Based on the adventures of Jack Sheppard, the thief and jail-breaker who became a folk hero in 1720s London. Jack is working as an apprentice to a clockmaker when his brother Tom is sentenced to be hanged for theft. To save Tom (who has a wife and children) he goes for help to the brutal 'Thief-taker General' Jonathan Wild. Wild mediates between the government and the criminal underworld, fencing stolen goods and delivering thieves who don't pay him tribute over to the authorities. He assigns Jack a robbery in return for saving Tom from the gallows, but when Jack learns that Tom is instead to be 'transported' to the colonies for a life of hard labour he refuses to cut Wild in on the proceeds. An angry Wild has Jack thrown in Newgate prison, from which he escapes, forming his own criminal outfit with another of Wild's disgruntled associates, Joseph 'Blueskin' Blake. Determined to crush this affront to his authority, Wild uses Jack's mistress Bess to trap him and has him jailed again.