In the bedroom, with a carving-knife

Early on the morning of 6 May 1840, a young housemaid in a respectable Mayfair street discovered that her master, the elderly and mildly eccentric peer Lord William Russell, had been murdered in his bed. His throat had been hacked at like a joint of meat, slicing through the windpipe and almost severing his head. It turned out not to be much of a whodunit. Within a few days, a young Swiss-born valet in the house named François Courvoisier was taken away for questioning, and faced by a pile of circumstantial evidence eventually he confessed to the crime. The real question is why he did it.

The answer that shocked everyone at the time was that he was following the lead of Jack Sheppard, the thief and prison-breaker who had recently featured as the hero of a wildly successful novel by William Harrison Ainsworth, and then had become a cult hero with working-class audiences who flocked to see theatrical adaptations of the story.