It was 19 January 1944 and although there were still the occasional sounds of German bombers in the skies above Portsmouth, compared with the saturation raids of 1940 and 1941, the city was a much quieter place - if any city filled with tens of thousands of sailors, soldiers and airmen can ever be described as “quiet”.

Beyond Portsmouth - beyond Britain, in fact - the tide of war had finally turned in favour of the Allies, once and for all and everyone knew that an invasion of occupied Europe was only a matter of time.

The build-up of American troops in particular made it obvious that the killer strike against the Nazis would come later that year, opening the major front in the west, as Russian forces began pressing from the east and British, American and Commonwealth troops pushed up the length of Italy.

Everyday conditions were still harsh - rationing was getting stricter by the day and thousands were housed in temporary shelters, thanks to Herr Goering’s urban demolition scheme, but despite this, there was a “feel good” factor beginning to grow among the population.

It had already been a long war and nobody expected it to end suddenly, but there was now a definite light at the end of what had been a very black and hazardous tunnel and the once all-conquering forces of Hitler now looked anything but unbeatable.

Maybe not tomorrow, maybe not next week, nor even next month, but the war was definitely heading towards an end - and victory.

However, for one woman in particular, her troubles were only just about to begin ...

That evening, a handful of people were gathered together in a small flat above a chemist’s shop at 301 Copnor Road, the heavy blackout curtains drawn and the room lit only by a dim red lamp.

Helen Duncan, a 47-year-old mother of six from Scotland was the reason for this small gathering, for she was a noted medium and this was a seance, during which she would attempt, through her “spirit guide”, Albert Stewart, to contact the deceased loved ones of the other people in the room with her.

However, as Helen seemed to have slipped into a trance and what appeared to be white ectoplasm appeared from her mouth, one of the “sitters” stood up, took out a police whistle and blew several loud blasts on it.

At his signal, the flat was suddenly filled with uniformed police officers, whilst the plain clothes officer who had given it made a futile grab for what he believed to be a sheet of white muslin.

For some minutes, the room was a scene of total confusion, as officers handcuffed and searched everyone, then all but tore the place apart in their attempts to discover sheets, fake beards, or any other evidence of trickery.

But this time, although Helen Duncan had been convicted of fraud more than a decade earlier, they found nothing at all.

That, you might think, should have been that, but instead, Mrs Duncan and three of her sitters were whisked off to the police station for questioning, before charges were laid against the medium before Portsmouth Magistrates Court the next day.

The actual charge specified that day was one of vagrancy, even though Helen had lived in Portsmouth for most of the previous five... years, but this.. was only a... “holding”... charge and much worse was to come.

Even had she been found guilty of this ridiculous charge, by the standards of the day, Helen would normally only have expected to receive a fine of five shillings.

But instead of this, her case was remanded, she was refused bail and sent to Holloway Prison in London, pending further investigations and possible additional charges.

And further charges soon came - first the vagrancy charge was changed to one of conspiracy and this was a serious development, for in wartime Britain, this carried a maximum penalty of death by hanging.

Then, by the time the case had been transferred to the Old Bailey, an extra charge was added, under a law that was already more than two centuries old, evethen - the 1735 Witchcraft Act.

The case immediately hit the headlines up and down the country and a fund was quickly established to help pay for Helen’s defence, but the trial, when it finally began, was a farce from start to finish, for the authorities were determined that she would be found guilty and locked away for at least six months.

And, when the guilty verdict was duly returned, that’s exactly what happened and, unusually, Helen Duncan served every day of the six month sentence, without a single day of remission.

And this, even though she was a model prisoner and such was the sympathy among her jailers that it was said that her cell was not once locked, neither day nor night, throughout her stay in Holloway.

After the guilty verdict was announced - the judge declared that Helen was guilty of dishonesty, although the jury said that she was actually guilty of practices that contravened the 1735 legislation - Portsmouth’s Chief of Police was called to give evidence as to her background.

He told the court that she was married to a cabinet maker and had six children, aged from eighteen to 26 and that she had been visiting Portsmouth for about five years.

He then went on to describe Helen as “an unmitigated humbug and pest” and added that she had previously been guilty of revealing the loss of one of His Majesty’s ships ... That much, at least, was true, but as to the rest of it ...

