Steeltown Murders: Why true-crime fans should seek out this compelling Welsh murder-mystery

It’s the case that has haunted Detective Chief Inspector Paul Bethell (Philip Glenister) for almost three decades.

He was always convinced that the 1973 deaths of teens Geraldine Hughes and Pauline Floyd, whose strangled bodies were found by a farmer in Llandarcy woodland after they never came home from a night out in Swansea, were linked to the demise of Sandra Newton two months earlier in Tonmawr.

However, his colleagues in Neath were adamant Sandra’s boyfriend John Dilwan Morgan (Rhodri Miles) was her attacker (“He was married, he had form and he was this close to cracking when we sweated him,” a local detective told Bethell at the time), an accusation he always denied.

“They’re not looking at sex offenders, or her stepfather,” the young Constable Bethell (Scott Arthur) laments of their narrow investigations. “They’re not looking for some PC from Port Talbot to solve it for them either,” comes the pithy reply from a more senior colleague.

But Bethell is not easily dissuaded, especially when Morgan has an alibi for the night when Hughes and Floyd went missing.

Frustratingly though, his boss would prefer he simply focused on their patch: “This is a double murder, there’s no room for idle speculation.”

As the four-part BBC drama Steeltown Murders opens however, Bethell, now in the twilight of his policing career, hears a rumour that the cold case is being reopened.

New technology had allowed police scientists to isolate the male DNA on Hughes and Floyd’s clothing. But with no match in the existing database, some “shoe-leather” and smart targeting of potential suspects to swab is required.

Persuading Detective Superintendent Jackie Roberts (Karen Paullada) that he’s the right man for the job (“If there’s a snowflake’s chance of bringing this man to justice, I will give it a shot”), Bethell knows he has his work cut out for him in finding the killer – with just a limited budget and resourcing.

Fans of true-crime should definitely seek out this compelling police procedural and character study.

Director Marc Evans (Safe House, The Pembrokeshire Murders) and screenwriter Ed Whitmore (Silent Witness, Rillington Place, The Winter King) do a terrific job of criss-crossing between the original murder investigation and the hunt for DNA