Mahmood Mattan was hanged for a murder he didn't commit. 70 years on, and his execution continues to reverberate in Cardiff, and beyond. His surviving family still have so many unanswered questions - and one grandchild embarks on a journey to try to find answers. Finally, the police issue an apology for its role in the miscarriage - but will the family ever find peace?

Presenter and Producer: Danielle Fahiya Sound Design: Cathy Robinson Original Music: Rhodri Llewellyn John Executive Producers: Karen Voisey and Andy Maguire Story Consultant: John Norton Production Manager: Andrea Deere

History Consultant: Chris Phillips. Archive: BBC Black Britain; ITV Wales

Mahmood Mattan - Ali Goolyad Laura Mattan - Zoe Davies Scottish newspaper journalist - Ian Dunnett Jnr

Mahmood Mattan was hanged 70 years ago for a murder he did not commit. The aftermath of his execution has run deep through the Mattan family. All three of his sons faced years of prejudice because of what happened to their father: lives changed forever by an injustice committed by the State. And in the end, it was too much for them.

Presenter and Producer: Danielle Fahiya Sound Design: Cathy Robinson Original Music: Rhodri Llewellyn John Executive Producers: Karen Voisey and Andy Maguire Story Consultant: John Norton Production Manager: Andrea Deere

History Consultant: Chris Phillips. Archive: BBC Black Britain; ITV Wales

Laura Mattan; newspaper journalist; Yasmin Fahiya - Zoe Davies Scottish newspaper journalist - Ian Dunnett Jnr Eddie Mattan - Dean Rehman David Mattan - Anthony Corria

Mahmood Mattan's family received a six-figure compensation pay-out after his conviction for murder was quashed - but it didn't bring them the peace of mind they craved. The "blood money" brought with it its own problems, as his sons increasingly struggled to cope. And that was compounded by a police re-investigation which failed to identify any "new lines of enquiry". Lily's killer would never be found.

Presenter and Producer: Danielle Fahiya Sound Design: Cathy Robinson Original Music: Rhodri Llewellyn John Executive Producers: Karen Voisey and Andy Maguire Story Consultant: John Norton Production Manager: Andrea Deere

History Consultant: Chris Phillips. Archive: BBC Black Britain; ITV Wales

Dean Rehman - Eddie & David Mattan Ian Dunnett Jnr - Newspaper reporter and procurator fiscal

Desperate to clear Mahmood Mattan's name, his family have one last throw of the dice. It works - and finally his widow and three sons have their day in court. Forty six years after Mattan was hanged, a series of revelations are made which seriously undermine the case against him. And, explosive new evidence emerges which points the finger at who the real killer could be.

Presenter and Producer: Danielle Fahiya Sound Design: Cathy Robinson Original Music: Rhodri Llewellyn John Executive Producers: Karen Voisey and Andy Maguire Story Consultant: John Norton Production Manager: Andrea Deere

History Consultant: Chris Phillips. Archive: BBC Black Britain; ITV Wales

Zoe Davies - Laura Mattan Dean Rehman - Phillip Mattan; and Eddie Mattan

For years, Mahmood Mattan's family believed in his innocence. But no-one would listen. Then in 1969, a shocking revelation - another vicious attack which bore many of the hallmarks of the murder of Lily Volpert. And the man responsible for that attack was also a vital witness in the case against Mattan. Finally, could the family prove once and for all that Mattan was an innocent man who should never have been sent to the gallows?

Presenter and Producer: Danielle Fahiya Sound Design: Cathy Robinson Original Music: Rhodri Llewellyn John Executive Producers: Karen Voisey and Andy Maguire Story Consultant: John Norton Production Manager: Andrea Deere

History Consultant: Chris Phillips. Archive: BBC Black Britain; ITV Wales

James Callaghan, Edmund Davies & Melbourne Thomas - Richard Elfyn Tom Driberg & Rhys Roberts - Rhys Downing Harold Cover - Anthony Corria Margaret Bush - Zoe Davies David Wickham - Dean Rehman

After Mahmood Mattan was hanged, his wife Laura was left alone to bring up three young children. She had little, or no, support; and moved her family to a new area of Cardiff where she hoped to start a new life. But some people wouldn't let her forget that she had been married to a man convicted and hanged for murder. She faced abuse and was ostracised; her young family suffered the most terrible cruelty and humiliation. But the trauma that she and her three sons endured didn't end there. It continues to be felt even today by the generations of their family that followed.