It was, of course, a complete “fit up”, sanctioned from on high, although not, as things transpired, by Prime Minister Churchill, who was outraged at what he described as a “total waste of the he described as a “total waste of the public resources”.

Unfortunately, even Churchill was powerless to intervene in Helen’s plight, although his curt note to the Home Secretary read: "Give me a report of the 1735 Witchcraft Act . What was the cost of a trial to the State in which the Recorder ( junior magistrate) was kept busy with all this obsolete tomfoolery to the detriment of the necessary work in the courts?"

The press dubbed Helen “Hellish Nell”, but even their hearts weren’t really in any campaign against her and the public at large, as well as several leading legal experts, were largely sympathetic to her plight - though to no avail.

The reason for her harsh treatment and the “witch hunt” which led to her imprisonment can be traced back to a seance nearly four years earlier.

At that “sitting”, the figure of a dead sailor materialised, dressed in full uniform, with the name HMS Barham on his cap band. He conversed with Helen, revealing that the battleship had been sunk in the Mediterranean a few days earlier and somehow this news was leaked to the press.

The government and military authorities were furious, as they had been desperately trying to hush up the loss of such a major ship - in 1941 the war had been going badly for Britain and only the perceived might and infallibility of the Royal Navy gave those back on the home front any cause for real hope.

By early 1944, Helen’s “fame” had spread considerably and the fact that she was now basing most of her activities in Portsmouth, the spiritual heart of the Royal Navy, was a cause of great concern to the authorities.

Everyone - on both sides of the Channel - may well have known that an invasion was coming, but nobody, outside the highest inner circle, could be really sure exactly when and where the first landings would eventually take place.

So, despite the fact that the lawyers were determined to debunk Helen’s psychic abilities, there were clearly those who lived in daily fear that somehow she might hit upon the details of Operation Overlord and that they would then also be leaked.

Ridiculous though it might now sound to us, it was a real fear and the secret service was determined to find some way - any way - to put a stop to her activities, at least until the invasion had taken place.

We might ask ourselves whether or not it might have been simpler - and probably less expensive - for someone to have had a quiet word with Helen and offer her a temporary “pension” of say ten pounds per week for a year, on condition that she “retired” to somewhere obscure for a time.

Instead, a giant hammer was used to crack what was probably only a very small nut and, despite the testimonies of several credible and some fairly eminent witnesses on her behalf, Helen Duncan felt the full weight of the law fall on her from a very great height.

After her release, Helen indeed returned to her career as a medium - although whether “medium” is actually a good term to describe someone who tipped the scales at close to 22 stones is open to debate - but that wasn’t the end of her persecution.

Despite the lack of any official complaints against her and even the fact that Winston Churchill was both a sympathiser - and, allegedly a one-time client - the police continued to monitor most of what she did.

Any chance of a further prosecution under the archaic Witchcraft Act had been removed in 1951, when Churchill returned to power and backed a private member’s bill to squash that ridiculous piece of legislation, once and for all.

Three years later, a formal Act of Parliament recognised spiritualism as a religion.

The police, however, were convinced that Helen Duncan was a fraud and determined, because of the continuing swell of public sympathy against what had been done to her earlier, to find evidence to bring a charge that would stick in a properly conducted trial.

Finally, in November 1956, they must have thought that they had her, bursting into a seance in a Nottingham house.

Despite protests from others present that a medium in a trance should never be physically touched, because the ectoplasm would return to the body far too quickly, officers grabbed the poor woman and tried to haul her off.

Helen, however, collapsed and a doctor had to be summoned - a doctor whose physical examination revealed two second degree burns across her stomach.

It was soon apparent that Helen was really ill - so ill, that she was rushed back to her home in Scotland and later to a nearby hospital.

Five weeks after that final police raid, Helen Duncan was dead.

Much has been written about Helen Duncan and there are several books and websites dedicated to her story, as well as a campaign and petition demanding that the Home Secretary should issue a posthumous pardon for that crazy 1944 conviction.

However, one thing does occur to me, which no one else, either in 1944 or since, appears to have considered.

The dead sailor who appeared at Helen’s seance in 1941 had HMS Barham on his cap, yet, during the years of the war, sailors and officers of the Royal Navy wore cap and hat bands that said only HM Ships, as a security measure against potential spies in the community.

It would be interesting to know if anyone can come up with a possible explanation for that one ...