11 September 2025

S4C's acclaimed Welsh-language drama Y Golau (The Light in the Hall) returns with its gripping second series titled ‘Y Golau: Dŵr’ – set to premiere 14 September 2025. The much-anticipated follow-up intensifies the suspense, diving deeper into the dark heart of the fictional Welsh village of Llanemlyn.

One of Y Golau: Dŵr’s leads is Rhosllanerchrugog-born actor Mark Lewis Jones, who has been in high demand recently with a flurry of both Welsh and English-language projects. Mark says he always feels privileged to perform in his native Welsh:

“It really was a win-win experience: the Carmarthenshire backdrop is amazing, and the script and cast were great. You couldn’t wish for more.”

The story picks up against the backdrop of a controversial reservoir expansion plan, which ignites dormant community tensions. A young journalist, Caryl Huws, finds herself tangled in long-buried betrayals and sinister mysteries—including new doubts surrounding Rhys Owen's imprisonment for his cousin Llŷr’s murder during a protest in 1995.

The drama stars Siân Reese‑Williams (Hidden/Craith, Y Sŵn, Hinterland/Y Gwyll) as Caryl Huws; Mark Lewis‑Jones (Chernobyl, The Crown, Dal y Mellt) as Rhys Owen; Nia Roberts (Tree on a Hill/Pren ar y Bryn, Yr Amgueddfa, Hidden/Craith) as Eve Davies and Robert Glenister (Sherwood, The Night Caller, Hustle) as Robert Davies.

Siân Reese-Williams is the only actor reprising a role from the original Y Golau. This time, her character has shifted from the subject of a wrongful accusation to someone determined to uncover the truth.

 “It was really special to come back to the world of Y Golau, even though this series stands completely on its own” explains Siân. “Caryl is in a very different place now — she’s rebuilding her life, training to be a journalist, trying to make sense of the world through truth and justice.

 “Caryl is going through a metamorphosis, which is something I found really fascinating to play. It’s something I think a lot of people of her age are experiencing and not something we see very often portrayed on screen and I really appreciated the chance to do that.  

 “Coming back to play her again, especially with such a new cast and story, felt both familiar and completely fresh.”

 Robert Glenister makes his debut in a Welsh-language production — a first in his long and distinguished career.

 “I’ve always admired the strength of Welsh drama from a distance, so when this came along, I jumped at the chance,” says Glenister.

 “This is my first time working on a Welsh-language drama. I didn’t have to speak Welsh myself, but the bilingual nature of the production was fascinating — and it felt very real. The story is gripping, the writing is sharp, and the cast are just fantastic. It was a pleasure to be part of it.”

 Supporting cast includes Tom Rhys Harries as Hari Breckon soon to be seen in a major role as Clayface in the upcoming DC film, Maeve Courtier‑Lilley as Mabli Davies Owen, Wyn Bowen Harries as Bryn Owen, Mali Tudno Jones as Megan Breckon, Matthew Gravelle as Gareth Breckon, and Gillian Elisa as Eunice.

The series is spearheaded by creator and lead writer Regina Moriarty, with additional episodes by notable Welsh writers: Siân Naiomi, Anwen Huws, Catherine Linstrum, and Angharad Elen.

 Executive Producer Nora Ostler Spiteri praised the collaboration with Long Story TV and APC and thanked S4C, AMC+, Creative Wales, and Channel 4 for bringing the series to life, noting the joy of returning to filming locations such as Llandovery.

 The original Y Golau (2022) was both a ratings hit and widely praised as a gripping Welsh noir.

Y Golau: Dŵr  manages to blend family secrets, political conflict, and atmospheric mystery—an excellent showcase of Welsh-language storytelling.

 Y Golau: Dŵr is set to premiere on S4C on Sunday 14 September 2025, fully in Welsh or can be seen on following Wednesdays on S4C with English subtitles built in.

 With its blend of moody landscapes, layered history, and a plot steeped in suspense, Y Golau: Dŵr promises to be one of the standout drama series of the autumn season. For audiences craving a cerebral, emotionally charged, and beautifully made TV experience—this is the one to follow.

Y Golau: Dŵr is a Triongl, Long Story TV and APC Stories for S4C and AMC+, made in collaboration with Channel 4 and the Welsh Government via Creative Wales.

All six episodes of the first series – Y Golau – can be watched now on S4C Clic and BBC iPlayer.

S4C’s dramas are sponsored by Trafnidiaeth Cymru / Transport for Wales.