Katie McGrath spoke to Digital Spy about what we can expect to see from her character Morgana in Series 4. Here’s some highlights.

Will Morgana be an out-and-out villain in series four?

“You’d like her to be, wouldn’t you? I think everyone is waiting for that! It’s funny, it was the number one question I used to get asked over the first three series. When is she going to be bad? When is she going to go over to the dark side? It’s one of those things, because everybody knows where [the characters are] ending up, they’re kind of desperate for you to get there! What I liked about it was that it wasn’t going to be so obvious, how she gets there. I would love if people could see Morgana’s point of view, that she is a victim of her circumstances. If you had been persecuted by one group of people and accepted by the other, then you’re obviously going to side with the ones that accept you and turn against the ones that are persecuting you! That’s what happened to her, so when you say she’s a villain, I may not exactly agree with you, but I see it from your point of view because, yeah, Merlin’s the good guy. Great! So technically yes, Morgana would be his foil. Not necessarily evil, because evil’s just a point of view. But for the purposes of the show… this is a really roundabout way of me saying, ‘Yeah, she’s the villain!’ But I’m trying to make my case at the same time. She’s the misunderstood bad girl!”

Is there a part of you that misses playing the ‘good’ Morgana?“No, I love a bad girl! Absolutely. I couldn’t wait for her to become like this, because at the same time that she became the bad girl, she became powerful. All her uncertainty goes. In the first series, she was the opinionated, spoiled princess, and then in the second series, she was very unsure of herself. In the third series, she was still playing both sides. So by the time we get to the fourth series, she’s got to where ultimately she’s going to go. But in typical Merlin fashion, it’s not what you expect. It’s never what you expect, and in series four, it isn’t either. But I like the fact that she is strong and she’s accepted who she is. She’s assured, and even if you don’t agree with her point of view, she’s committed to it. She believes that she is doing the right thing and that she is saving people like her. She wants to bring back the old traditions, so she will no longer have to hide. I really respect that in somebody, that she is committed to what she believes. To be that strong and powerful is great, especially when you’re a girl. Without being a weak woman and soft, she’s still feminine. She’s a great woman to play!”

Series four will take place one year after the events of series three. What’s changed in that time?

“I think I’m bound to silence! I’m not sure what I can say. Well, Morgana has entirely changed in the year away. She’s been out of Camelot, and she’s probably been hunted and had to hide who she is. So to go from being such a privileged woman to being a hunted fugitive is going to change her. It’s going to make her harder, stronger and more committed. A year has also passed with everyone knowing that she is magical, so that’s also going to have changed how everybody else views her and how she views herself. I’m quite lucky. I’m probably completely biased, but I always say that I have the best character in the show. From season to season, I think she’s changed the most, and this season is no different. I know that everybody will be shocked by what she does in the first two episodes, and how she looks. It’s a complete new image for her. Very cool!”

Morgause appeared to die at the end of series three, so will Emilia Fox be back?

“Yes! Nothing’s ever the way it seems!”

And is there any chance of Mordred returning?

“I’d like Mordred to be back. He’s such an integral part of the story. I don’t know if he’s going to be back, because we’ve only got the first three scripts. But I’d like to think that at some point over the next few years, he’ll turn up, because you can’t tell the story without him. But again, what’s nice about Merlin is that it’s never going to be what you expect, so you can’t think that you know the legends. Even if you do, the show will trip you up and you’ll get a surprise! But I hope he’ll be back. Although [Mordred actor] Asa [Butterfield]’s off working with Martin Scorsese! I love it, we’re so proud of him! That boy, we’ve seen him grow!”

What teasers can you give about series four?“I know we say it every year, but every year it’s true. This series is darker. Very much so. It’s also much more filmic, because we’re actually shooting on 35mm film. I’m not sure how many other TV shows do that. It looks just gorgeous, absolutely wonderful. What else can I say? Another member of Arthur’s family comes in, so he becomes a part of it. Obviously my story is slightly separate from everyone else’s, because I’m no longer in Camelot.”