When three boys discovered the skeletal remains of a woman stuffed feet first into a hollow tree on Sunday, April 18th, 1943, a mystery was set in motion that led right up to Rudolph Hess, Hitler’s deputy.

The tree, a wych elm, was in Hagley Wood, half-way between Stourbridge and Birmingham. The skeleton was concealed in a small hole only 24 inches in diameter and three and a half feet from the ground.

From the limited remains forensic scientists gradually built up a picture of the woman. She was only five feet tall, aged between 25 and 40, with mousey brown hair and irregular teeth in her lower jaw. Her body had probably been pushed into the tree cavity 18 months before it was found.

The case might have died there for lack of progress, buried under wartime news. But someone was determined it should not die. All around the West Midlands chalk messages began to appear in public places: WHO PUT BELLA DOWN THE WYCH ELM – HAGLEY WOOD?

Why Bella? Theories began to mushroom. Bella, it was pointed out, was a witch’s name, and wych elms are associated with witches. If she wasn’t a witch she was a German spy (or both); if not, a prostitute killed by her pimp, or she was perhaps the unwanted wife of an American serviceman.

Then a woman wrote to the local newspaper under a nom-de-plume claiming that “the person responsible for the crime died insane in 1942, and the victim was Dutch and arrived illegally in England in about 1941.”

The letter-writer was traced by police and the story emerged that some Nazi leaders were strongly influenced by astrologers, including Hitler himself. Deputy Fuhrer Rudolph Hess flew to Britain in May, 1941, on an abortive peace mission – having, it is said, received advice from astrologers.

The Dutch connection came about because Holland was the main centre used by the Germans to infiltrate spies into Britain. One prominent Dutch agent acting for the Germans, a man named Lehrer, had a Dutch mistress who knew Britain well enough to pass as a native. She had had a pre-war love affair with a man who lived in Stourbridge – only five miles from Hagley Wood.

In March and April, 1941, five agents were infiltrated into England from Holland. Two landed by parachute and were captured. Two came by boat and one, a woman using the code-name Clara, arrived in the area between Kidderminster and Birmingham.

Was Clara the Bella of the graffiti, and was she the same woman as Lehrer’s Dutch mistress? The author Donald McCormick, researching the case, discovered an ex-Nazi who knew Lehrer’s ex-mistress. He could not remember her name but she was, he said, about 30, well below average height, and her teeth were irregular. She was certainly a German spy and she had an ex-lover living in Stourbridge.

Clara also dabbled in fortune-telling and, it is thought, she could have been one of the astrologers active in Germany whose advice prompted Hess’s ill-fated flight. The astrology connection thus provides the link with Bella, witchcraft and espionage. But how this German woman spy came to end up in the wych elm – if indeed this was her – and who the graffiti writer was, are things we shall never know.