The Pembrokeshire Murders

● The Pembrokeshire Murders is a three-part true crime documentary series.

● The documentary examines the investigation into the murders of Richard and Helen Thomas in 1985 and Peter and Gwenda Dixon in 1989.

● John Cooper was convicted of all four murders in 2011 following a major cold-case investigation.

● The series follows journalist Andy Chandler and legal assistant Hayley Wood as they examine material connected to the case.

● The documentary explores competing interpretations of the evidence and the questions raised by later investigations.

● The Pembrokeshire Murders is coming to Sky Documentaries and NOW in 2026.

In 1985, the Welsh county of Pembrokeshire was shaken by the murders of siblings Richard and Helen Thomas. Four years later, married couple Peter and Gwenda Dixon were found shot dead on the Pembrokeshire Coast Path during a holiday in the area.

The investigations remained unsolved for many years before local resident John Cooper was convicted of all four murders in 2011 following a landmark cold-case inquiry that attracted national attention.

The case later became the subject of a television drama, renewing public interest and prompting fresh discussion among some members of the local community.

The Pembrokeshire Murders follows journalist Andy Chandler and legal assistant Hayley Wood as they independently examine material connected to the case. As their research develops, the pair join forces to investigate questions surrounding the original conviction, the evidence presented and other information that has emerged over time.

Produced by Magna Studios, the series combines first-hand testimony, previously unseen material and expert analysis to explore multiple perspectives on a case that continues to generate debate.

The documentary examines evidence raised by Chandler and Wood, alongside the views of investigators involved in the original case, who remain confident that justice was served and that the correct conclusions were reached.

As the Criminal Cases Review Commission reviews material related to the case, the series explores different explanations for what has been uncovered and considers the arguments both supporting and challenging Cooper's conviction.

At the heart of the documentary is a question about certainty, evidence and what happens when new information emerges about a case that many believed had already been settled.

Yes. The documentary examines the real murders of Richard and Helen Thomas in 1985 and Peter and Gwenda Dixon in 1989.

John Cooper was convicted of the four murders in 2011 following a cold-case police investigation. The series explores questions raised by material connected to the case and examines differing views around the evidence involved.

The documentary centres on Andy Chandler and Hayley Wood, two Pembrokeshire residents whose independent investigations brought them together to explore the case in greater depth.

Viewers also hear from contributors connected to the investigation, alongside experts, witnesses and individuals with direct knowledge of events surrounding the case.

Andy Chandler is a journalist who was working at The Pembrokeshire Herald when he began researching the murders.

Hayley Wood is a legal assistant and miscarriage of justice advocate based in Pembroke Dock.

The series explores questions raised by material reviewed by Chandler and Wood during their investigation.

Their findings prompted further discussion about aspects of the original case and contributed to renewed interest in the evidence. The documentary presents a range of perspectives and examines the arguments made by different parties.

The Pembrokeshire Murders is a three-part documentary series.

The Pembrokeshire Murders launches on Sky Documentaries in 2026.

The series will also be available to stream on NOW.