Starring Alex Roach (The Iron Lady), Dennis Kelly’s enigmatic new six-part thriller Utopia begins on Channel 4 at 10pm on Tuesday 15 January.

> Order Series 1 on DVD on Amazon.

When an unconnected set of people find themselves in possession of the manuscript for a legendary graphic novel, their lives brutally implode as they are pursued by a shadowy and murderous organisation.

Explain a bit about what Utopia is all about…

“God! Okay. I play Becky. She’s a student, and she’s interested in this manuscript, Utopia, because her father died of a man-made disease, and Becky’s inherited it. She believes the manuscript has some answers about the disease. So she joins a forum online and starts discussing the manuscript with the different members of the forum. And then it comes to light that there’s a second manuscript that is rumoured to answer the biggest conspiracy theories of the 20th Century. One of the members of the forum says that he’s got hold of it and a group from them agree to meet up in the pub to look at it.

“It’s an eclectic bunch of strangers, but as soon as this book falls into their hands, they’re lives implode and they are suddenly on the run from a company called The Network, who don’t think twice about doing these horrible things. They come after the group because they want the manuscript as well. So the group has to go on the run.”

What made you say yes to the role?

“What normally happens is that my agent sends me a script, and I look at the first 10 or 20 pages, and my instinct kicks in, and I say yes or no. With this, I sat down just to look at the first 20 pages, and I didn’t move for four hours and read all six episodes. I read it back-to-back, I couldn’t even go to the loo, I needed to read the next bit, find out what happened next.

“I don’t think I’ve ever had that with a script before, where it was so gripping. Dennis Kelly’s writing was brilliant. I also think he writes for women so well. All the female characters in this are very strong and feisty and full of personality. As soon as I read Becky, I could see her in my brain, and I could see how she was going to say her lines.

“I got really excited, which is really scary as an actor, because you haven’t been offered the part. I had to have four rounds of auditions for this – it was more than getting into RADA! I cancelled a holiday and everything just because I wanted this so much. I was so thrilled when I actually got it.”

Are you a fan of graphic novels?

“Not really. I didn’t really know much about them before starting this. I’ve got a cousin who’s into this sort of thing, and she showed me her collection. I can see the thrill of them. We were all given a copy of the Utopia manuscript when we finished filming, and it is so dark and mysterious. I think that’s the vibe of the whole series as well. The stories and the fabulous artwork really fire the imagination.”

The series is quite full-on – it doesn’t pull many punches, in terms of brutality, does it?

“No. I found it exhausting to film, because being on the run from halfway through episode 1 onwards was a lot. We were filming in Liverpool for four months, and every day was really full. The stakes are always really high for the group, there are no scenes where you can really relax and take a back seat. It takes a lot out of you, filming for four months like that. You’ve got to have so much energy; you can’t go on the back foot.”

Were you able to have fun amidst all the intensity?

“Yeah. I’ve had more fun on other sets, in a way, because this required a lot of brain power, and used up so much energy. Because the story is so complex, and we were shooting it out of sequence, it was really hard work. But we all made friends and had a really good time together. We were all in this apartment block in the middle of Liverpool, and we were just thrown together, a bit like we are in the series.

“On my first day on set, I had to do a sex scene with Nathan. When you start a new job anyway, you get nervous, so I was a bit nervous anyway, and then I had to take all my clothes off and pretend to have sex with this guy that I didn’t even know yet. So it was those kinds of situations that really bonded us. If you don’t laugh when you’re doing it then you could go mental. We all had a really good time together. I loved working with Nathan, who I’d seen in Misfits, and Adeel, who was hilarious in Three Lions.”

Everyone in your family seems to be in the police force – how come you didn’t go down that route?

“They are! My father was a policeman, my brother and sister are both in the police force. I remember going to church on Christmas Day when I was three, and I took a dustpan and brush with me, because of all the presents I had received, that was the one I wanted to take. And while the service was going on, I was pretending to be a cleaner, and cleaning up under everyone’s feet.

