Merlin had stopped showing up to council meetings, and any time one of the more senior members made a comment about his absence, Arthur silenced them with a withering glare. He himself barely saw the sorcerer, and when he did it was easy to tell how Gaius was doing without even entering his chambers. Merlin's hair might have been a little unruly before but now it was absolutely wild, and there were dark rings under his eyes as if he hadn't slept since the party returned to Camelot.
Gaius was getting worse.
One morning Arthur stopped by, announcing himself with a cursory knock on the door, and Merlin bolted upright from where he had been slumped over a table. There were innumerable bottles littering the surface in front of him, most emptied, some turned on their sides or even shattered on the ground nearby as if in great frustration.
"Arthur," he beamed, but it was wan and tired. "I'm sorry I haven't been in lately, I—"
"How's Gaius?" Arthur asked softly, and any pretension of a smile fell from his friend's face. Merlin led him to the bed in his old room.
"I moved him up here so he wasn't disturbed when people came in asking for herbs," he explained. "He's been like this for the past few days."
Gaius was propped up with a generous amount of very fluffy pillows (Gwen had brought them from the royal stores personally), a stack of books at his side. He looked almost as if he'd fallen asleep reading, but the rattle Arthur had heard when he first fell ill hadn't gone away. In fact, it had grown noticeably louder, and he saw Merlin flinch at each ragged intake of breath. It sounded like a death rattle.
"Nothing I've tried is working," Merlin said bitterly. "I've tried my magic and every potion he's ever taught me. I even brought in a few of the Druids from the village, and he's still the same."
Arthur didn't know what to say, but the pain stamped across the sorcerer's face resonated in his own chest. He'd known Gaius all his life. No matter what Uther or Arthur had said or done, the old physician had never been anything but loyal and wise. Arthur respected him more than any other man alive, save Merlin, in the kingdom.
"You'll figure something out," he offered, but Merlin didn't seem to be listening.
"He's always taken care of me," he sat heavily in a stool at Gaius's bedside, and Arthur got the impression that he had spent many a night in that same spot. "And now that it's my turn I can't… I…"
Merlin's face contorted and for a moment Arthur didn't understand what was happening. The sorcerer's hands flew up to cover his mouth and he rocked slightly in the chair, and Arthur heard a stifled sob.
Another moment passed and Merlin seemed to catch hold of himself. He pressed a palm into one eye, swiping away at the tears there even as another rolled, uninterrupted, down his other cheek. Arthur was suddenly overwhelmed with an unshakeable idea that Merlin was used to hiding his sorrow, and he felt a twinge of shame. Tactfully he walked across the room, pretending he was looking at the books piled high at Gaius's bedside and not at the sorcerer.
"He's still taking care of me, you know?" Merlin spoke after a few minutes. His voice was husky, and he cleared his throat, and when he spoke again he sounded almost normal. "All he does when he's awake is research. He's trying to figure out how to stop… whatever's happening to me. Says it's more important than a cure for himself." He laughed wryly. "Geoffrey brings the manuscripts to him every morning. It's funny, I'd never seen him outside of the library before."
"Has he found anything yet?" Arthur picked up an ancient tome, flipping through it. There were strips of parchment marking a few pages, but the language was unreadable to the king.
"No," came the reply, but it wasn't Merlin's voice. The young men both turned to find Gaius hoisting himself a bit higher on the pillows, his face sallow but his eyes bright. "Not yet, but I have the entire Royal Library to search."
"You need rest," Merlin protested, but he was genuinely smiling for the first time since his mentor fell ill.
"As do you, my boy, from the looks of you." He clucked, shaking his head slightly. "No matter. You can help with my research." He grabbed a book, handing it to Merlin, and then turned, smiling, to the king of Camelot. "And so can you."
He took another book for himself and flipped to a page marked with parchment, impervious to the expression on Arthur's face—a curious mixture of surprise, resentment, and admiration, which Merlin found hilarious. He smirked, but tried to look deeply absorbed in his own texts as Arthur shot him a kingly glower.