Gangs of London season 3 is welcoming some new faces to their twisted underworld – and Cornelius Quinn is top of the pile.

With his own group of lackeys, a perfect hiding spot at a fairground, and a fuse so short he could blow at any given moment, Cornelius proves to be a force to be reckoned with. He has ambitions of his own that could send shockwaves all the way through the criminal underground.

Speaking ahead of the new series, Richard Dormer talks about Cornelius, his bittersweet relationships with members of the Wallace clan, and why you shouldn’t trust his characters walking stick…

It was a kind of baptism of fire. I was thrown right in there at the beginning, battling in a fairground. I got a terrible cold, and it haunted me throughout the shoot. It was a three night shoot, an ungodly hour of the morning and it was pouring rain and freezing cold.

Elliot and Luan turn up, looking for somebody, and they get the sharp end of my stick. He’s lean and he’s mean, and he’s kind of like a cat, slow moving. But when he has to, he moves very quickly. He strikes like a cobra, and he’s very damaged. He was betrayed by his family maybe 20 years ago and he’s trying to creep back into the power dynamic of the Wallaces.

Yeah. It was one of the conditions I had for joining the show. I wanted one because I’d actually been researching the Shillelagh, but it’s actually a black thorn fighting stick, and it is a lethal weapon. You can break bones and stab with it. Normally it might have a metal point, and sometimes the stem systems are quite blunt. These ones have been sanded down, but it’s for gouging the face and ripping throats. Absolutely lethal.

In 1800s Ireland, the British occupied Ireland and the Irishmen weren’t allowed to have weapons, so they all developed a limp and they started walking around with these things. Plenty met in secret to learn what became a new martial art, because they could defend themselves against bayonets and swords. These things can take a lot of thrashing.

Yeah. I think he kind of wants revenge for what happened to him, but he’s gonna do it in a way that looks like he’s helping them. I think what he wants to be is the kind of kingpin. He wants to be King Rat.

He wants to be in the position that Marian’s in, and because he’s so damaged and broken, the only way he thinks he can feel better about himself is to do the same thing to others that was done to him. So he’s kind of childlike in a way. A mean, angry, lethal child. You never know what he’s thinking. And when he smiles, it’s trouble. (laughs)

I did have fun. I mean, bad guys are good fun to play. But I think you’ve always gotta find something in them that is human to make them accessible to the viewer. I think I did that, just in moments he is quite vulnerable. He’s just a damaged human being like, I’d say, a lot of the characters are in the show. I think he’s got the mentality of a 14 year old teenager. He’s just angry at the world, and at his lot in life.

Yes. In a way, what he’s doing is destroying Billy’s soul. He makes Billy more like himself, but I do think there is a kind of a love there, which is why I just think he’s a deranged character. But also if Billy is meaner and nastier, without a conscience, then he will be more powerful because nothing will stop him to rise to the top - and Cornelius can rise with him.

Season three, to me, seems to be a great unravelling of a system. So the power struggle, it’s changing, and the ground is shifting and we don’t know who’s going to be left standing at the end. Who is going to be the boss? And who is going to fall by the wayside?

I hadn’t seen it but heard it was very violent. When they offered me the part, I started watching. What really sold me was The Travelers in episode two. I just thought that was six minutes of some of the most intense action I’d seen on television. I thought, ‘oh, wow, I want to be part of that, I want to get in on that’. It’s adrenaline pumping just watching it. There’s something about it, even though it’s almost like operatic violence, it feels very real. You don’t often see that on TV because normally it’s… I don’t know, it doesn’t look real. Whereas this is very gritty and you can almost feel every breaking bone.

I think all the best characters, whether they’re mean or they’re wonderful, they’ve all got flaws and good points. So you’ve gotta care somehow, even if it’s just that you like the way they wear their hat.

It was great. I just think Hong-Sun is very funny, so we had a lot of laughs. He always used to greet me every day, going, ‘Richard, you’re so cool.’ He really liked my character, because he just said, ‘the character gives very little away, which makes him kind of attractive in a way.’ You know, he’s an enigma. But also the character enjoys what he does. It’s an enjoyment rather than a practical thing. He actually enjoys his work.

Speaking personally, just the way that we work together, he would be talking and I could just understand. Not telepathically, but I just knew what he meant. He knew that I knew who the character was, and he would never ask me to do something out of character. So it was a kind of understanding.

I love working with him. He left me alone quite a lot to make all my own decisions, but he brought out something in my interpretation of the character because the words didn’t get in the way, it just became like a kind of a shorthand, but it really worked. It’s not about the words, it’s about what’s not said. It’s a ‘show don’t tell’ kind of thing.

Yeah. It seems like since Game of Thrones, since Ned Stark died, there have been a lot more major characters in TV dropping like flies. I don’t think that was really a big thing, ten years ago. So I think that Game of Thrones really brought about that kind of twist: that no character in television, even if they’re a big name, nobody’s safe.

Bloody. Dynamic. Relentless.