Sixty-five years after a female body was found hidden under leaves in a corner of a cemetery in Hampstead, London, police are still hopeful of solving the mystery surrounding the death of the woman – the estranged wife of a civil servant from Pembroke Dock.

Called by the press 'The Skeleton in the Cemetery Mystery', the discovery of the remains of 49-year-old Marion Gwendolen Duignan made headlines in 1956, and is still a talking point in the Hampstead area to this day.

It was on Saturday February 25, 1956 that a gravedigger discovered a decomposed body under a holly bush in a remote part of historic Hampstead Cemetery. He called the police and a murder investigation was launched.

The remains were those of a woman about 5ft 2in tall, wearing a blue and white check three-quarter length coat, a black skirt, and a blue blouse. Medical evidence suggested that the woman had died over a year earlier. The police concluded that she had been murdered and that the killer had brought the body to hide in a shallow grave, but had panicked and left it covered with leaves, under the bush.

The first task was to identify the body. Because the victim's teeth had been well looked after, the police issued photographs and a chart to all London dentists, one of whom came back with the information that the body was that of Marion Duignan of 23 Tanza Road, Hampstead. She had been reported missing in August 1953 and soon the police were interviewing her husband, a civil servant named Frederick William Duignan.

Frederick Duignan was born in 1894 to Thomas Charles Duignan, a Staff Quartermaster Sergeant in the Army Service Corps, stationed in Pembroke Dock, and his wife Agnes Maria, daughter of Thomas Page who kept the White Hart pub in Pembroke Street. At the time of Frederick's birth they lived at 4 Gwyther Street.

Thomas was posted to Preston soon afterwards, where he died the following year at the age of 35. His widow remarried a few years later and moved to Woolwich, leaving Frederick to lodge with his grandparents. He attended Pembroke Dock County School and by 1911 he was a solicitor's clerk, later working in the Tax Office in Haverfordwest.

After serving in the Royal Welsh Fusiliers during the First World War, Frederick resumed his former career and moved to Hendon in Middlesex to work as a tax inspector. When the police interviewed him he told them he had met Marion Gwendoline Beust-Dixon at a party at a friend’s house in Hendon. She was a very attractive woman who worked as a secretary at her father’s company in the City.

They were married in 1931 and spent their honeymoon in Pembrokeshire. Later they moved to Tanza Road in Hampstead and had two children, Theodora and Anthony, who joined the Merchant Navy.

The marriage was initially happy. However, as Frederick explained in an interview: ‘The last 15 years of our marriage was really a polite estrangement. I lived my life, she lived hers. We had separate rooms and all we shared were the larder and the roof. My wife went out quite a bit, but I was more or less a homebird. It was clear we were drifting slowly apart.’

Eventually Frederick left the house in Tanza Road and moved a short distance to 6 Rosslyn Hill where he lived with Phyllis Cowle. They were married in 1956, by which time the couple had moved to Kenton, Middlesex.

In August 1953, a year after Frederick had moved out, Marion vanished. Her daughter Theodora said that she did not have a close relationship with her mother. ‘To me she was always odd. She lived a life of her own, apart from the family. If I showed any interest it was never reciprocated.’

What became of Marion in the two and a half years before her body turned up in Hampstead Cemetery remains a mystery. The police investigation uncovered the information that Marion was a keen spiritualist and also that she occasionally sat as a model for a local artist - none of which was known to the rest of her family – but this failed to shed any light on the mystery.

The body was examined by Dr. Francis Camps the Home Office pathologist, who found no traces of poison, which ruled out suicide from an overdose. At the inquest, the St Pancras coroner decided on an open verdict as it was impossible to determine the cause of death. He praised the pathologist, the dentist and the police, saying that the body had only been identified because of advances in anatomy and dentistry.

Frederick Duignan died from a heart condition in March 1957, just over a year after Marion’s body was discovered.

In November 2015 the Hampstead newspaper Camden New Journal used a Freedom of Information request to try to see the records of the Marion Duignan investigation, but was told the file remained closed until 2025. Reported the newspaper: 'Scotland Yard has ruled the files surrounding the disappearance and death of Marion Duignan must stay locked in the national archives for at least another ten years.

'Historic case files from that era are normally made available for public view at the public records office in Kew, but when the New Journal asked to look at the papers relating to Mrs Duignan, to see what went wrong in the investigation, we were told our request failed a “public interest” test.

'The official reply said: “Primarily, this record relates to the investigation of a suspicious death that was ultimately considered a case of murder that remains unsolved. Essentially this murder could still achieve prosecution”.'