Carmarthen-born actor Iwan Rheon has been longing to film a drama in his home country for years, so when Channel 4's Welsh drama The Light in the Hall came along, he grabbed the opportunity to play teenage killer Joe Pritchard.
This isn't the first time that Iwan has taken on the role of a murderer. The 37-year-old became known for playing perhaps one of the most hated TV characters of all time, Game of Thrones' sadistic villain Ramsay Bolton.
WATCH: The trailer for The Light in the Hall
After signing up to play another seemingly cold-hearted killer, it's natural to make comparisons between the two characters - but the reality is, they couldn't be any more different.
Opening up about the new series, which was filmed in both English and Welsh, Iwan revealed what drew him to the fascinating character and how he prepared for one very emotional scene. Keep reading for all the behind-the-scenes details…
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Explaining what initially attracted him to the role of Joe, Iwan recalled: "I've really wanted to do something in Wales for a long time because there have been so many years of waiting for the right projects to come along. I read this and I thought it was fantastic and I was fascinated by the character, so it all sort of came together beautifully. As soon as I read it, I knew I wanted to do it immediately."
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Preparing for the role required some research. Joe, who is released on parole in episode one after serving 18 years behind bars, suffers from dissociative amnesia, meaning he can't remember any details about the murder he was convicted of.
"I think the crucial thing for Joe, for me, was getting to grips with this concept of dissociative amnesia and how that affects his everyday life, which comes as a result of trauma that he's had throughout his childhood," Iwan explained.
"It's that kind of panic and just not knowing what you've done. And even though you believe you've done something, you've been told you've done something having admitted to doing something, you can't actually remember it, and how scary that must be.
"His dad told him all his life that he's a pervert and he's dirty - he believes that. It's really gotten into his head.
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"How that relationship with other people manifests itself, and why he really just wants to be left alone and go and live in a caravan in the woods on his own at 18. That was the kind of general state that I needed to find in order to tell Joe's story."
Joe is a far cry from the malicious Ramsay, whom Iwan portrayed for three years on the HBO fantasy series from 2013 to 2016. Comparing the two characters, he said: "Ramsay is an extrovert who revels in being an [explicit] and genuinely enjoys doing horrible things. Whereas Joe is scared and introverted. He's a quiet man. He doesn't want to be around people. He wants to be left alone. So they're completely different people.
Iwan played Ramsay Bolton on HBO's Game of Thrones
"They just share that one thing in common… or not," he added, teasing a major plot twist.
Reflecting on one particularly tough scene from the series, which sees Joe revisit his father's house where he confronts his difficult childhood in a moving solo performance. Iwan revealed how he prepared for the taxing sequence.
"That was a difficult scene because you're on your own, talking to no one," he said. "At the same time, I enjoyed that. It was a really good challenge. It was one of those scenes where it was at the end of the day on the schedule and you look at that you think, 'Whoa, I'm not gonna have a lot of time for that'.
"So you just kind of go right, I have to be prepared as an actor, ready to just smash it out in one if I have to. It was a bit more like doing a play I suppose."
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Iwan stars opposite Joanna Scanlan and Alexandra Roach in the Channel 4 drama
The actor went on to say that while those emotionally demanding scenes are hard, he doesn't let himself become "too connected" to the character - a skill he learnt from his days playing Ramsay, perhaps?
"I mean, I find where the characters are emotionally through my imagination and feeling and understanding of it. But I don't allow that then to overly infiltrate me in a way," he said.
"I think maybe physically I got quite tense from playing Joe but mentally, I'm quite good at separating the two things. I've had to really," he added, laughing.
The Light in the Hall is available to stream on All4.
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