For Matthew Vaughn, a good villain is essential to the success of a Kingsman movie. And after raising the bar with Samuel L. Jackson’s loud, lisping Richmond Valentine in Kingsman: The Secret Service, Vaughn was determined to come up with another character we would love to see being good at being bad.

Enter Poppy Adams, an exiled American crime lord now living in her own personal theme park, Poppyland, found in the wilds of Cambodia. And to play this larger-than-life lunatic, whose grand plans for the world bring her into direct conflict with the Kingsman and the Statesman, Vaughn turned to the wonderful Julianne Moore. Long considered one of the world’s greatest actors, Moore is endlessly watchable and incredibly versatile, notching up an array of stunning performances in Boogie Nights, Magnolia, The Hunger Games series, The Lost World: Jurassic Park and, of course, Still Alice, the movie for which she finally won a Best Actress Oscar.

We spoke to her about creating Poppy’s character, the look, filming on the amazing Poppyland set, and more.

How did you get involved with Kingsman: The Golden Circle?

I’m friends with Colin Firth [with whom Moore worked on Tom Ford’s A Single Man]. I got an email from him saying Matthew wanted to talk to me about the Kingsman sequel. He wanted to know if I liked the first one. I said I did. I loved the tone, I thought it was wildly inventive and funny and he called me and said, ‘I have this idea for the bad guy in Kingsman 2. I want you to play it’. It was all through Colin Firth. He was the liaison.   

So you were a fan of the original?

Oh God, yes. Absolutely. It’s something that felt so very different in terms of its place. It’s a take-off, a riff on spy movies. It’s a genre you don’t see very often. There’s action and humour involved, but there’s a real intelligence as well. You’re playing with the genre so it requires some familiarity with these kinds of movies, and modernising them as well.

What was your way into playing Poppy?

There was a lot there already in the language, in the script. That’s how I can tell whether I can do something or not — what’s the character saying? She’s a funny character and clearly a sociopath. What I loved is her desire. She’s first and foremost a business person and wants to be acknowledged for the great acumen that she has. She’s also very interested in American pop culture and misses it and is desperate to get back. Everything in her world is there to satisfy her need to be at home. That was interesting. It’s playing with classic American ideas within this very British spy world. I thought that was great.

She’s quite a colourful character, with an eye-catching introduction…

No matter how outrageous her antics are, they’re normal in her world. She’s the only character in her world, so she doesn’t know. She’s a megalomaniac in the way that all great villains are. One movie I loved so much growing up as a kid was the original Superman… watching Gene Hackman play Lex Luthor alongside his girlfriend sidekick, they were so funny and so real, but also true villains. That’s a tone I thought of a lot when I was making this.

Is Poppy a hands-on villain?

Not really, no. She doesn’t get her hands dirty. She instructs people to do her dirty work for her. That’s a play on the Bond movies. You have these gadgets where something turns into something, where a shoe turns into a speedboat, that sort of thing. In my case, someone is given an arm that turns into a weapon and I have these robot dogs. There’s a love of possibilities — these people are so rich they can buy anything.

Yet, as outlandish as Poppy is, there’s a real world element to her grand plan. A plan that Matthew has said could incite a lot of debate...

One thing that’s interesting is that the villains in these movies do have a rationale, they’re not just moustache twirlers. Sam Jackson in the first one was an environmentalist who cared more about the environment than he did for human life. In this one, Poppy’s ideas almost sound right, and yet we’ve had to come down on the other side. You feel that she might have a point but she’s also demented and she’s out to make as much money as possible. It’s not altruistic.

Poppy spends much of her time in Poppyland, which Matthew and his production team built for real on the Leavesden lot. What was that like to be able to walk around this incredibly detailed world?

It’s a gorgeous set. The production design was really tremendous. It was so extraordinary. This entire world is sitting in the middle of a jungle, with a movie theatre and a bowling alley and a kitchen, and yet we were sitting in the middle of a big dirt lot. We were outdoors. It was an extraordinary achievement that does give you a sense of place. But I always remind people, we are pretending. The whole thing is pretend. We do that regardless of where we are.

Matthew has described Poppy as ‘America’s sweetheart gone wrong’. That certainly seems to be reflected in her clothes. How closely did you work with Arianne Phillips on the look?

Arianne is awesome. Matthew wanted a very classic American ladylike look. A lot of the ideas he looked at initially were from a very specific time period. Arianne and I, because we are American, understood what he meant, but also wanted to make it timeless. I wanted all the clothes to have a great deal of movement and to have a lot of life in the actual body of the fabric. So there’s an American sense of ease to them. That helped so tremendously. Her look is so American and appealing and ladylike and specific to the United States as a culture.

What was it like to work with Matthew Vaughn?

I really enjoyed working with someone who has such a great imagination and such a sense of the world he wants to create. He’s a natural at tone. It’s a very tricky tone, incredibly unusual, and I was thrilled to enter this world. I love the care he takes and how interested he is in detail. He sees everything that’s going on and wants to get it absolutely right. It’s definitely his baby. He’s very careful with tone. There’s an outrageousness to it, it’s very funny but that sense of outrage never outweighs the threat either. I think he’s kept control of it.