The Light in the Hall actor breaks down "mental gymnastics" of filming show in both Welsh and English

This season follows Sian Reese-Williams's character Caryl, now a journalist, investigating the case of Rhys Owen, played by Mark Lewis Jones. Rhys was imprisoned for the murder of his cousin Llŷr during a protest against the expansion of a reservoir in 1995. Now, he's been freed – but Caryl wonders whether he may actually have been innocent all along.

Jones spoke with RadioTimes.com exclusively about the series, and in particular spoke about how the series is filmed in both languages, and about his experience of doing so.

"It works per shot," he explained. "This is the most economical way of doing it, time-wise. You just do it shot by shot. So each shot, we’ll do that in a language – doesn't have to be English first, but let's say it's English first – we'll do that in English, and then when everybody's happy with that, we then switch to Welsh.

"So we effectively do another two or three takes in the new language, and then we’ll switch, we'll go to a new shot, but we'll stay in Welsh. We'll do the new shot in Welsh, and then we'll switch to English, but you flip flop like that all day. That's how it works. I talk a lot about this, but obviously people are fascinated. It's become our norm, in a way, now we're so used to it."

Jones continued: "Effectively, for us actors, it's learning the same scene twice. It is double the amount of learning, so we have to really be on top of things, because on a TV or film set there's no time. There's no extra time to give the actors a 10-minute break to go through things, so we have to just grab each other when we can and run through the new language.

"Because your brain is constantly flip-flopping from one to the other. You get into the groove, especially when you're rehearsing in one language, and everybody's feeling it, and it's nailed, and director’s happy, actors are happy, everybody's happy, and then you have to move to a different groove.

"So it's a bit of mental gymnastics, but it works, and in these times of strict and tightened budgets, it's a way of getting Welsh-language stuff made and two for the price of one, in effect."

While the first season of The Light in the Hall starred Joanna Scanlan, Iwan Rheon and Alexandra Roach, this new season sees Reese-Williams return alongside a whole new cast, including Jones, Nia Roberts and Robert Glenister.

During his chat with RadioTimes.com, Jones revealed that it was actually his friendship with Scanlan which led him to watch the show's first season - meaning he was "thrilled" when the opportunity to star in season 2 came along.

Y Golau: Dŵr will premiere on S4C on Sunday 14th September, while the English-language version, The Light in the Hall: Still Waters, will be released on Channel 4 at a future date.

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