Louise Brealey, who plays Gillian in A Discovery of Witches, discusses playing a baddie and shooting that harrowing scene with Matthew Goode.

Q: What attracted you to A Discovery of Witches and to the role of Gillian?

A: I had a call from [Executive Producer] Jane Tranter and Kate [Brooke] who was adapting it, and we had a conference call. We talked through what they wanted for Gillian and from me. They approached us and we had a big talk about what they thought she brought to the show and they made a great case for taking part. I didn’t know the books, but obviously the caliber of the people already involved -- Teresa [Palmer] and Matthew [Goode] and Bad Wolf themselves, it was obvious that it was going to be good quality fare. And you know, it’s quite fun, the idea of playing a witch, even though I get to do very little witchcraft. I didn’t have the books and I didn't know about them, but it seemed like a really top-drawer project. It’s quite nice to play an antihero of some description. [Laughs]

Q: How did you work with the creators to expand on Gillian’s role from the books?

A: Part of that is in the writing, and I think it was interesting to us to not have her as some sort of cartoon baddie. She does betray Diana, but she believes wholly that she’s doing it for Diana’s good. I think it’s interesting because she’s jealous of [Diana] but it’s not to plot her downfall or anything. I think it’s reasonably subconscious in Gillian that she envies her friend. I think she’s frustrated, and we just wanted to flesh her out a bit. I think they were interested in making that a real friendship, and seeing what that might do to the story, if that was someone [Diana] had a proper friendship with and not this random woman she was running back into after awhile — that there was genuine affection and shared history and tenderness between these people. I think it makes it more interesting than just going down this cloak and dagger route.

Q: What was it like for you working so much on the set of the recreation of the Bodleian library?

A: The Bodleian [set] was just mind-blowing. You just felt like you were really in there. When we first arrived, we were doing a read-through or something, we went on a little tour of the studios, because we’re the first production to be on Bad Wolf Studios in Cardiff — which was a factory where they made TVs, and now it’s a film and TV studio which is kind of great. But the paint was literally still wet, and the sound stages were covered on the ground with rows and rows and rows of wooden book spines which were to go into the library. It was mind-blowing the amount of detail that went into it from these guys and gals. And you can see it on the screen, it’s just beautiful. It’s a really good-looking show.

Q: Why do you think Gillian hates vampires so much?

A: Her world is small, and she just can’t countenance the idea that other creatures have the same sort of values. She’s very protective of witches, who are endangered a bit, so she’s very mindful of that and very protective and very loyal. It was important for me to not judge her as a bigot — I mean, she is, but you can’t play someone from the inside while sort of applying that logic to it. She’s just revolted by vampires. She’s never had anything to do with them. She’s loyal to her kind and frightened of them; they are kind of scary.

Q: In Episode 5, Matthew confronts Gillian and attacks her. What was it like shooting that scene with Matthew Goode?

A: It was great -- it was a lot of fun. I was on a wire at one point so that I could be up in the air while he bit me. I’m not suggesting that he couldn’t have possibly held me up there for a long time, but I’m heavier than I look. And we needed certain angles, so I was harnessed and wired up, which was good fun, if a bit chafing in certain parts. [Laughs] So, that was good fun. It was thrilling to do that kind of work. And I’m really pleased with how it came out. It’s really cool. ... And Matthew is a really good laugh as well, he’s great to work with. He’s a clown.

Q: Is Matthew’s attack the last we’ll see of Gillian?

A: I think it was interesting because in the books, she dies, and I think it was difficult having [gotten] to know her a bit, to kill her off, because it would have made Matthew’s crime pretty heinous, even in the context of her transgressions. I think that gave them pause. … So I mean, you know, I’m hoping they’ll bring me back at some point. Deb’s up for it! [Laughs] And she wrote it, so as far as I’m concerned that’s a rubber stamp. I’ll keep my fingers crossed - probably not until that moment because I’ll get major pins and needles, but I’ll cross them every now and again.

Read a Q&A with Edward Bluemel, who plays Marcus.

A Discovery of Witches airs Sundays at 9/8c.

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