Dr. Hawley Harvey Crippen was a mild-mannered, henpecked little American whose domineering wife Cora vanished in January 1910. She had returned to the United States because of a relative’s illness, he told inquirers. At the same time he moved his secretary and mistress Ethel le Neve into his Hilldrop Crescent home in Camden, and she was soon seen wearing his wife’s furs and jewellery.

Cora’s friends reported her disappearance to Scotland Yard, and Detective Chief Inspector Walter Dew searched the house, finding nothing of significance. But the search alarmed Crippen, who fled with his mistress to Antwerp, where they boarded the SS Montrose, bound for Canada.

The pair’s disappearance prompted a more thorough search of 39 Hilldrop Crescent, and dismembered human remains were found buried in the cellar. The presence of the poison hyoscine was detected, and a fragment of abdominal scar tissue identified the remains as Cora’s.

Meanwhile Crippen was crossing the Atlantic, with Ethel disguised as a boy to prevent identification. But the couple’s affectionate behaviour made the ship’s captain suspicious. He radioed London, and Dew boarded a faster liner, to confront the two fugitives on their arrival in Canada. Their subsequent arrest made history – it was the first time wireless had been used in a murder hunt.

Crippen was convicted of his wife’s murder and sentenced to death. Ethel le Neve was tried separately, and was acquitted of being an accessory after the fact.

Crippen’s executioner John Ellis later recorded: “As I opened the peephole in his cell door and looked on the man who had set the whole world by the ears, I marvelled at his complete calmness. He sat at a table writing, and would occasionally break off to chat pleasantly and in a most affable way to the two warders in there with him.

“Most people had by now come to think of Crippen as a monster in human guise, but I’ll say this for him, that even in the hideous clothes of a convict he had a natural amiability and innate gentlemanliness that endeared him even to his warders. I speak of men as I find them, and Crippen came across to me as a most pleasant fellow.”

Even so, later that night Crippen tried to outwit his warders and cheat justice. He secretly broke his glasses, hiding the fragments with the intention of using them to cut his throat, but the warders became suspicious and the broken spectacles were discovered.

At his execution the next day, NOVEMBER 23rd, 1910, Crippen’s warders looked far more distressed than the 48-year-old condemned doctor, Ellis recalled. “I could see him smiling as he approached, and the smile never left his face up to the moment when I threw the white cap over it and blotted out God’s light from his eyes for ever.”