Philip Glenister and Steffan Rhodri lead the cast of the BBC's latest prestige drama Steeltown Murders, which depicts a real murder investigation that unfolded in Wales in the 1970s and early 2000s.
Three young women – Sandra Newton, Pauline Floyd and Geraldine Hughes – were murdered in 1973, leaving the county of Neath Port Talbot shaken to its very core.
Though justice could not be served at the time, a second chance emerged decades later when advances in DNA testing brought new suspects into the fold.
Glenister and Rhodri play DCI Paul Bethell and DC Phil 'Bach' Rees respectively, two detectives who were instrumental in bringing the case to a belated close.
Here is your guide to the Steeltown Murders cast, ahead of the show's premiere on BBC One and release as a box set on BBC iPlayer tonight.
Philip Glenister plays DCI Paul Bethell
Who is Paul Bethell? Paul is one of the key figures in the investigation into three murders committed in the 1970s. The case went cold decades ago, but advances in DNA technology ignite fresh hope it could yet be solved. Having first encountered the case towards the start of his career, Paul jumps at a second chance to finally bring the culprit to justice. The job requires facing up to some hard truths from both his professional and personal life.
What else has Philip Glenister been in? Glenister earned acclaim for his performance as Gene Hunt in the BBC's sci-fi police drama Life on Mars and its sequel Ashes to Ashes. Other memorable projects include psychological thriller Mad Dogs, supernatural horror Outcast and period drama Belgravia.
Scott Arthur plays young Paul Bethell
Steffan Rhodri plays DC Phil 'Bach' Rees
Who is Phil 'Bach' Rees? Phil is one of three detectives working for South Wales Police on Operation Magnum; a reopening of a cold case involving the murder of three young women in 1973.
What else has Steffan Rhodri been in? Rhodri will be instantly recognisable to comedy fans as Dave Coaches in the BBC hit Gavin & Stacey, but he has also worked extensively in drama. Recent credits include The Last Kingdom, House of the Dragon, We Hunt Together, and ITV's Manhunt, which shares the same writer as Steeltown Murders.
Siôn Alun Davies plays young Phil 'Bach' Rees
What else has Siôn Alun Davies been in? Davies is best known for Welsh drama Hidden, while he has also appeared in Netflix fantasy series The Sandman.
Gareth John Bale plays DC Geraint Bale
Who is Geraint Bale? Geraint is the third detective enlisted for Operation Magnum; a risky and exhausting plan to uncover the identity of the killer known as the Saturday Night Strangler.
What else has Gareth John Bale been in? Viewers may recognise Bale from Sky Christmas special Roald & Beatrix or BBC comedy-drama The Indian Doctor, which starred Sanjeev Bhaskar in the lead role.
Keith Allen plays Dai Williams
Who is Dai Williams? Dai is the step-father of one of the young women murdered in Neath Port Talbot in 1973. Initially, he was considered a prime suspect in the case, which piled further trauma onto what was already an unimaginably bleak situation.
What else has Keith Allen been in? Allen is known for his roles in Trainspotting, Eddie the Eagle and Kingsman: The Golden Circle. On the small screen, he has appeared in Jed Mercurio's Bodies, Robin Hood, Marcella and The Pembrokeshire Murders. He is the father of singer Lily Allen and Game of Thrones actor Alfie Allen.
Sharon Morgan plays Pat Williams
Who is Pat Williams? Pat is the mother of one of the young women murdered in Neath Port Talbot in 1973, who has become disillusioned by the failure to find justice.
Nia Roberts plays Karina Bethell
Who is Karina Bethell? Karina is Paul's wife. Their marriage has at times been put under considerable strain by his attitudes to work.
Elinor Crawley plays young Karina Bethell
What else has Elinor Crawley been in? Crawley played Princess Cecily in The White Queen and Thyri Haraldson in Vikings.
Priyanga Burford plays Sita Anwar
Who is Sita Anwar? Sita is a local woman who had been friends with the victims before their tragic murder. The loss still haunts her decades later.
What else has Priyanga Burford been in? Burford has recently appeared in Channel 4's Before We Die, Sky's Avenue 5, ITV's Innocent and BBC Two's Industry. She also had a role in the latest James Bond film No Time to Die.
Natasha Vasandani plays young Sita Anwar
What else has Natasha Vasandani been in? The young actor is making her television debut with Steeltown Murders, but has previously acted in several short films.
Aneurin Barnard plays Joseph Kappen
Who is Joseph Kappen? Joseph is a Port Talbot man suspected of some involvement in the deaths of three local women.
Walter van Dyk plays Mr Croiset
Who is Mr Croiset? Mr Croiset is a Dutch psychic, who is called in by South Wales Police to help with the murder investigation at one particularly desperate moment.
Dyfan Dwyfor plays DS Vic Jenkins
Who is DS Vic Jenkins? Vic was serving as a senior detective on the South Wales Police at the time of the murders.
What else has Dyfan Dwyfor been in? Outlander fans may recognise Dwyfor as Private Hughes in the fantasy period drama, while his other credits include Annika, A Very English Scandal and Hinterland.
Richard Harrington plays Colin Dark
Who is Colin Dark? Colin is a forensic scientist, who is involved in Operation Magnum and keen to see it succeed – noting the need for justice and its pioneering techniques.
Steve Nicolson plays DI Tony Warren
Who is DI Tony Warren? A detective working for South Wales Police in the 1970s, at the time the murders took place. He is keen to close the case, but finds himself following the wrong path.
What else has Steve Nicolson been in? Nicolson previously collaborated with screenwriter Ed Whitmore on ITV thriller Manhunt, while he has also appeared in Strike Back, New Tricks and Homeland.