“I feel like Mrs Coulter is a bit of a control freak,” says Ruth Wilson on stage at the London premiere of His Dark Materials. “She needs to be in control, and that’s in her look as much as everything else.” Mrs. Coulter’s look in the HBO-BBC adaptation is a striking one. Inspired by 1930s-1940s Hollywood actor Hedy Lamarr, it oozes glamour and shine. Wilson’s costumes feature bold tailoring in luxurious velvet, satin and fur, with jeweled accents. They’re clothes that assert her character’s wealth and status while accentuating her physical attractiveness – a source of power she deliberately exploits in the male-dominated spheres in which she operates. Operates is the word for it; Mrs. Coulter’s actions are surgeon-precise. An intelligent and skilled manipulator, she calculates exactly what to do, say, and—yes—wear to achieve her ambitions. Those clothes, for instance – they’re not just designed to look chic, but also to serve a dreadful purpose. They are, after all, what first attracts Lyra to her at Jordan College. “I wanted her to be soft,” explains Wilson. “I wanted fluffy, touchable hair. We talked about the clothes being tactile, so velvets and satins and sparkly for children. I wanted her to be approachable to children,” she laughs. “Well, she’s got to attract kids!” After His Dark Materials Episode 2, viewers know why. Mrs. Coulter is the head of the General Oblation Board (oblation means an offering to God), an organization whose initials have led to it being mythologized among the Gyptian children as child-abductors “The Gobblers.” Funded by the tyrannical religious ruling authority the Magisterium, the board has been kidnapping children and is preparing to take them North for a series of dark experiments. In Episode 2, Mrs. Coulter visits the imprisoned children in her fairy godmother guise, taking down their letters home and promising them an adventure to “the best place you could possibly go to.” Once out of sight, she drops the façade, burns the letters and strides away, a conscienceless aberration in a glossy dress. Mrs. Coulter’s daemon mirrors her clothing. A golden monkey with shining, soft fur, on the outside he’s exactly the kind of animal a child might be drawn towards. On the inside though… well, that’s the question. Nameless and voiceless, Mrs Coulter’s daemon is a very different prospect to most. read more: His Dark Materials Creator Discusses Religion in TV Show Viewers found that out in Episode 2, when Lyra and Pan discovered that the golden monkey had been spying on them through Lyra’s bedroom grille independently of Mrs. Coulter (usually, daemons can’t stray more than a few yards from their human without causing intense discomfort to both). Wilson explored what this extraordinary ability means for the character of Mrs. Coulter while preparing for the role. She worked with puppeteer Brian Fisher – who operates the on-set monkey puppet (later replaced by CG animation by Framestore) with which she performs – to work out the psychology of Mrs. Coulter, how separation occurs and what it feels like for the pair. Wilson rehearsed moving in a simian way to reflect the form of her daemon. “I found a bit of inner monkey in me,” she tells the crowd at the BFI Southbank. “You’ll see when monkey comes out of me. It’s fun.” Fun isn’t quite the word when it happens on screen. Wilson’s mercurial performance in the show is unnerving. She flashes from (a facsimile of) warmth to ice-cold in an instant, switching, as Wilson says in this HBO featurette, between from fairy godmother, Snow White, and wicked queen – a one-woman fairy-tale by the Brothers Grimm. Her range makes Mrs. Coulter “mysterious and unknowable and constantly unpredictable,” says Wilson. It was a joy to play, she explains, “because each scene you can keep switching and going this way and that way and confusing the audience and confusing your fellow actors. She’s a master manipulator, she knows what she’s doing, and she’s incredibly intelligent and driven and she wants what she wants.” Power and control, at any price. As a hint, she’s described as “the mother of all evil” in a series by The Guardian on literary baddies that ranks Mrs. Coulter alongside The Lord Of The Rings‘ Sauron, Medea, and H.P. Lovecraft’s Cthulhu in the pantheon of fictional wrongdoers. Is Wilson ready to be a baddie in family households around the world, she’s asked by BFI panel moderator Rebecca Nicholson. “Absolutely”, she laughs, joking, “My nieces and nephews won’t want me to babysit again – I’m okay with that!” What does Wilson make of a description by another character in book three of the series, The Amber Spyglass, which calls Mrs. Coulter as “a cess-pit of moral filth”? “That’s glorious!,” she laughs. “Usually you get ‘blonde, curvaceous, mid-30s…’ this is ‘cesspit of moral filth!’ I know how to do that one!” His Dark Materials airs Mondays on HBO. Find out more about the TV series here.