A bitterly cold, dark January night. A store manager, weary from a day and half a night of year-end stocktaking, locks the door of his shop and trudges off home in the swirling mist. He takes a short cut through a yard near the shop when, in front of him, he sees the outline of two bare legs.

This was the opening scene of the murder of Margaret Schofield, a Dewsbury prostitute, discovered on the night of Friday, January 2nd, 1931, by John Sprentall, the store manager. She was naked from the waist down and part of her upper clothing was missing.

There were more red herrings to this case than there are in the sea. A bloodstained beer bottle lying near the body wasn’t the murder weapon, nor was the bar of a pram axle close to it. There were two “confessions,” one by a destitute cobbler and the other by a deranged fellow, neither of who was the murderer.

Margaret had been beaten repeatedly on the head. None of the blows was delivered by anyone of any real strength. The killer took her distinctive, very fashionable fur-trimmed coat and threw it into the River Calder a few hundred yards away. So could it have been a woman?