New true-crime drama ‘The Pembrokeshire Murders’ begins on ITV on Monday, with critically acclaimed actor Luke Evans leading the cast in the three-part miniseries which explores the pursuit of a cold-blooded serial killer by the Dyfed-Powys police force.

Adapted from the true-crime book ‘Catching the Bullseye Killer’ which was written by the real Welsh detective chief superintendent Steve Wilkins and ITV news journalist Jonathan Hill, the mini-series depicts the detective’s pursuit of serial killer John Cooper who infamously appeared on TV’s ‘Bullseye’ quiz show in 1989

It covers the re-investigation of the brutal double murders in the Welsh county of Richard and Helen Thomas and Peter and Gwenda Dixon.

Three days before Christmas in 1985, the charred remains of siblings Richard and Helen Thomas were found in the ruins of their remote Pembrokeshire farmhouse, Scoveston Manor. Four years later, husband and wife Peter and Gwenda Dixon were ­murdered as they walked along the Pembrokeshire Coastal Path.

All four victims had been shot at point-blank range and it was clear the cases were linked. Yet despite a huge police investigation, the killer remained at large for 20 years.

Then in a cold-case review that began in 2005 the case was finally cracked, thanks to advances in forensic science - and a vital clue in murderer John Cooper’s appearance on game show Bullseye near the time of the second murders.

Speaking about his lead role in the mini-series, Luke Evans said: “It is a privilege to be playing the role of Steve Wilkins in The Pembrokeshire Murders and working again with Simon Heath, his team at World Productions and ITV.

“It’s a huge responsibility for me as the drama depicts a true crime which to this day still affects the families of those whose lives were tragically taken.”

On filming in Pembrokeshire, Luke continued: “It’s just a magnificent place to be at anytime of the year, the juxtaposition of these terrible things alongside the dramatic coastline is incredible.

“It was wonderful, I miss being home very much. I have such a close connection to Wales and it was lovely to be surrounded by authentic Welsh people, rich accents and wonderful characters.”

Starring alongside is Keith Allen, who looks set to give a chilling performance as the killer, and the actor who was born in Llanelli said that he revisited Pembrokeshire to research the role and tweak his accent.

“I was worried about my accent. I used to work in Tenby running boats during the summer, so I went back there on a Sunday and just sat in pubs listening to people talk but they were full of Mancs, Scousers and people from Birmingham watching Sky Sports!”

“So what I did was drive out to Cooper’s village and walk around the area, then I went back to Tenby and that got me in the groove.

“When you’re playing a real person, you can’t take your eye off the ball. But I’m a bone idle actor, I’m not the type of actor to be affected, but when you’re playing a real person, who did these terrible things, you do end up taking that character home with you.

“I’ve never met him but I think I’ve seen enough of him, when you know what he did you can watch him lying on the police tapes and it’s fascinating.”

The cast also includes Tenby born actor Charles Dale, Owen Teale as Gerard Elias, Alexandria Riley as Ella Richards, Caroline Berry as Pat Cooper, Oliver Ryan as Andrew Cooper and David Fynn as Jonathan Hill.

The Pembrokeshire Murders was one of the lucky productions that wrapped just before the coronavirus restrictions came into force in Wales and across the UK back in March.

Filming took place in Wales, with shoots on location in Pembrokeshire and also on set in Cardiff. Scenes were filmed in Goodwick and Fishguard and along the coastal path. The series received funding from Creative Wales.

Roderick Seligman at World Productions, said: “After shooting the series Born to Kill in 2017, World Productions was delighted to return to Wales to shoot The Pembrokeshire Murders in association with Welsh production company Severn Screen.

“With the help of Welsh Government support we were able to film the entire series in Wales, and showcase the best of Welsh talent on both sides of the camera.

“In addition to the seven week shoot, all picture and sound post-production was also done in Wales, at Cardiff-based Cinematic.”

Deputy Minister for Culture Sport and Tourism, Lord Elis-Thomas, said: “The creative industries have been hit hard by the coronavirus pandemic. Throughout this period, Creative Wales has worked hard with our stakeholders to understand the impact, and to respond rapidly.

“There’s no doubt that it’s been a very tough time for the global screen industry with the pandemic bringing television productions across the world to a halt.”

The drama will air on three consecutive nights at 9 pm on January 11, 12 and 13.