User blog comment:Morganaforever/Episode Review: A Lesson in Vengeance/@comment-5364525-20121118021742

I enjoyed this episode, especially Dragoon. Considering the nature of the Arthurian Legends ie, rape, incest, adultery, betrayal, conspiracy, etc, I'm not surprised by the number of times the writers use the traitor-in-our-midst plot device. Especially considering the fact that they can't really use the rape and incest story lines.

Third season there were a number of critics complaining about the formula to every episode- monster/enemy attacks, Arthur gets knocked out and Merlin saves the day, the end. I think that the writers have done well in breaking that mold, even if they have fallen into the trapping of similar story lines. When they said that they were using longer story arcs and moving beyond the contained-within-a-single-episode story lines, I knew that there would be episodes like this.

A Lesson in Vengeance is essentially the middle act of a play. It's main purpose is to add to the rising action/tension of the overall story arc of the season. Guinevere in some legends is portrayed as an opportunistic traitor, not at all loyal to King Arthur, her political match. I personally like where they've taken Gwen this season. They are allowing Angel Coulby to really shine.

So, all in all, this episode had two purposes in my opinion: it gave Merlin an absolute reason to suspect his good friend and it showed us as viewers that Enchanted!Gwen means business. This isn't some Oh-look-Gwen's-enchanted-but-she's-not-going-to-do-anything-bad-because-she's-Gwen story a la Gaius in Goblin's Gold. It's obvious that Morgana is really the one in charge, and that Merlin has his work cut out for him to fix this particular pickle that Camelot has found itself in.