly shuffles back where he is slumped on the floor.
"You don't know what you have done," Merlin tells them in a low voice, but as low as it is it's raw with force and it's not a threat. It's a simple fact, and it instils a terror in Arthur that his bones feel but his heart doesn't.
His captors don't have time to take another breath before Merlin's eyes harden, his head dipping ever so slightly, and a pulse of energy ripples through the room. Arthur closes his eyes against it as it thunders past him in a haze of static blue light accompanied by a roar to match any beast. Where it hits the bandits, they fall like stones, their bodies crumpling and falling to the floor like rag dolls.
And then as quickly as it began, it's over.
Merlin looks at Arthur and he squeezes his eyes shut, allowing his limbs to relax, although his heart is racing like it's never done before and every muscles in his body is screaming for him to run.
Arthur risks peeks at his men and his manservant as he's carried out, and they are as horrified as he is. One or two try to attack him but they are gently rebuffed, swords falling harmlessly to the floor, unable to get within three feet of him. Merlin has slung him over his shoulders and is acting as though he weighs nothing more than a small child - his feet and steady and sure on the cold stone ground.
He sets him down carefully, leaning him up against the wall, and raises one hand. And there comes the wave of fear, accompanied by something opposite and warming and indescribable.
And then there is nothing.
Arthur wakes to birdsong and soft sheets and the scent of honey, and if it weren't for his memories, he would not know that he had been held captive for several days. His pains are gone, his brands and wounds healed, and he feels better-rested then he has done in a long time. He does not know how long he has been sleeping.
"How are you feeling?"
He turns to where Merlin is cleaning in the far side of his room, and shrugs as he pulls himself up into a sitting position.
"Good. I feel good," he admits, and Merlin smiles. "I don't remember escaping though."
"Your father sent out a search party, your knights brought you back," he says easily, and Arthur finds himself nodding along.
"Yes. Of course they did."
It comes back to him in flashes and glimpses.
Sometimes it's during the day - an action that stirs a memory hidden within himself, a phrase or a tone of voice that sounds familiar. But it's like holding onto the memory of a dream and it slips through his fingers as soon as it surfaces, tantalisingly close but too far to recall. He knows that something isn't right. He knows that there is something that he doesn't remember.
But the life of him, he cannot work out what.
He remembers light.
He remembers fury.
He remembers fear.
He remembers death.
He remembers Merlin.
Eventually, he works it out. It takes many weeks but the memories build on each other, each one strengthening in his mind as another is added until they're coherent enough to retell those lost hours to him. They were well-hidden, he won't deny that - layers upon layer of magic hiding them away, burying them deep and disguising them as childhood fantasies, wards preventing him from accessing them. Because it seems that as willing as Merlin is to alter his memories, he won't so far as to destroy them.
He doesn't confront his manservant. Instead, he watches Merlin act as though nothing has happened, as though this is a common occurrence, and he thinks that maybe it is.
He sits awake at night, long after he has sent Merlin away for the evening, and thinks. He considers his life from the moment that Merlin entered it, all awkward limbs and sharp tongue and dazzling smile and a determination to save his life at inopportune moments.
The more he thinks, the more he realises that this is a common occurrence.
He says nothing - he just continues to watch Merlin.
When Merlin tells him, seven months later, he pretends to be surprised. He pretends to be offended, to feel duty-bound to tell his father, to feel betrayed. He spends several hours building up arguments against Merlin only to have his manservant effortlessly break them down, one by one, and with each argument he takes a step closer to Arthur.
Arthur threatens him, curses him, screams and rages and cries at him, releasing everything that he's been holding onto since he remembered that day.
Merlin is silent and unyielding in front of him and when Arthur has shouted himself hoarse, his eyes dry and his soul exhausted, the warlock takes him into his arms and strokes his hair.
Once Arthur has calmed and they are sat curled on the floor, Merlin tells him that he knew the spell had failed. He knew that Arthur remembered.
Something within Arthur is set free and when he breathes again, it's a breath of everything that is to come.