Ruth Wilson says Mrs Coulter is more vulnerable and "much more dangerous" in His Dark Materials season two

Wilson said: “Mrs Coulter is much more alone without the support network that she had at the Magisterium and is taking risks and burning bridges. She’s much more vulnerable, and for that reason, becomes quite a lot more dangerous.”

Wilson is no stranger to unwholesome roles: she was the macabre serial killer Alice Morgan in Luther and Alison Lockhart in Sky Atlantic series The Affair. But in His Dark Materials she sought to find different tones in the character who Philip Pullman described as “a cesspit of moral filth”.

“The evil comes out of a love of control,” she said. “Without that, she’s nothing. Look, she does horrific things. I’m not justifying her actions, but as an actor, you have to understand why.

“For me, the biggest clue was her daemon, the monkey. They’re a great team, but when the two of them are alone, how do they interact? They don’t like each other; they never speak; they’re lonely and angry. That the monkey doesn’t have a name or voice suggests that if it’s a representation of self, there’s something Mrs C is repressing or silencing. That’s her driving force.”

Mrs Coulter's troubled relationship with her daughter, Lyra, will grow deeper if not closer in season two.

“After season one, we wanted to maintain Mrs C as the antagonist to Lyra’s protagonist," she said. "In the book she kind of disappears, but Philip gave us licence to dig deeper and explore who she really is – who she may have been before, how she became so powerful in a male-dominated world, and what compromises she made. Her ambition has been at the expense of her relationship with her child. Coming into contact with her daughter is a huge reckoning.”

She is full of praise for Dafne Keen’s performance as Lyra. “Unfortunately, in this season, we don’t have many scenes together. But every time we do, they’re brilliant – the ones that you look forward to, because they’re electric.”

What makes Dafne special? “Fearlessness,” she explained. “She’s fearless and feral. In a good way. When Dafne walked into the audition [in 2016, aged 11], I just thought, ‘Wow’. She’s got something so magical. She’s not intimidated by anyone. She just stared me dead in the eyes, and I thought, ‘My God, she’s going to give me a run for my money’. You can’t imagine anyone else as Lyra. Over two years of filming, it’s been thrilling to be there watching her become a woman.”

Dafne has a different version of their meeting: "At the audition, Ruth came over and said, ‘Hi, I’m Ruth Wilson. We have the same eyebrows’,” she laughed. “I did not know how to react.”

Keen, for her part, revealed that she didn't think she'd want he role of Lyra in 2016.

“I’m very Latin-looking, with dark eyes and hair, and the novels’ description of Lyra is blonde and fair; and I was more expensive [than a British actor] because of flights and housing."

But win it she did and a bonus of filming season two, which wrapped just before the COVID-19 shutdown, was the prospect of filming with Wilson again. “She’s so talented and hard-working. We both get really carried away, ad-libbing and getting crazier and crazier. She helps me to be much more free.”

His Dark Materials season two premieres on BBC One on Sunday 15th November at 9pm.

The new issue of Radio Times featuring the full interview with Ruth Wilson is in shops from Tuesday 3rd November.

Read more about the His Dark Materials cast, the His Dark Materials release schedule and the His Dark Materials age rating, plus find out where His Dark Materials is filmed, including the scenes set in Cittàgazze.

Check out what else is on with our TV Guide, or take a look at our new TV shows 2020 page to find out what's airing this autumn and beyond.