“I made this character up, and I think that’s when my parents began to realise that I wasn’t going to go into the police force. I just loved making up characters from a young age, really. I can’t imagine how scary it must be sometimes being in the police force. The stories my brother and sister tell me that they have to deal with in South Wales – I’m definitely happier acting!”

Do you ever worry if you’re on a raucous night out in Swansea that you’ll be faced with your brother or sister coming to arrest you at the end of the evening?

“That would be the worst case scenario – or, I suppose, the best case. They’d probably just let me off. When I know that they’re working in Swansea, I definitely just put my head down and keep walking.”

You started off acting n Pobol Y Cwm. How did you end up in that?

“I was about 11, and I just went over to my mate’s house on a Saturday and knocked on her door to see if she wanted to come out and play. And she said she was going to a drama club with her sister, and did I want to go? So I went along, and that day they were doing an open casting for Pobol Y Cwm. I’d never really acted before, and I just gave it a go and got the part. I think that’s why I’m so comfortable on sets now, because of all the hours I put in as a child.”

Is Welsh your first language?

“I’m bilingual. I speak Welsh with my dad’s side of the family, and with my mother’s side of the family I speak English. I think I’m more comfortable in English now, but when I was younger it was maybe the other way around.”

Are you proud of your Welsh heritage?

“Oh yeah, I’m as Welsh as a mountain goat. I love going home, the people that I love most are back home. I’ve also got loads of Welsh friends in London, and we meet up and, stereotypically, we go and watch the rugby and sing songs.”

What do you miss about living in Wales?

“Mainly my gran – I speak to her nearly every day. And just talking to strangers. When I moved to London, I found it really alien that people didn’t talk to each other. I got on the bus once, and was on the way home, in my first week at drama school, and I was feeling really homesick. And it was dark and rainy, and the bus was packed. And this old guy got on and started giving abuse to these 11-year-old girls, it was really horrible. And no-one was saying anything. And I just stood up and was shouting at everyone “You should all be ashamed of yourselves! If my dad was here, he would have done something.” And then I just started crying.

“I was so homesick when I first moved up here. But it got better. I’ve fallen in love with London a bit now.”

Obviously I have to ask you about playing the young Margaret Thatcher. What was that like?

“It was amazing. It was my first feature film, so turning up on set and having a dressing room next to Meryl Streep was kind of testing for the nerves. But I remember driving in to Pinewood for the first time, and Meryl being there, and me walking in and thinking “I’d better go over and introduce myself to her.” And I went over and she just turned around and went “Darling!” and threw her arms around me. She’d seen my audition tapes and had been involved in casting me. She made me feel so at ease. It was exceptional, working so closely with an idol of mine.

“Playing a real person, I got to do a lot of research, and changed my voice and the way I walked. And because it was a period drama, the costumes were amazing as well. It will always be a very special, happy memory for me. And I must admit, seeing where she came from, and what she achieved, in the era that she achieved it in, I couldn’t help but admire her.”

Talking of playing strong women, you’re also playing the queen soon, aren’t you?

“I think that’s going to happen next year. I’m going to play the young Elizabeth. It’s based on the true story of her and Margaret being allowed out of the palace to mix among the people on VE Day. No-one knows what really happened that evening, so this is a romantic take on what might have happened that evening.”

Is it nice to be playing someone both contemporary and Welsh in Utopia?

“Yeah, definitely. I must have one of those faces that fit into period pieces, I’ve done quite a few now. So to have a role where I could wear modern clothes and make-up and hair, I loved it. And to be in my own accent as well is one less thing to think about. It was challenging in different ways, though.”

In 2011 you were named in Screen International’s list of Stars of Tomorrow. How did that feel? Is it exciting, or a pressure?

“I didn’t know anything about this list previously, and then I looked into it and saw who they’d picked in previous years. I didn’t feel any pressure, I just felt really excited that somebody would see me as someone who’s going to go places. I love being on these up-and-coming lists. When they stop coming through, I’ll be quite sad, because it’ll mean I’m getting old, and people are getting used to me.”

> Order Series 1 on DVD on Amazon.

Watch the trailer…

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