Presenter and Producer: Danielle Fahiya Sound Design: Cathy Robinson Original Music: Rhodri Llewellyn John Executive Producers: Karen Voisey and Andy Maguire Story Consultant: John Norton Production Manager: Andrea Deere

History Consultant: Chris Phillips. Archive: BBC Black Britain; ITV Wales

Laura Mattan - Zoe Davies Newspaper journalist & Insp Harry Power - Richard Elfyn 2nd newspaper journalist - Dean Rehman

Within six months of his arrest, Mahmood Mattan found himself on trial for murder. But could he ever receive a fair trial? A black man was facing the gallows and he had to place his faith in an all-white jury. There was little forensic evidence against him; and witness testimony which kept changing. And the motivation for the prosecution's star witness has been questioned. Even the actions of his own barrister have been called into doubt.

Presenter and Producer: Danielle Fahiya Sound Design: Cathy Robinson Original Music: Rhodri Llewellyn John Executive Producers: Karen Voisey and Andy Maguire Story Consultant: John Norton Production Manager: Andrea Deere

History Consultant: Chris Phillips. Archive: BBC Black Britain; ITV Wales

Edmund Davies, Justice Ormerod & newspaper journalist - Richard Elfyn Court clerk, Doris and Elizabeth Williams - Zoe Davies TE Rhys-Roberts & police officer - Rhys Downing Mahmood Mattan - Ali Goolyad Harold Cover - Anthony Corria

Aged just 10, Ruth was just yards away when her aunty was brutally murdered. For the first time, Ruth tells publicly the story of how Lily Volpert was killed in the shop she owned, and they lived in as a family. The police in Cardiff were struggling to make any progress as they hunted for "the silent killer". Then a reward brought forward key witnesses. Despite inconsistencies in testimony, the police made their move and arrested a Somali seaman, Mahmood Mattan.

Presenter and Producer: Danielle Fahiya Sound Design: Cathy Robinson Original Music: Rhodri Llewellyn John Executive Producers: Karen Voisey and Andy Maguire Story Consultant: John Norton Production Manager: Andrea Deere

History consultant: Chris Phillips Archive: BBC Black Britain; ITV Wales.

Police officer and journalist - Richard Elfyn Mahmood Mattan - Ali Goolyad Doris, Margaret Bush & Mary Tolley - Zoe Davies Police officer, Echo vendor and TE Rhys-Roberts - Rhys Downing Harold Cover - Anthony Corria Journalist - Ian Dunnett Jnr

Mahmood Mattan came to the UK from Somalia to seek a better life. He met and fell in love with a local woman from Cardiff. But in the 1950s, their mixed marriage was frowned upon. And that racial hostility simmered away in Mahmood's life, and probably played a part in his death. He was arrested, convicted and hanged for the murder of shopkeeper Lily Volpert. His execution took place 70 years ago - and it would take decades for his name to be cleared. And even today, the repercussions of that miscarriage of justice are still being felt.

Presenter and Producer: Danielle Fahiya Sound Design: Cathy Robinson Original Music: Rhodri Llewellyn John Executive Producers: Karen Voisey and Andy Maguire Story Consultant: John Norton Production Manager: Andrea Deere

History consultant: Chris Phillips Newspaper reporter: Ian Dunnett Jnr Archive: BBC Black Britain; ITV Wales.

Somali seaman Mahmood Mattan was hanged for a crime he didn't commit. On March 6th, 1952, Lily Volpert was murdered in the shop she ran in Cardiff's Tiger Bay. What followed was a flawed police investigation and prejudiced trial that ultimately led to Mahmood being hanged for a crime he was not responsible for. After 46 years, his innocence was finally proved in a court of law. But the impact of Lily's murder and Mahmood's execution are still being felt by two families today. For the first time, we hear from the family of murder victim Lily. Ruth was just yards away when her aunty was murdered, and she still doesn't know who killed her. And the surviving family members of Mahmood's family open up about the trauma they felt - and continue to feel to this day - 70 years after Mahmood was hanged.