Interview: Merlin's Katie McGrath

TV's Morgana speaks exclusively to SFX about the upcoming fourth series of Merlin - and mentions Krull , Darth Vader and George RR Martin along the way

Katie McGrath is utterly charming as she chats to us backstage at this year's Comic-Con. She's full of smiles, must be the best dressed person we've seen for days, and wryly teases us for our pink camera tripod (yes, it's pink) before wowing us with her knowledge of everything from Buffy to Bond. You can read some more of this interview in an upcoming SFX but here are the highlights:

SFX: Merlin 's coming back for a fourth series this year. Of all the characters you probably have one of the biggest story arcs...

Katie McGrath: Do you know why that is? Because I have the best character [laughs]. I may be biased. I think you're right, from where she starts to where she ends up it's the biggest change - and for me as an actor that is challenging. It also means that I don't get bored! Because I haven't played the same character from year to year. She was a spoilt, stroppy princess at the start. She's an unsure, fearful girl in the second. She's on both sides in the third... and now in the fourth she's just Darth Vader! You get the best of all worlds. You keep the audience interested. I always used to say she was the ticking time bomb of the show and everybody was just waiting for her to go off and by the fourth series you're getting to the point where she might be ready to explode! And I think that makes it really exciting. That's the great thing about Merlin , because you know where everybody is going. You're waiting for it to happen, but because the show is the way it is, things never happen in the way you expect. It never gives you Lancelot or Excalibur like you think. You're not going to get a Guinevere like you think. So, even if you are a huge fan of the legend you can still watch the show and be surprised as much as if you know nothing about it. You can watch it and be entertained and I think that's what makes it work.

SFX: Do you enjoy being the show's Darth Vader?

McGrath: Wouldn't you? Seriously, I love a bad girl. Who doesn't?! She's fun to play. She's far more confident. People ask me sometimes if I'm at all like my character... and I'm not! But she's the girl I wish I was. She's very confident, she's very opinionated and she's very in control - and intelligent. She's all of those things. She happens to be a little malevolent, possibly [laughs]. But, you know, we all have our off days. She's got very good reasons for doing what she does.

SFX: Your character knows "Emrys" is going to be her downfall. Do we discover more about that in this series?

McGrath: He's a very large presence to her. She doesn't know who he is but he is a very fearful presence for Morgana - and a driving force for her throughout series four. It's a big deal, that Emrys problem! Her need to discover who he is and ultimately vanquish him is a big part of what she does going forward. But I think she believes she'll get there in the end. She doesn't know who he is, just that he is out to get her and that she could ultimately be destroyed.

SFX: Does that mean there are going to be big battles in this series?

McGrath: It's all bigger than anything we've ever done. It's funny: when we started the first season it was built in this old washing machine factory! It had five sets on it, five little sets. As every year went on they would build more sets. Now that we've got to the fourth series the place is chock-a-block. I mean it's huge! There is a massive green screen; it's bigger than you can imagine. We shoot much more on location now too. I had a sneaky look at the first ten minutes. Remember Krull or Conan The Barbarian ? Bleak, large, stony, open landscapes? That's what this feels like. Or Willow . Those big fantasy epics that used to be made. Well, I was just thinking of Merlin , "I can't believe this is TV!" We're shooting on 35mm film now. We're shooting much more on location, in Wales, than we ever did before. It just feels like they've expanded the whole world. All of Camelot feels bigger. The whole "fantasy genre" aspect of it, the whole entire universe of Merlin just feels much larger . We're part of something that I don't think has been seen on TV for a long time. I don't quite know how the producers are getting any sleep! I know I'm not getting much.

SFX: You mentioned some of the fantasy classics there. We love those 1980s films. Merlin 's been on TV for four years now and recently there has been another rush of fantasy on TV and film with Camelot and Game Of Thrones and the new Conan and so on. Have you seen any of this newer stuff?

McGrath: Camelot I didn't watch because even on your best day nobody wants to be compared to Eva Green! When she was announced I was like, "Oh no." [Laughs] She's a Bond girl, the best Bond girl of the last 15 years! So I haven't watched that. Game Of Thrones I haven't watched yet because I promised my brother I would sit down and watch it with him. But I've read all the books and it is one of my favourite things. It is stupendous and it's the type of thing that HBO do well but at the same time it's nothing like Merlin . It's not even in the same box so it's one of those things I think I will watch for pure enjoyment.

SFX: It would struggle to get Merlin 's timeslot...

McGrath: I think it possibly would [laughs]. There are a few storylines that might not work at 6:30 on a Saturday night, do you think? They could give it a go. Give the population an education. They're excellent stories; and the next book is out now! I'm excited!

SFX: Thanks Katie!

Merlin returns to BBC One in October this year. Check out the official site at the BBC . In the US, Merlin airs on Syfy . You can read an interview with Colin "Merlin" Morgan in issue 213 of SFX , on sale from Wednesday 24 August, and there are already a couple of videos on this site of Morgan and co-star Bradley James talking about series four. Read more of this interview with Katie McGrath in SFX magazine when the series is broadcast.