AN: Ever notice that Gwen is usually the one who catches Merlin in his most awkward situations? That is where this one; 'epiphany' came from. That and I think Gwen would be the one who realises Merlin and Emrys are one and the same. Kinda AU for tonight's series finale. CANNOT WAIT FOR IT!
Merlin had had the clever idea of disguising himself as Emrys in order to battle Morgana without giving away his secret. However he didn't count on the knights and Arthur turning up halfway through their somewhat epic magical duel. Merlin's abuse of his power whilst disguised as Emrys; bossing Arthur around; scaring the hell out of Morgana and pushing around the knights was seriously biting him on the backside as they all argued over who had the right to kill him. At least nobody recognised him.
"Sorry to interrupt the big battle but I have just one question." Gwen was standing in the doorway; a sword in her hand and the unconscious figure of Helios lying on the floor behind her.
"What's that?" Arthur asked. Gwen looked at them with a raised eyebrow before looking at Merlin.
"Why's Merlin dressed up as an old man?" Gwen asked.
The knights, Arthur and Morgana looked at one another and looked at Merlin/Emrys and put the pieces together as they realised the truth. All of them turned and advanced on Merlin; ready to pay him back for what he'd done.
Merlin did the smart thing; he ran like hell.