A skeleton on display in a London medical museum belongs to the man who ran the city’s underworld while the public thanked him for fighting crime. Jonathan Wild was born poor in Wolverhampton in the early 1680s and came to a London of around 600,000 people with no police force, only unpaid parish constables. Thrown into the Wood Street Compter for debt in 1710, he learned how corruption worked by running errands for the jailers and lending to inmates, and a prostitute named Mary Milliner taught him the stolen goods trade. He then studied extortion as assistant to the crooked under-marshal Charles Hitchen and took the racket from him.

This episode explains the closed loop Wild built from an office in the Old Bailey. His gang stole the goods, victims paid him a finder’s fee to recover them, and any thief who held out was handed to the hangman for the government’s 40 pound bounty. The scheme lasted until Wild met Jack Sheppard, a burglar who refused to work for him and kept escaping from prison. The feud turned London against the self-appointed Thief-Taker General, his own men testified, and he was hanged at Tyburn before a jeering crowd.

• When Hitchen tried to expose him in print, Wild answered with a pamphlet revealing Hitchen’s visits to molly houses, which ended him as a threat.
• In 1720 the Privy Council asked Wild for advice on crime, and he persuaded them to raise the bounty for thieves from 40 pounds to 140.
• He advertised a lost notebook found near a tavern known as a brothel, a public hint to its owner to pay up or be exposed.
• Blueskin Blake, denied Wild’s help at his trial, slashed Wild’s throat with a pocket knife in open court.
• Convicted in 1725 over 50 yards of stolen lace, Wild tried laudanum on the morning of his execution, and Arthur Conan Doyle later cited him as the model for Professor Moriarty.