Gwen as the plotter seems very cunning and clever, she quite faithfully imitates Morgana in manipulating other people, especially the always gullible Arthur, and the last scene in which she is believed to be the one to discover the poisoner brings to mind Morgana when she gets the credit for protecting Camelot from the wights and the sleeping sickness when actually she was the one to cause it. Morgana meets Gwen at the market to give her the poison, just like Morgause used to meet Morgana. Though it is a bit silly and risky for Morgana to come to Camelot in the guise of the old Hilda, with whom the knights are very familiar as she could have easily been recognised. Apparently, a wizard or witch using an ageing spell can take only one and the same form as it is the same with Merlin.
Gwen's relationship with Morgana mirrors that of Morgana and Morgause, as this time it is Gwen who is a kind of "padawan" to Morgana, and she learns really quick. Gwen has been charming before but now she uses that and the fact that everybody trusts her to plot against Arthur, and is very effective at that as everyone believes her. She is great at playing the innocent young queen. The murder of the stableboy Tyr was very brutal and cruel for Gwen, I wonder how she would feel about it when the enchantment is removed? I wonder how they will do it? In the review of the previous episode I supposed that maybe Gwen is only pretending to Morgana that she cooperates with her only to turn the tables on her later on, but from what she does in this episode it is clear that she is in earnest. The assassination attempts are very well prepared and executed and not just ploys to cheat Morgana as Arthur would have died had it not been for Merlin's magic. I wonder how they are going to explain Arthur's death at the end of the story if it had been established that Merlin's magic can save from death?
Merlin was really hilarious as the old wizard, cracking jokes and ironic wordplay, and the scene with the cook is passing funny too, though I wondered why he turned back into the young Merlin before reaching Arthur's chambers as it would be easier to escape knights who were a bit scared of the wizard Dragoon but they knew Merlin well and if the spotted him, they would have captured him and put back to his cell before he managed to help Arthur. Though apparently it was easier to climb the walls in a young body ;) When the knights are looking for Merlin hiding behind a barrel I was sure that Mordred would somehow suss him out as a fellow magic user. It is not clear what magic Mordred possesses, as a boy he used some telekinetic magic, but we do not really know what he is capable of.
As for Gwen, she is seriously enchanted but I hoped that as she was sitting by Arthur's (death)bed and Leon was extolling her virtues and telling her how the knights will follow her were Arthur to die, that being praised for something she is not would somehow cause a change of heart in Gwen and that she would abandon her plotting and assassination attempts, but apparently as the trailer of the next episode shows, it is not so. The enchantment must be very strong, I wonder how they would break through it and what they do with Gwen afterwards? Technically, she is guilty of high treason and numerous attempts to kill the king.
The first scene when Gwen and Arthur are riding through the meadows and Gwen says "the three of us", before Merlin appeared I thought she was trying to tell Arthur she is with child, though apparently this is not the case. She needs to hurry up taking into account Arthur's impending death in the last episode.
I wonder what is Morgana's endgame since obviously she wants to take over the throne herself and not allow Gwen to keep being queen, as she told her?